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* Re: [PATCH v2 16/17] memblock: implement for_each_reserved_mem_region() using __next_mem_region()
From: Baoquan He @ 2020-08-05  9:11 UTC (permalink / raw)
  To: Mike Rapoport
  Cc: Emil Renner Berthing, linux-sh, Peter Zijlstra, Dave Hansen,
	linux-mips, Max Filippov, Paul Mackerras, sparclinux, linux-riscv,
	Will Deacon, Stafford Horne, Marek Szyprowski, linux-arch,
	linux-s390, linux-c6x-dev, Yoshinori Sato, x86, Russell King,
	Mike Rapoport, clang-built-linux, Ingo Molnar, linux-arm-kernel,
	Catalin Marinas, uclinux-h8-devel, linux-xtensa, openrisc,
	Borislav Petkov, Andy Lutomirski, Paul Walmsley, Thomas Gleixner,
	Hari Bathini, Michal Simek, linux-mm, linuxppc-dev, linux-kernel,
	iommu, Palmer Dabbelt, Andrew Morton, Christoph Hellwig
In-Reply-To: <20200802163601.8189-17-rppt@kernel.org>

On 08/02/20 at 07:36pm, Mike Rapoport wrote:
> From: Mike Rapoport <rppt@linux.ibm.com>
> 
> Iteration over memblock.reserved with for_each_reserved_mem_region() used
> __next_reserved_mem_region() that implemented a subset of
> __next_mem_region().
> 
> Use __for_each_mem_range() and, essentially, __next_mem_region() with
> appropriate parameters to reduce code duplication.
> 
> While on it, rename for_each_reserved_mem_region() to
> for_each_reserved_mem_range() for consistency.
> 
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> ---
>  .clang-format                    |  2 +-
>  arch/arm64/kernel/setup.c        |  2 +-
>  drivers/irqchip/irq-gic-v3-its.c |  2 +-
>  include/linux/memblock.h         | 12 +++------
>  mm/memblock.c                    | 46 +++++++-------------------------
>  5 files changed, 17 insertions(+), 47 deletions(-)

Reviewed-by: Baoquan He <bhe@redhat.com>


^ permalink raw reply

* Re: [PATCH v2 15/17] memblock: remove unused memblock_mem_size()
From: Baoquan He @ 2020-08-05  8:29 UTC (permalink / raw)
  To: Mike Rapoport
  Cc: Emil Renner Berthing, linux-sh, Peter Zijlstra, Dave Hansen,
	linux-mips, Max Filippov, Paul Mackerras, sparclinux, linux-riscv,
	Will Deacon, Stafford Horne, Marek Szyprowski, linux-arch,
	linux-s390, linux-c6x-dev, Yoshinori Sato, x86, Russell King,
	Mike Rapoport, clang-built-linux, Ingo Molnar, linux-arm-kernel,
	Catalin Marinas, uclinux-h8-devel, linux-xtensa, openrisc,
	Borislav Petkov, Andy Lutomirski, Paul Walmsley, Thomas Gleixner,
	Hari Bathini, Michal Simek, linux-mm, linuxppc-dev, linux-kernel,
	iommu, Palmer Dabbelt, Andrew Morton, Christoph Hellwig
In-Reply-To: <20200802163601.8189-16-rppt@kernel.org>

On 08/02/20 at 07:35pm, Mike Rapoport wrote:
> From: Mike Rapoport <rppt@linux.ibm.com>
> 
> The only user of memblock_mem_size() was x86 setup code, it is gone now and
> memblock_mem_size() funciton can be removed.
> 
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> ---
>  include/linux/memblock.h |  1 -
>  mm/memblock.c            | 15 ---------------
>  2 files changed, 16 deletions(-)
> 
> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> index d70c2835e913..ec2fd8f32a19 100644
> --- a/include/linux/memblock.h
> +++ b/include/linux/memblock.h
> @@ -450,7 +450,6 @@ static inline bool memblock_bottom_up(void)
>  
>  phys_addr_t memblock_phys_mem_size(void);
>  phys_addr_t memblock_reserved_size(void);
> -phys_addr_t memblock_mem_size(unsigned long limit_pfn);
>  phys_addr_t memblock_start_of_DRAM(void);
>  phys_addr_t memblock_end_of_DRAM(void);
>  void memblock_enforce_memory_limit(phys_addr_t memory_limit);
> diff --git a/mm/memblock.c b/mm/memblock.c
> index c1a4c8798973..48d614352b25 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1656,21 +1656,6 @@ phys_addr_t __init_memblock memblock_reserved_size(void)
>  	return memblock.reserved.total_size;
>  }
>  
> -phys_addr_t __init memblock_mem_size(unsigned long limit_pfn)
> -{
> -	unsigned long pages = 0;
> -	unsigned long start_pfn, end_pfn;
> -	int i;
> -
> -	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
> -		start_pfn = min_t(unsigned long, start_pfn, limit_pfn);
> -		end_pfn = min_t(unsigned long, end_pfn, limit_pfn);
> -		pages += end_pfn - start_pfn;
> -	}
> -
> -	return PFN_PHYS(pages);
> -}

Reviewed-by: Baoquan He <bhe@redhat.com>


^ permalink raw reply

* [PATCH v10 2/5] powerpc/vdso: Prepare for switching VDSO to generic C implementation.
From: Christophe Leroy @ 2020-08-05  7:09 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl,
	anton
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev
In-Reply-To: <cover.1596611196.git.christophe.leroy@csgroup.eu>

Prepare for switching VDSO to generic C implementation in following
patch. Here, we:
- Prepare the helpers to call the C VDSO functions
- Prepare the required callbacks for the C VDSO functions
- Prepare the clocksource.h files to define VDSO_ARCH_CLOCKMODES
- Add the C trampolines to the generic C VDSO functions

powerpc is a bit special for VDSO as well as system calls in the
way that it requires setting CR SO bit which cannot be done in C.
Therefore, entry/exit needs to be performed in ASM.

Implementing __arch_get_vdso_data() would clobber the link register,
requiring the caller to save it. As the ASM calling function already
has to set a stack frame and saves the link register before calling
the C vdso function, retriving the vdso data pointer there is lighter.

Implement __arch_vdso_capable() and:
- When the timebase is used, make it always return true.
- When the RTC clock is used, make it always return false.

Provide vdso_shift_ns(), as the generic x >> s gives the following
bad result:

  18:	35 25 ff e0 	addic.  r9,r5,-32
  1c:	41 80 00 10 	blt     2c <shift+0x14>
  20:	7c 64 4c 30 	srw     r4,r3,r9
  24:	38 60 00 00 	li      r3,0
...
  2c:	54 69 08 3c 	rlwinm  r9,r3,1,0,30
  30:	21 45 00 1f 	subfic  r10,r5,31
  34:	7c 84 2c 30 	srw     r4,r4,r5
  38:	7d 29 50 30 	slw     r9,r9,r10
  3c:	7c 63 2c 30 	srw     r3,r3,r5
  40:	7d 24 23 78 	or      r4,r9,r4

In our case the shift is always <= 32. In addition,  the upper 32 bits
of the result are likely nul. Lets GCC know it, it also optimises the
following calculations.

With the patch, we get:
   0:	21 25 00 20 	subfic  r9,r5,32
   4:	7c 69 48 30 	slw     r9,r3,r9
   8:	7c 84 2c 30 	srw     r4,r4,r5
   c:	7d 24 23 78 	or      r4,r9,r4
  10:	7c 63 2c 30 	srw     r3,r3,r5

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v10:
- Added a comment to explain the reason for the two stack frames.
- Moved back the .cfi_register next to mflr

v9:
- No more modification of __get_datapage(). Offset is added after.
- Adding a second stack frame because the PPC VDSO ABI doesn't force
the caller to set one.

v8:
- New, splitted out of last patch of the series
---
 arch/powerpc/include/asm/clocksource.h       |   7 +
 arch/powerpc/include/asm/vdso/clocksource.h  |   7 +
 arch/powerpc/include/asm/vdso/gettimeofday.h | 185 +++++++++++++++++++
 arch/powerpc/kernel/vdso32/vgettimeofday.c   |  29 +++
 arch/powerpc/kernel/vdso64/vgettimeofday.c   |  29 +++
 5 files changed, 257 insertions(+)
 create mode 100644 arch/powerpc/include/asm/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/gettimeofday.h
 create mode 100644 arch/powerpc/kernel/vdso32/vgettimeofday.c
 create mode 100644 arch/powerpc/kernel/vdso64/vgettimeofday.c

diff --git a/arch/powerpc/include/asm/clocksource.h b/arch/powerpc/include/asm/clocksource.h
new file mode 100644
index 000000000000..482185566b0c
--- /dev/null
+++ b/arch/powerpc/include/asm/clocksource.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_CLOCKSOURCE_H
+#define _ASM_CLOCKSOURCE_H
+
+#include <asm/vdso/clocksource.h>
+
+#endif
diff --git a/arch/powerpc/include/asm/vdso/clocksource.h b/arch/powerpc/include/asm/vdso/clocksource.h
new file mode 100644
index 000000000000..ec5d672d2569
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/clocksource.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_VDSOCLOCKSOURCE_H
+#define __ASM_VDSOCLOCKSOURCE_H
+
+#define VDSO_ARCH_CLOCKMODES	VDSO_CLOCKMODE_ARCHTIMER
+
+#endif
diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
new file mode 100644
index 000000000000..e2c462796a22
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
@@ -0,0 +1,185 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_VDSO_GETTIMEOFDAY_H
+#define __ASM_VDSO_GETTIMEOFDAY_H
+
+#include <asm/ptrace.h>
+
+#ifdef __ASSEMBLY__
+
+/*
+ * The macros sets two stack frames, one for the caller and one for the callee
+ * because there are no requirement for the caller to set a stack frame when
+ * calling VDSO so it may have omitted to set one, especially on PPC64
+ */
+
+.macro cvdso_call funct
+  .cfi_startproc
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+	mflr		r0
+  .cfi_register lr, r0
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	get_datapage	r5, r0
+	addi		r5, r5, VDSO_DATA_OFFSET
+	bl		\funct
+	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	cmpwi		r3, 0
+	mtlr		r0
+  .cfi_restore lr
+	addi		r1, r1, 2 * STACK_FRAME_OVERHEAD
+	crclr		so
+	beqlr+
+	crset		so
+	neg		r3, r3
+	blr
+  .cfi_endproc
+.endm
+
+.macro cvdso_call_time funct
+  .cfi_startproc
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+	mflr		r0
+  .cfi_register lr, r0
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	get_datapage	r4, r0
+	addi		r4, r4, VDSO_DATA_OFFSET
+	bl		\funct
+	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	crclr		so
+	mtlr		r0
+  .cfi_restore lr
+	addi		r1, r1, 2 * STACK_FRAME_OVERHEAD
+	blr
+  .cfi_endproc
+.endm
+
+#else
+
+#include <asm/time.h>
+#include <asm/unistd.h>
+#include <uapi/linux/time.h>
+
+#define VDSO_HAS_CLOCK_GETRES		1
+
+#define VDSO_HAS_TIME			1
+
+static __always_inline int do_syscall_2(const unsigned long _r0, const unsigned long _r3,
+					const unsigned long _r4)
+{
+	register long r0 asm("r0") = _r0;
+	register unsigned long r3 asm("r3") = _r3;
+	register unsigned long r4 asm("r4") = _r4;
+	register int ret asm ("r3");
+
+	asm volatile(
+		"       sc\n"
+		"	bns+	1f\n"
+		"	neg	%0, %0\n"
+		"1:\n"
+	: "=r" (ret), "+r" (r4), "+r" (r0)
+	: "r" (r3)
+	: "memory", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "cr0", "ctr");
+
+	return ret;
+}
+
+static __always_inline
+int gettimeofday_fallback(struct __kernel_old_timeval *_tv, struct timezone *_tz)
+{
+	return do_syscall_2(__NR_gettimeofday, (unsigned long)_tv, (unsigned long)_tz);
+}
+
+static __always_inline
+int clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
+{
+	return do_syscall_2(__NR_clock_gettime, _clkid, (unsigned long)_ts);
+}
+
+static __always_inline
+int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
+{
+	return do_syscall_2(__NR_clock_getres, _clkid, (unsigned long)_ts);
+}
+
+#ifdef CONFIG_VDSO32
+
+#define BUILD_VDSO32		1
+
+static __always_inline
+int clock_gettime32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
+{
+	return do_syscall_2(__NR_clock_gettime, _clkid, (unsigned long)_ts);
+}
+
+static __always_inline
+int clock_getres32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
+{
+	return do_syscall_2(__NR_clock_getres, _clkid, (unsigned long)_ts);
+}
+#endif
+
+static __always_inline u64 __arch_get_hw_counter(s32 clock_mode)
+{
+	return get_tb();
+}
+
+const struct vdso_data *__arch_get_vdso_data(void);
+
+static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
+{
+	return !__USE_RTC();
+}
+#define vdso_clocksource_ok vdso_clocksource_ok
+
+/*
+ * powerpc specific delta calculation.
+ *
+ * This variant removes the masking of the subtraction because the
+ * clocksource mask of all VDSO capable clocksources on powerpc is U64_MAX
+ * which would result in a pointless operation. The compiler cannot
+ * optimize it away as the mask comes from the vdso data and is not compile
+ * time constant.
+ */
+static __always_inline u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult)
+{
+	return (cycles - last) * mult;
+}
+#define vdso_calc_delta vdso_calc_delta
+
+#ifndef __powerpc64__
+static __always_inline u64 vdso_shift_ns(u64 ns, unsigned long shift)
+{
+	u32 hi = ns >> 32;
+	u32 lo = ns;
+
+	lo >>= shift;
+	lo |= hi << (32 - shift);
+	hi >>= shift;
+
+	if (likely(hi == 0))
+		return lo;
+
+	return ((u64)hi << 32) | lo;
+}
+#define vdso_shift_ns vdso_shift_ns
+#endif
+
+#ifdef __powerpc64__
+int __c_kernel_clock_gettime(clockid_t clock, struct __kernel_timespec *ts,
+			     const struct vdso_data *vd);
+int __c_kernel_clock_getres(clockid_t clock_id, struct __kernel_timespec *res,
+			    const struct vdso_data *vd);
+#else
+int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
+			     const struct vdso_data *vd);
+int __c_kernel_clock_getres(clockid_t clock_id, struct old_timespec32 *res,
+			    const struct vdso_data *vd);
+#endif
+int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
+			    const struct vdso_data *vd);
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time,
+				    const struct vdso_data *vd);
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_GETTIMEOFDAY_H */
diff --git a/arch/powerpc/kernel/vdso32/vgettimeofday.c b/arch/powerpc/kernel/vdso32/vgettimeofday.c
new file mode 100644
index 000000000000..0b9ab4c22ef2
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/vgettimeofday.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Powerpc userspace implementations of gettimeofday() and similar.
+ */
+#include <linux/time.h>
+#include <linux/types.h>
+
+int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
+			     const struct vdso_data *vd)
+{
+	return __cvdso_clock_gettime32_data(vd, clock, ts);
+}
+
+int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_gettimeofday_data(vd, tv, tz);
+}
+
+int __c_kernel_clock_getres(clockid_t clock_id, struct old_timespec32 *res,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_clock_getres_time32_data(vd, clock_id, res);
+}
+
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time, const struct vdso_data *vd)
+{
+	return __cvdso_time_data(vd, time);
+}
diff --git a/arch/powerpc/kernel/vdso64/vgettimeofday.c b/arch/powerpc/kernel/vdso64/vgettimeofday.c
new file mode 100644
index 000000000000..5b5500058344
--- /dev/null
+++ b/arch/powerpc/kernel/vdso64/vgettimeofday.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Powerpc userspace implementations of gettimeofday() and similar.
+ */
+#include <linux/time.h>
+#include <linux/types.h>
+
+int __c_kernel_clock_gettime(clockid_t clock, struct __kernel_timespec *ts,
+			     const struct vdso_data *vd)
+{
+	return __cvdso_clock_gettime_data(vd, clock, ts);
+}
+
+int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_gettimeofday_data(vd, tv, tz);
+}
+
+int __c_kernel_clock_getres(clockid_t clock_id, struct __kernel_timespec *res,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_clock_getres_data(vd, clock_id, res);
+}
+
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time, const struct vdso_data *vd)
+{
+	return __cvdso_time_data(vd, time);
+}
-- 
2.25.0


^ permalink raw reply related

* [PATCH v10 4/5] powerpc/vdso: Switch VDSO to generic C implementation.
From: Christophe Leroy @ 2020-08-05  7:09 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl,
	anton
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev
In-Reply-To: <cover.1596611196.git.christophe.leroy@csgroup.eu>

For VDSO32 on PPC64, we create a fake 32 bits config, on the same
principle as MIPS architecture, in order to get the correct parts of
the different asm header files.

With the C VDSO, the performance is slightly lower, but it is worth
it as it will ease maintenance and evolution, and also brings clocks
that are not supported with the ASM VDSO.

On an 8xx at 132 MHz, vdsotest with the ASM VDSO:
gettimeofday:    vdso: 828 nsec/call
clock-getres-realtime-coarse:    vdso: 391 nsec/call
clock-gettime-realtime-coarse:    vdso: 614 nsec/call
clock-getres-realtime:    vdso: 460 nsec/call
clock-gettime-realtime:    vdso: 876 nsec/call
clock-getres-monotonic-coarse:    vdso: 399 nsec/call
clock-gettime-monotonic-coarse:    vdso: 691 nsec/call
clock-getres-monotonic:    vdso: 460 nsec/call
clock-gettime-monotonic:    vdso: 1026 nsec/call

On an 8xx at 132 MHz, vdsotest with the C VDSO:
gettimeofday:    vdso: 955 nsec/call
clock-getres-realtime-coarse:    vdso: 545 nsec/call
clock-gettime-realtime-coarse:    vdso: 592 nsec/call
clock-getres-realtime:    vdso: 545 nsec/call
clock-gettime-realtime:    vdso: 941 nsec/call
clock-getres-monotonic-coarse:    vdso: 545 nsec/call
clock-gettime-monotonic-coarse:    vdso: 591 nsec/call
clock-getres-monotonic:    vdso: 545 nsec/call
clock-gettime-monotonic:    vdso: 940 nsec/call

It is even better for gettime with monotonic clocks.

Unsupported clocks with ASM VDSO:
clock-gettime-boottime:    vdso: 3851 nsec/call
clock-gettime-tai:    vdso: 3852 nsec/call
clock-gettime-monotonic-raw:    vdso: 3396 nsec/call

Same clocks with C VDSO:
clock-gettime-tai:    vdso: 941 nsec/call
clock-gettime-monotonic-raw:    vdso: 1001 nsec/call
clock-gettime-monotonic-coarse:    vdso: 591 nsec/call

On an 8321E at 333 MHz, vdsotest with the ASM VDSO:
gettimeofday:    vdso: 220 nsec/call
clock-getres-realtime-coarse:    vdso: 102 nsec/call
clock-gettime-realtime-coarse:    vdso: 178 nsec/call
clock-getres-realtime:    vdso: 129 nsec/call
clock-gettime-realtime:    vdso: 235 nsec/call
clock-getres-monotonic-coarse:    vdso: 105 nsec/call
clock-gettime-monotonic-coarse:    vdso: 208 nsec/call
clock-getres-monotonic:    vdso: 129 nsec/call
clock-gettime-monotonic:    vdso: 274 nsec/call

On an 8321E at 333 MHz, vdsotest with the C VDSO:
gettimeofday:    vdso: 272 nsec/call
clock-getres-realtime-coarse:    vdso: 160 nsec/call
clock-gettime-realtime-coarse:    vdso: 184 nsec/call
clock-getres-realtime:    vdso: 166 nsec/call
clock-gettime-realtime:    vdso: 281 nsec/call
clock-getres-monotonic-coarse:    vdso: 160 nsec/call
clock-gettime-monotonic-coarse:    vdso: 184 nsec/call
clock-getres-monotonic:    vdso: 169 nsec/call
clock-gettime-monotonic:    vdso: 275 nsec/call

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9:
- Rebased (Impact on arch/powerpc/kernel/vdso??/Makefile

v7:
- Split out preparatory changes in a new preceding patch
- Added -fasynchronous-unwind-tables to CC flags.

v6:
- Added missing prototypes in asm/vdso/gettimeofday.h for __c_kernel_ functions.
- Using STACK_FRAME_OVERHEAD instead of INT_FRAME_SIZE
- Rebased on powerpc/merge as of 7 Apr 2020
- Fixed build failure with gcc 9
- Added a patch to create asm/vdso/processor.h and more cpu_relax() in it
---
 arch/powerpc/Kconfig                       |   2 +
 arch/powerpc/include/asm/vdso/vsyscall.h   |  25 ++
 arch/powerpc/include/asm/vdso_datapage.h   |  40 +--
 arch/powerpc/kernel/asm-offsets.c          |  49 +---
 arch/powerpc/kernel/time.c                 |  91 +------
 arch/powerpc/kernel/vdso.c                 |   5 +-
 arch/powerpc/kernel/vdso32/Makefile        |  32 ++-
 arch/powerpc/kernel/vdso32/config-fake32.h |  34 +++
 arch/powerpc/kernel/vdso32/gettimeofday.S  | 291 +--------------------
 arch/powerpc/kernel/vdso64/Makefile        |  23 +-
 arch/powerpc/kernel/vdso64/gettimeofday.S  | 242 +----------------
 11 files changed, 143 insertions(+), 691 deletions(-)
 create mode 100644 arch/powerpc/include/asm/vdso/vsyscall.h
 create mode 100644 arch/powerpc/kernel/vdso32/config-fake32.h

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 8c7656cc10eb..9977ab939b42 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -171,6 +171,7 @@ config PPC
 	select GENERIC_STRNCPY_FROM_USER
 	select GENERIC_STRNLEN_USER
 	select GENERIC_TIME_VSYSCALL
+	select GENERIC_GETTIMEOFDAY
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_HUGE_VMAP		if PPC_BOOK3S_64 && PPC_RADIX_MMU
 	select HAVE_ARCH_JUMP_LABEL
@@ -202,6 +203,7 @@ config PPC
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FUNCTION_TRACER
 	select HAVE_GCC_PLUGINS			if GCC_VERSION >= 50200   # plugin support on gcc <= 5.1 is buggy on PPC
+	select HAVE_GENERIC_VDSO
 	select HAVE_HW_BREAKPOINT		if PERF_EVENTS && (PPC_BOOK3S || PPC_8xx)
 	select HAVE_IDE
 	select HAVE_IOREMAP_PROT
diff --git a/arch/powerpc/include/asm/vdso/vsyscall.h b/arch/powerpc/include/asm/vdso/vsyscall.h
new file mode 100644
index 000000000000..c56a030c0623
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/vsyscall.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_VDSO_VSYSCALL_H
+#define __ASM_VDSO_VSYSCALL_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/timekeeper_internal.h>
+#include <asm/vdso_datapage.h>
+
+/*
+ * Update the vDSO data page to keep in sync with kernel timekeeping.
+ */
+static __always_inline
+struct vdso_data *__arch_get_k_vdso_data(void)
+{
+	return vdso_data->data;
+}
+#define __arch_get_k_vdso_data __arch_get_k_vdso_data
+
+/* The asm-generic header needs to be included after the definitions above */
+#include <asm-generic/vdso/vsyscall.h>
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_VSYSCALL_H */
diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
index b9ef6cf50ea5..c4d320504d26 100644
--- a/arch/powerpc/include/asm/vdso_datapage.h
+++ b/arch/powerpc/include/asm/vdso_datapage.h
@@ -36,6 +36,7 @@
 
 #include <linux/unistd.h>
 #include <linux/time.h>
+#include <vdso/datapage.h>
 
 #define SYSCALL_MAP_SIZE      ((NR_syscalls + 31) / 32)
 
@@ -45,7 +46,7 @@
 
 #ifdef CONFIG_PPC64
 
-struct vdso_data {
+struct vdso_arch_data {
 	__u8  eye_catcher[16];		/* Eyecatcher: SYSTEMCFG:PPC64	0x00 */
 	struct {			/* Systemcfg version numbers	     */
 		__u32 major;		/* Major number			0x10 */
@@ -59,13 +60,13 @@ struct vdso_data {
 	__u32 processor;		/* Processor type		0x1C */
 	__u64 processorCount;		/* # of physical processors	0x20 */
 	__u64 physicalMemorySize;	/* Size of real memory(B)	0x28 */
-	__u64 tb_orig_stamp;		/* Timebase at boot		0x30 */
+	__u64 tb_orig_stamp;		/* (NU) Timebase at boot	0x30 */
 	__u64 tb_ticks_per_sec;		/* Timebase tics / sec		0x38 */
-	__u64 tb_to_xs;			/* Inverse of TB to 2^20	0x40 */
-	__u64 stamp_xsec;		/*				0x48 */
-	__u64 tb_update_count;		/* Timebase atomicity ctr	0x50 */
-	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x58 */
-	__u32 tz_dsttime;		/* Type of dst correction	0x5C */
+	__u64 tb_to_xs;			/* (NU) Inverse of TB to 2^20	0x40 */
+	__u64 stamp_xsec;		/* (NU)				0x48 */
+	__u64 tb_update_count;		/* (NU) Timebase atomicity ctr	0x50 */
+	__u32 tz_minuteswest;		/* (NU) Min. west of Greenwich	0x58 */
+	__u32 tz_dsttime;		/* (NU) Type of dst correction	0x5C */
 	__u32 dcache_size;		/* L1 d-cache size		0x60 */
 	__u32 dcache_line_size;		/* L1 d-cache line size		0x64 */
 	__u32 icache_size;		/* L1 i-cache size		0x68 */
@@ -78,14 +79,10 @@ struct vdso_data {
 	__u32 icache_block_size;		/* L1 i-cache block size     */
 	__u32 dcache_log_block_size;		/* L1 d-cache log block size */
 	__u32 icache_log_block_size;		/* L1 i-cache log block size */
-	__u32 stamp_sec_fraction;		/* fractional seconds of stamp_xtime */
-	__s32 wtom_clock_nsec;			/* Wall to monotonic clock nsec */
-	__s64 wtom_clock_sec;			/* Wall to monotonic clock sec */
-	__s64 stamp_xtime_sec;			/* xtime secs as at tb_orig_stamp */
-	__s64 stamp_xtime_nsec;			/* xtime nsecs as at tb_orig_stamp */
-	__u32 hrtimer_res;			/* hrtimer resolution */
    	__u32 syscall_map_64[SYSCALL_MAP_SIZE]; /* map of syscalls  */
    	__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
+
+	struct vdso_data data[CS_BASES];
 };
 
 #else /* CONFIG_PPC64 */
@@ -93,26 +90,15 @@ struct vdso_data {
 /*
  * And here is the simpler 32 bits version
  */
-struct vdso_data {
-	__u64 tb_orig_stamp;		/* Timebase at boot		0x30 */
+struct vdso_arch_data {
 	__u64 tb_ticks_per_sec;		/* Timebase tics / sec		0x38 */
-	__u64 tb_to_xs;			/* Inverse of TB to 2^20	0x40 */
-	__u64 stamp_xsec;		/*				0x48 */
-	__u32 tb_update_count;		/* Timebase atomicity ctr	0x50 */
-	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x58 */
-	__u32 tz_dsttime;		/* Type of dst correction	0x5C */
-	__s32 wtom_clock_sec;			/* Wall to monotonic clock */
-	__s32 wtom_clock_nsec;
-	__s32 stamp_xtime_sec;		/* xtime seconds as at tb_orig_stamp */
-	__s32 stamp_xtime_nsec;		/* xtime nsecs as at tb_orig_stamp */
-	__u32 stamp_sec_fraction;	/* fractional seconds of stamp_xtime */
-	__u32 hrtimer_res;		/* hrtimer resolution */
    	__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
+	struct vdso_data data[CS_BASES];
 };
 
 #endif /* CONFIG_PPC64 */
 
-extern struct vdso_data *vdso_data;
+extern struct vdso_arch_data *vdso_data;
 
 #else /* __ASSEMBLY__ */
 
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 8711c2164b45..684260186dbf 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -397,47 +397,16 @@ int main(void)
 #endif /* ! CONFIG_PPC64 */
 
 	/* datapage offsets for use by vdso */
-	OFFSET(CFG_TB_ORIG_STAMP, vdso_data, tb_orig_stamp);
-	OFFSET(CFG_TB_TICKS_PER_SEC, vdso_data, tb_ticks_per_sec);
-	OFFSET(CFG_TB_TO_XS, vdso_data, tb_to_xs);
-	OFFSET(CFG_TB_UPDATE_COUNT, vdso_data, tb_update_count);
-	OFFSET(CFG_TZ_MINUTEWEST, vdso_data, tz_minuteswest);
-	OFFSET(CFG_TZ_DSTTIME, vdso_data, tz_dsttime);
-	OFFSET(CFG_SYSCALL_MAP32, vdso_data, syscall_map_32);
-	OFFSET(WTOM_CLOCK_SEC, vdso_data, wtom_clock_sec);
-	OFFSET(WTOM_CLOCK_NSEC, vdso_data, wtom_clock_nsec);
-	OFFSET(STAMP_XTIME_SEC, vdso_data, stamp_xtime_sec);
-	OFFSET(STAMP_XTIME_NSEC, vdso_data, stamp_xtime_nsec);
-	OFFSET(STAMP_SEC_FRAC, vdso_data, stamp_sec_fraction);
-	OFFSET(CLOCK_HRTIMER_RES, vdso_data, hrtimer_res);
+	OFFSET(VDSO_DATA_OFFSET, vdso_arch_data, data);
+	OFFSET(CFG_TB_TICKS_PER_SEC, vdso_arch_data, tb_ticks_per_sec);
+	OFFSET(CFG_SYSCALL_MAP32, vdso_arch_data, syscall_map_32);
 #ifdef CONFIG_PPC64
-	OFFSET(CFG_ICACHE_BLOCKSZ, vdso_data, icache_block_size);
-	OFFSET(CFG_DCACHE_BLOCKSZ, vdso_data, dcache_block_size);
-	OFFSET(CFG_ICACHE_LOGBLOCKSZ, vdso_data, icache_log_block_size);
-	OFFSET(CFG_DCACHE_LOGBLOCKSZ, vdso_data, dcache_log_block_size);
-	OFFSET(CFG_SYSCALL_MAP64, vdso_data, syscall_map_64);
-	OFFSET(TVAL64_TV_SEC, __kernel_old_timeval, tv_sec);
-	OFFSET(TVAL64_TV_USEC, __kernel_old_timeval, tv_usec);
-#endif
-	OFFSET(TSPC64_TV_SEC, __kernel_timespec, tv_sec);
-	OFFSET(TSPC64_TV_NSEC, __kernel_timespec, tv_nsec);
-	OFFSET(TVAL32_TV_SEC, old_timeval32, tv_sec);
-	OFFSET(TVAL32_TV_USEC, old_timeval32, tv_usec);
-	OFFSET(TSPC32_TV_SEC, old_timespec32, tv_sec);
-	OFFSET(TSPC32_TV_NSEC, old_timespec32, tv_nsec);
-	/* timeval/timezone offsets for use by vdso */
-	OFFSET(TZONE_TZ_MINWEST, timezone, tz_minuteswest);
-	OFFSET(TZONE_TZ_DSTTIME, timezone, tz_dsttime);
-
-	/* Other bits used by the vdso */
-	DEFINE(CLOCK_REALTIME, CLOCK_REALTIME);
-	DEFINE(CLOCK_MONOTONIC, CLOCK_MONOTONIC);
-	DEFINE(CLOCK_REALTIME_COARSE, CLOCK_REALTIME_COARSE);
-	DEFINE(CLOCK_MONOTONIC_COARSE, CLOCK_MONOTONIC_COARSE);
-	DEFINE(CLOCK_MAX, CLOCK_TAI);
-	DEFINE(NSEC_PER_SEC, NSEC_PER_SEC);
-	DEFINE(EINVAL, EINVAL);
-	DEFINE(KTIME_LOW_RES, KTIME_LOW_RES);
+	OFFSET(CFG_ICACHE_BLOCKSZ, vdso_arch_data, icache_block_size);
+	OFFSET(CFG_DCACHE_BLOCKSZ, vdso_arch_data, dcache_block_size);
+	OFFSET(CFG_ICACHE_LOGBLOCKSZ, vdso_arch_data, icache_log_block_size);
+	OFFSET(CFG_DCACHE_LOGBLOCKSZ, vdso_arch_data, dcache_log_block_size);
+	OFFSET(CFG_SYSCALL_MAP64, vdso_arch_data, syscall_map_64);
+#endif
 
 #ifdef CONFIG_BUG
 	DEFINE(BUG_ENTRY_SIZE, sizeof(struct bug_entry));
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 6fcae436ae51..b63b1f97a1b3 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -91,6 +91,7 @@ static struct clocksource clocksource_timebase = {
 	.flags        = CLOCK_SOURCE_IS_CONTINUOUS,
 	.mask         = CLOCKSOURCE_MASK(64),
 	.read         = timebase_read,
+	.vdso_clock_mode	= VDSO_CLOCKMODE_ARCHTIMER,
 };
 
 #define DECREMENTER_DEFAULT_MAX 0x7FFFFFFF
@@ -855,95 +856,6 @@ static notrace u64 timebase_read(struct clocksource *cs)
 	return (u64)get_tb();
 }
 
-
-void update_vsyscall(struct timekeeper *tk)
-{
-	struct timespec64 xt;
-	struct clocksource *clock = tk->tkr_mono.clock;
-	u32 mult = tk->tkr_mono.mult;
-	u32 shift = tk->tkr_mono.shift;
-	u64 cycle_last = tk->tkr_mono.cycle_last;
-	u64 new_tb_to_xs, new_stamp_xsec;
-	u64 frac_sec;
-
-	if (clock != &clocksource_timebase)
-		return;
-
-	xt.tv_sec = tk->xtime_sec;
-	xt.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
-
-	/* Make userspace gettimeofday spin until we're done. */
-	++vdso_data->tb_update_count;
-	smp_mb();
-
-	/*
-	 * This computes ((2^20 / 1e9) * mult) >> shift as a
-	 * 0.64 fixed-point fraction.
-	 * The computation in the else clause below won't overflow
-	 * (as long as the timebase frequency is >= 1.049 MHz)
-	 * but loses precision because we lose the low bits of the constant
-	 * in the shift.  Note that 19342813113834067 ~= 2^(20+64) / 1e9.
-	 * For a shift of 24 the error is about 0.5e-9, or about 0.5ns
-	 * over a second.  (Shift values are usually 22, 23 or 24.)
-	 * For high frequency clocks such as the 512MHz timebase clock
-	 * on POWER[6789], the mult value is small (e.g. 32768000)
-	 * and so we can shift the constant by 16 initially
-	 * (295147905179 ~= 2^(20+64-16) / 1e9) and then do the
-	 * remaining shifts after the multiplication, which gives a
-	 * more accurate result (e.g. with mult = 32768000, shift = 24,
-	 * the error is only about 1.2e-12, or 0.7ns over 10 minutes).
-	 */
-	if (mult <= 62500000 && clock->shift >= 16)
-		new_tb_to_xs = ((u64) mult * 295147905179ULL) >> (clock->shift - 16);
-	else
-		new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift);
-
-	/*
-	 * Compute the fractional second in units of 2^-32 seconds.
-	 * The fractional second is tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift
-	 * in nanoseconds, so multiplying that by 2^32 / 1e9 gives
-	 * it in units of 2^-32 seconds.
-	 * We assume shift <= 32 because clocks_calc_mult_shift()
-	 * generates shift values in the range 0 - 32.
-	 */
-	frac_sec = tk->tkr_mono.xtime_nsec << (32 - shift);
-	do_div(frac_sec, NSEC_PER_SEC);
-
-	/*
-	 * Work out new stamp_xsec value for any legacy users of systemcfg.
-	 * stamp_xsec is in units of 2^-20 seconds.
-	 */
-	new_stamp_xsec = frac_sec >> 12;
-	new_stamp_xsec += tk->xtime_sec * XSEC_PER_SEC;
-
-	/*
-	 * tb_update_count is used to allow the userspace gettimeofday code
-	 * to assure itself that it sees a consistent view of the tb_to_xs and
-	 * stamp_xsec variables.  It reads the tb_update_count, then reads
-	 * tb_to_xs and stamp_xsec and then reads tb_update_count again.  If
-	 * the two values of tb_update_count match and are even then the
-	 * tb_to_xs and stamp_xsec values are consistent.  If not, then it
-	 * loops back and reads them again until this criteria is met.
-	 */
-	vdso_data->tb_orig_stamp = cycle_last;
-	vdso_data->stamp_xsec = new_stamp_xsec;
-	vdso_data->tb_to_xs = new_tb_to_xs;
-	vdso_data->wtom_clock_sec = tk->wall_to_monotonic.tv_sec;
-	vdso_data->wtom_clock_nsec = tk->wall_to_monotonic.tv_nsec;
-	vdso_data->stamp_xtime_sec = xt.tv_sec;
-	vdso_data->stamp_xtime_nsec = xt.tv_nsec;
-	vdso_data->stamp_sec_fraction = frac_sec;
-	vdso_data->hrtimer_res = hrtimer_resolution;
-	smp_wmb();
-	++(vdso_data->tb_update_count);
-}
-
-void update_vsyscall_tz(void)
-{
-	vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
-	vdso_data->tz_dsttime = sys_tz.tz_dsttime;
-}
-
 static void __init clocksource_init(void)
 {
 	struct clocksource *clock;
@@ -1113,7 +1025,6 @@ void __init time_init(void)
 		sys_tz.tz_dsttime = 0;
 	}
 
-	vdso_data->tb_update_count = 0;
 	vdso_data->tb_ticks_per_sec = tb_ticks_per_sec;
 
 	/* initialise and enable the large decrementer (if we have one) */
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 8dad44262e75..23208a051af5 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -17,6 +17,7 @@
 #include <linux/elf.h>
 #include <linux/security.h>
 #include <linux/memblock.h>
+#include <vdso/datapage.h>
 
 #include <asm/processor.h>
 #include <asm/mmu.h>
@@ -70,10 +71,10 @@ static int vdso_ready;
  * with it, it will become dynamically allocated
  */
 static union {
-	struct vdso_data	data;
+	struct vdso_arch_data	data;
 	u8			page[PAGE_SIZE];
 } vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = &vdso_data_store.data;
+struct vdso_arch_data *vdso_data = &vdso_data_store.data;
 
 /* Format of the patch table */
 struct vdso_patch_def
diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
index 87ab1152d5ce..b922044236dd 100644
--- a/arch/powerpc/kernel/vdso32/Makefile
+++ b/arch/powerpc/kernel/vdso32/Makefile
@@ -2,7 +2,23 @@
 
 # List of files in the vdso, has to be asm only for now
 
-obj-vdso32 = sigtramp.o gettimeofday.o datapage.o cacheflush.o note.o getcpu.o
+ARCH_REL_TYPE_ABS := R_PPC_JUMP_SLOT|R_PPC_GLOB_DAT|R_PPC_ADDR32|R_PPC_ADDR24|R_PPC_ADDR16|R_PPC_ADDR16_LO|R_PPC_ADDR16_HI|R_PPC_ADDR16_HA|R_PPC_ADDR14|R_PPC_ADDR14_BRTAKEN|R_PPC_ADDR14_BRNTAKEN
+include $(srctree)/lib/vdso/Makefile
+
+obj-vdso32 = sigtramp.o datapage.o cacheflush.o note.o getcpu.o $(obj-vdso32-y)
+obj-vdso32 += gettimeofday.o
+
+ifneq ($(c-gettimeofday-y),)
+  ifdef CONFIG_PPC64
+    CFLAGS_vgettimeofday.o += -include $(srctree)/$(src)/config-fake32.h
+  endif
+  CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
+  CFLAGS_vgettimeofday.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
+  CFLAGS_vgettimeofday.o += $(call cc-option, -fno-stack-protector)
+  CFLAGS_vgettimeofday.o += -DDISABLE_BRANCH_PROFILING
+  CFLAGS_vgettimeofday.o += -ffreestanding -fasynchronous-unwind-tables
+  CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE)
+endif
 
 # Build rules
 
@@ -15,6 +31,7 @@ endif
 CC32FLAGS :=
 ifdef CONFIG_PPC64
 CC32FLAGS += -m32
+KBUILD_CFLAGS := $(filter-out -mcmodel=medium,$(KBUILD_CFLAGS))
 endif
 
 targets := $(obj-vdso32) vdso32.so vdso32.so.dbg
@@ -23,6 +40,7 @@ obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32))
 GCOV_PROFILE := n
 KCOV_INSTRUMENT := n
 UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
 
 ccflags-y := -shared -fno-common -fno-builtin -nostdlib \
 	-Wl,-soname=linux-vdso32.so.1 -Wl,--hash-style=both
@@ -36,8 +54,8 @@ CPPFLAGS_vdso32.lds += -P -C -Upowerpc
 $(obj)/vdso32_wrapper.o : $(obj)/vdso32.so
 
 # link rule for the .so file, .lds has to be first
-$(obj)/vdso32.so.dbg: $(src)/vdso32.lds $(obj-vdso32) FORCE
-	$(call if_changed,vdso32ld)
+$(obj)/vdso32.so.dbg: $(src)/vdso32.lds $(obj-vdso32) $(obj)/vgettimeofday.o FORCE
+	$(call if_changed,vdso32ld_and_check)
 
 # strip rule for the .so file
 $(obj)/%.so: OBJCOPYFLAGS := -S
@@ -47,12 +65,16 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
 # assembly rules for the .S files
 $(obj-vdso32): %.o: %.S FORCE
 	$(call if_changed_dep,vdso32as)
+$(obj)/vgettimeofday.o: %.o: %.c FORCE
+	$(call if_changed_dep,vdso32cc)
 
 # actual build commands
-quiet_cmd_vdso32ld = VDSO32L $@
-      cmd_vdso32ld = $(VDSOCC) $(c_flags) $(CC32FLAGS) -o $@ $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn) -Wl,-T$(filter %.lds,$^) $(filter %.o,$^)
+quiet_cmd_vdso32ld_and_check = VDSO32L $@
+      cmd_vdso32ld_and_check = $(VDSOCC) $(c_flags) $(CC32FLAGS) -o $@ $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn) -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) ; $(cmd_vdso_check)
 quiet_cmd_vdso32as = VDSO32A $@
       cmd_vdso32as = $(VDSOCC) $(a_flags) $(CC32FLAGS) -c -o $@ $<
+quiet_cmd_vdso32cc = VDSO32C $@
+      cmd_vdso32cc = $(VDSOCC) $(c_flags) $(CC32FLAGS) -c -o $@ $<
 
 # install commands for the unstripped file
 quiet_cmd_vdso_install = INSTALL $@
diff --git a/arch/powerpc/kernel/vdso32/config-fake32.h b/arch/powerpc/kernel/vdso32/config-fake32.h
new file mode 100644
index 000000000000..e16041fc15c9
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/config-fake32.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * In case of a 32 bit VDSO for a 64 bit kernel fake a 32 bit kernel
+ * configuration.
+ */
+
+#undef CONFIG_PPC64
+#undef CONFIG_64BIT
+#define CONFIG_PPC32
+#define CONFIG_32BIT 1
+#define CONFIG_GENERIC_ATOMIC64 1
+
+#ifdef CONFIG_PPC_BOOK3S_64
+#undef CONFIG_PPC_BOOK3S_64
+#undef CONFIG_PPC_PSERIES
+#define CONFIG_PPC_BOOK3S_32
+#else
+#define CONFIG_PPC_MMU_NOHASH_32
+#define CONFIG_FSL_BOOKE
+#endif
+
+#define CONFIG_TASK_SIZE	0
+#undef CONFIG_MMIOWB
+#undef CONFIG_PPC_SPLPAR
+#undef CONFIG_SPARSEMEM
+#undef CONFIG_PGTABLE_LEVELS
+#define CONFIG_PGTABLE_LEVELS	2
+#undef CONFIG_TRANSPARENT_HUGEPAGE
+#undef CONFIG_SPARSEMEM_VMEMMAP
+#undef CONFIG_FLATMEM
+#define CONFIG_FLATMEM
+#undef CONFIG_PPC_INDIRECT_MMIO
+#undef CONFIG_PPC_INDIRECT_PIO
+#undef CONFIG_EEH
diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
index e7f8f9f1b3f4..fd7b01c51281 100644
--- a/arch/powerpc/kernel/vdso32/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
@@ -12,13 +12,7 @@
 #include <asm/vdso_datapage.h>
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
-
-/* Offset for the low 32-bit part of a field of long type */
-#ifdef CONFIG_PPC64
-#define LOPART	4
-#else
-#define LOPART	0
-#endif
+#include <asm/vdso/gettimeofday.h>
 
 	.text
 /*
@@ -28,32 +22,7 @@
  *
  */
 V_FUNCTION_BEGIN(__kernel_gettimeofday)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr.	r10,r3			/* r10 saves tv */
-	mr	r11,r4			/* r11 saves tz */
-	get_datapage	r9, r0
-	beq	3f
-	LOAD_REG_IMMEDIATE(r7, 1000000)	/* load up USEC_PER_SEC */
-	bl	__do_get_tspec@local	/* get sec/usec from tb & kernel */
-	stw	r3,TVAL32_TV_SEC(r10)
-	stw	r4,TVAL32_TV_USEC(r10)
-
-3:	cmplwi	r11,0			/* check if tz is NULL */
-	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0
-	beqlr
-
-	lwz	r4,CFG_TZ_MINUTEWEST(r9)/* fill tz */
-	lwz	r5,CFG_TZ_DSTTIME(r9)
-	stw	r4,TZONE_TZ_MINWEST(r11)
-	stw	r5,TZONE_TZ_DSTTIME(r11)
-
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_gettimeofday
 V_FUNCTION_END(__kernel_gettimeofday)
 
 /*
@@ -63,127 +32,7 @@ V_FUNCTION_END(__kernel_gettimeofday)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_gettime)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmpli	cr0,r3,CLOCK_REALTIME
-	cmpli	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
-
-	cmpli	cr5,r3,CLOCK_REALTIME_COARSE
-	cmpli	cr6,r3,CLOCK_MONOTONIC_COARSE
-	cror	cr5*4+eq,cr5*4+eq,cr6*4+eq
-
-	cror	cr0*4+eq,cr0*4+eq,cr5*4+eq
-	bne	cr0, .Lgettime_fallback
-
-	mflr	r12			/* r12 saves lr */
-  .cfi_register lr,r12
-	mr	r11,r4			/* r11 saves tp */
-	get_datapage	r9, r0
-	LOAD_REG_IMMEDIATE(r7, NSEC_PER_SEC)	/* load up NSEC_PER_SEC */
-	beq	cr5, .Lcoarse_clocks
-.Lprecise_clocks:
-	bl	__do_get_tspec@local	/* get sec/nsec from tb & kernel */
-	bne	cr1, .Lfinish		/* not monotonic -> all done */
-
-	/*
-	 * CLOCK_MONOTONIC
-	 */
-
-	/* now we must fixup using wall to monotonic. We need to snapshot
-	 * that value and do the counter trick again. Fortunately, we still
-	 * have the counter value in r8 that was returned by __do_get_xsec.
-	 * At this point, r3,r4 contain our sec/nsec values, r5 and r6
-	 * can be used, r7 contains NSEC_PER_SEC.
-	 */
-
-	lwz	r5,(WTOM_CLOCK_SEC+LOPART)(r9)
-	lwz	r6,WTOM_CLOCK_NSEC(r9)
-
-	/* We now have our offset in r5,r6. We create a fake dependency
-	 * on that value and re-check the counter
-	 */
-	or	r0,r6,r5
-	xor	r0,r0,r0
-	add	r9,r9,r0
-	lwz	r0,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-        cmpl    cr0,r8,r0		/* check if updated */
-	bne-	.Lprecise_clocks
-	b	.Lfinish_monotonic
-
-	/*
-	 * For coarse clocks we get data directly from the vdso data page, so
-	 * we don't need to call __do_get_tspec, but we still need to do the
-	 * counter trick.
-	 */
-.Lcoarse_clocks:
-	lwz	r8,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-	andi.	r0,r8,1                 /* pending update ? loop */
-	bne-	.Lcoarse_clocks
-	add	r9,r9,r0		/* r0 is already 0 */
-
-	/*
-	 * CLOCK_REALTIME_COARSE, below values are needed for MONOTONIC_COARSE
-	 * too
-	 */
-	lwz	r3,STAMP_XTIME_SEC+LOPART(r9)
-	lwz	r4,STAMP_XTIME_NSEC+LOPART(r9)
-	bne	cr6,1f
-
-	/* CLOCK_MONOTONIC_COARSE */
-	lwz	r5,(WTOM_CLOCK_SEC+LOPART)(r9)
-	lwz	r6,WTOM_CLOCK_NSEC(r9)
-
-	/* check if counter has updated */
-	or	r0,r6,r5
-1:	or	r0,r0,r3
-	or	r0,r0,r4
-	xor	r0,r0,r0
-	add	r3,r3,r0
-	lwz	r0,CFG_TB_UPDATE_COUNT+LOPART(r9)
-	cmpl	cr0,r0,r8               /* check if updated */
-	bne-	.Lcoarse_clocks
-
-	/* Counter has not updated, so continue calculating proper values for
-	 * sec and nsec if monotonic coarse, or just return with the proper
-	 * values for realtime.
-	 */
-	bne	cr6, .Lfinish
-
-	/* Calculate and store result. Note that this mimics the C code,
-	 * which may cause funny results if nsec goes negative... is that
-	 * possible at all ?
-	 */
-.Lfinish_monotonic:
-	add	r3,r3,r5
-	add	r4,r4,r6
-	cmpw	cr0,r4,r7
-	cmpwi	cr1,r4,0
-	blt	1f
-	subf	r4,r7,r4
-	addi	r3,r3,1
-1:	bge	cr1, .Lfinish
-	addi	r3,r3,-1
-	add	r4,r4,r7
-
-.Lfinish:
-	stw	r3,TSPC32_TV_SEC(r11)
-	stw	r4,TSPC32_TV_NSEC(r11)
-
-	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-.Lgettime_fallback:
-	li	r0,__NR_clock_gettime
-  .cfi_restore lr
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
 
@@ -194,37 +43,7 @@ V_FUNCTION_END(__kernel_clock_gettime)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_getres)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmplwi	cr0, r3, CLOCK_MAX
-	cmpwi	cr1, r3, CLOCK_REALTIME_COARSE
-	cmpwi	cr7, r3, CLOCK_MONOTONIC_COARSE
-	bgt	cr0, 99f
-	LOAD_REG_IMMEDIATE(r5, KTIME_LOW_RES)
-	beq	cr1, 1f
-	beq	cr7, 1f
-
-	mflr	r12
-  .cfi_register lr,r12
-	get_datapage	r3, r0
-	lwz	r5, CLOCK_HRTIMER_RES(r3)
-	mtlr	r12
-1:	li	r3,0
-	cmpli	cr0,r4,0
-	crclr	cr0*4+so
-	beqlr
-	stw	r3,TSPC32_TV_SEC(r4)
-	stw	r5,TSPC32_TV_NSEC(r4)
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-99:
-	li	r0,__NR_clock_getres
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_getres
 V_FUNCTION_END(__kernel_clock_getres)
 
 
@@ -235,105 +54,5 @@ V_FUNCTION_END(__kernel_clock_getres)
  *
  */
 V_FUNCTION_BEGIN(__kernel_time)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr	r11,r3			/* r11 holds t */
-	get_datapage	r9, r0
-
-	lwz	r3,STAMP_XTIME_SEC+LOPART(r9)
-
-	cmplwi	r11,0			/* check if t is NULL */
-	mtlr	r12
-	crclr	cr0*4+so
-	beqlr
-	stw	r3,0(r11)		/* store result at *t */
-	blr
-  .cfi_endproc
+	cvdso_call_time __c_kernel_time
 V_FUNCTION_END(__kernel_time)
-
-/*
- * This is the core of clock_gettime() and gettimeofday(),
- * it returns the current time in r3 (seconds) and r4.
- * On entry, r7 gives the resolution of r4, either USEC_PER_SEC
- * or NSEC_PER_SEC, giving r4 in microseconds or nanoseconds.
- * It expects the datapage ptr in r9 and doesn't clobber it.
- * It clobbers r0, r5 and r6.
- * On return, r8 contains the counter value that can be reused.
- * This clobbers cr0 but not any other cr field.
- */
-__do_get_tspec:
-  .cfi_startproc
-	/* Check for update count & load values. We use the low
-	 * order 32 bits of the update count
-	 */
-1:	lwz	r8,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-	andi.	r0,r8,1			/* pending update ? loop */
-	bne-	1b
-	xor	r0,r8,r8		/* create dependency */
-	add	r9,r9,r0
-
-	/* Load orig stamp (offset to TB) */
-	lwz	r5,CFG_TB_ORIG_STAMP(r9)
-	lwz	r6,(CFG_TB_ORIG_STAMP+4)(r9)
-
-	/* Get a stable TB value */
-2:	MFTBU(r3)
-	MFTBL(r4)
-	MFTBU(r0)
-	cmplw	cr0,r3,r0
-	bne-	2b
-
-	/* Subtract tb orig stamp and shift left 12 bits.
-	 */
-	subfc	r4,r6,r4
-	subfe	r0,r5,r3
-	slwi	r0,r0,12
-	rlwimi.	r0,r4,12,20,31
-	slwi	r4,r4,12
-
-	/*
-	 * Load scale factor & do multiplication.
-	 * We only use the high 32 bits of the tb_to_xs value.
-	 * Even with a 1GHz timebase clock, the high 32 bits of
-	 * tb_to_xs will be at least 4 million, so the error from
-	 * ignoring the low 32 bits will be no more than 0.25ppm.
-	 * The error will just make the clock run very very slightly
-	 * slow until the next time the kernel updates the VDSO data,
-	 * at which point the clock will catch up to the kernel's value,
-	 * so there is no long-term error accumulation.
-	 */
-	lwz	r5,CFG_TB_TO_XS(r9)	/* load values */
-	mulhwu	r4,r4,r5
-	li	r3,0
-
-	beq+	4f			/* skip high part computation if 0 */
-	mulhwu	r3,r0,r5
-	mullw	r5,r0,r5
-	addc	r4,r4,r5
-	addze	r3,r3
-4:
-	/* At this point, we have seconds since the xtime stamp
-	 * as a 32.32 fixed-point number in r3 and r4.
-	 * Load & add the xtime stamp.
-	 */
-	lwz	r5,STAMP_XTIME_SEC+LOPART(r9)
-	lwz	r6,STAMP_SEC_FRAC(r9)
-	addc	r4,r4,r6
-	adde	r3,r3,r5
-
-	/* We create a fake dependency on the result in r3/r4
-	 * and re-check the counter
-	 */
-	or	r6,r4,r3
-	xor	r0,r6,r6
-	add	r9,r9,r0
-	lwz	r0,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-        cmplw	cr0,r8,r0		/* check if updated */
-	bne-	1b
-
-	mulhwu	r4,r4,r7		/* convert to micro or nanoseconds */
-
-	blr
-  .cfi_endproc
diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
index 38c317f25141..7890d889f9c5 100644
--- a/arch/powerpc/kernel/vdso64/Makefile
+++ b/arch/powerpc/kernel/vdso64/Makefile
@@ -1,8 +1,20 @@
 # SPDX-License-Identifier: GPL-2.0
 # List of files in the vdso, has to be asm only for now
 
+ARCH_REL_TYPE_ABS := R_PPC_JUMP_SLOT|R_PPC_GLOB_DAT|R_PPC_ADDR32|R_PPC_ADDR24|R_PPC_ADDR16|R_PPC_ADDR16_LO|R_PPC_ADDR16_HI|R_PPC_ADDR16_HA|R_PPC_ADDR14|R_PPC_ADDR14_BRTAKEN|R_PPC_ADDR14_BRNTAKEN
+include $(srctree)/lib/vdso/Makefile
+
 obj-vdso64 = sigtramp.o gettimeofday.o datapage.o cacheflush.o note.o getcpu.o
 
+ifneq ($(c-gettimeofday-y),)
+  CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
+  CFLAGS_vgettimeofday.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
+  CFLAGS_vgettimeofday.o += $(call cc-option, -fno-stack-protector)
+  CFLAGS_vgettimeofday.o += -DDISABLE_BRANCH_PROFILING
+  CFLAGS_vgettimeofday.o += -ffreestanding -fasynchronous-unwind-tables
+  CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE)
+endif
+
 # Build rules
 
 targets := $(obj-vdso64) vdso64.so vdso64.so.dbg
@@ -11,6 +23,7 @@ obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
 GCOV_PROFILE := n
 KCOV_INSTRUMENT := n
 UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
 
 ccflags-y := -shared -fno-common -fno-builtin -nostdlib \
 	-Wl,-soname=linux-vdso64.so.1 -Wl,--hash-style=both
@@ -20,12 +33,14 @@ obj-y += vdso64_wrapper.o
 extra-y += vdso64.lds
 CPPFLAGS_vdso64.lds += -P -C -U$(ARCH)
 
+$(obj)/vgettimeofday.o: %.o: %.c FORCE
+
 # Force dependency (incbin is bad)
 $(obj)/vdso64_wrapper.o : $(obj)/vdso64.so
 
 # link rule for the .so file, .lds has to be first
-$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64) FORCE
-	$(call if_changed,vdso64ld)
+$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64) $(obj)/vgettimeofday.o FORCE
+	$(call if_changed,vdso64ld_and_check)
 
 # strip rule for the .so file
 $(obj)/%.so: OBJCOPYFLAGS := -S
@@ -33,8 +48,8 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
 	$(call if_changed,objcopy)
 
 # actual build commands
-quiet_cmd_vdso64ld = VDSO64L $@
-      cmd_vdso64ld = $(CC) $(c_flags) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn)
+quiet_cmd_vdso64ld_and_check = VDSO64L $@
+      cmd_vdso64ld_and_check = $(CC) $(c_flags) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn); $(cmd_vdso_check)
 
 # install commands for the unstripped file
 quiet_cmd_vdso_install = INSTALL $@
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
index 20f8be40c653..d7a7bfb51081 100644
--- a/arch/powerpc/kernel/vdso64/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
@@ -12,6 +12,7 @@
 #include <asm/vdso_datapage.h>
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
+#include <asm/vdso/gettimeofday.h>
 
 	.text
 /*
@@ -21,31 +22,7 @@
  *
  */
 V_FUNCTION_BEGIN(__kernel_gettimeofday)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr	r11,r3			/* r11 holds tv */
-	mr	r10,r4			/* r10 holds tz */
-	get_datapage	r3, r0
-	cmpldi	r11,0			/* check if tv is NULL */
-	beq	2f
-	lis	r7,1000000@ha		/* load up USEC_PER_SEC */
-	addi	r7,r7,1000000@l
-	bl	V_LOCAL_FUNC(__do_get_tspec) /* get sec/us from tb & kernel */
-	std	r4,TVAL64_TV_SEC(r11)	/* store sec in tv */
-	std	r5,TVAL64_TV_USEC(r11)	/* store usec in tv */
-2:	cmpldi	r10,0			/* check if tz is NULL */
-	beq	1f
-	lwz	r4,CFG_TZ_MINUTEWEST(r3)/* fill tz */
-	lwz	r5,CFG_TZ_DSTTIME(r3)
-	stw	r4,TZONE_TZ_MINWEST(r10)
-	stw	r5,TZONE_TZ_DSTTIME(r10)
-1:	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0			/* always success */
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_gettimeofday
 V_FUNCTION_END(__kernel_gettimeofday)
 
 
@@ -56,120 +33,7 @@ V_FUNCTION_END(__kernel_gettimeofday)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_gettime)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmpwi	cr0,r3,CLOCK_REALTIME
-	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
-
-	cmpwi	cr5,r3,CLOCK_REALTIME_COARSE
-	cmpwi	cr6,r3,CLOCK_MONOTONIC_COARSE
-	cror	cr5*4+eq,cr5*4+eq,cr6*4+eq
-
-	cror	cr0*4+eq,cr0*4+eq,cr5*4+eq
-	bne	cr0,99f
-
-	mflr	r12			/* r12 saves lr */
-  .cfi_register lr,r12
-	mr	r11,r4			/* r11 saves tp */
-	get_datapage	r3, r0
-	lis	r7,NSEC_PER_SEC@h	/* want nanoseconds */
-	ori	r7,r7,NSEC_PER_SEC@l
-	beq	cr5,70f
-50:	bl	V_LOCAL_FUNC(__do_get_tspec)	/* get time from tb & kernel */
-	bne	cr1,80f			/* if not monotonic, all done */
-
-	/*
-	 * CLOCK_MONOTONIC
-	 */
-
-	/* now we must fixup using wall to monotonic. We need to snapshot
-	 * that value and do the counter trick again. Fortunately, we still
-	 * have the counter value in r8 that was returned by __do_get_tspec.
-	 * At this point, r4,r5 contain our sec/nsec values.
-	 */
-
-	ld	r6,WTOM_CLOCK_SEC(r3)
-	lwa	r9,WTOM_CLOCK_NSEC(r3)
-
-	/* We now have our result in r6,r9. We create a fake dependency
-	 * on that result and re-check the counter
-	 */
-	or	r0,r6,r9
-	xor	r0,r0,r0
-	add	r3,r3,r0
-	ld	r0,CFG_TB_UPDATE_COUNT(r3)
-        cmpld   cr0,r0,r8		/* check if updated */
-	bne-	50b
-	b	78f
-
-	/*
-	 * For coarse clocks we get data directly from the vdso data page, so
-	 * we don't need to call __do_get_tspec, but we still need to do the
-	 * counter trick.
-	 */
-70:	ld      r8,CFG_TB_UPDATE_COUNT(r3)
-	andi.   r0,r8,1                 /* pending update ? loop */
-	bne-    70b
-	add     r3,r3,r0		/* r0 is already 0 */
-
-	/*
-	 * CLOCK_REALTIME_COARSE, below values are needed for MONOTONIC_COARSE
-	 * too
-	 */
-	ld      r4,STAMP_XTIME_SEC(r3)
-	ld      r5,STAMP_XTIME_NSEC(r3)
-	bne     cr6,75f
-
-	/* CLOCK_MONOTONIC_COARSE */
-	ld	r6,WTOM_CLOCK_SEC(r3)
-	lwa     r9,WTOM_CLOCK_NSEC(r3)
-
-	/* check if counter has updated */
-	or      r0,r6,r9
-75:	or	r0,r0,r4
-	or	r0,r0,r5
-	xor     r0,r0,r0
-	add     r3,r3,r0
-	ld      r0,CFG_TB_UPDATE_COUNT(r3)
-	cmpld   cr0,r0,r8               /* check if updated */
-	bne-    70b
-
-	/* Counter has not updated, so continue calculating proper values for
-	 * sec and nsec if monotonic coarse, or just return with the proper
-	 * values for realtime.
-	 */
-	bne     cr6,80f
-
-	/* Add wall->monotonic offset and check for overflow or underflow */
-78:	add     r4,r4,r6
-	add     r5,r5,r9
-	cmpd    cr0,r5,r7
-	cmpdi   cr1,r5,0
-	blt     79f
-	subf    r5,r7,r5
-	addi    r4,r4,1
-79:	bge     cr1,80f
-	addi    r4,r4,-1
-	add     r5,r5,r7
-
-80:	std	r4,TSPC64_TV_SEC(r11)
-	std	r5,TSPC64_TV_NSEC(r11)
-
-	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-99:
-	li	r0,__NR_clock_gettime
-  .cfi_restore lr
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
 
@@ -180,34 +44,7 @@ V_FUNCTION_END(__kernel_clock_gettime)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_getres)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmpwi	cr0,r3,CLOCK_REALTIME
-	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
-	bne	cr0,99f
-
-	mflr	r12
-  .cfi_register lr,r12
-	get_datapage	r3, r0
-	lwz	r5, CLOCK_HRTIMER_RES(r3)
-	mtlr	r12
-	li	r3,0
-	cmpldi	cr0,r4,0
-	crclr	cr0*4+so
-	beqlr
-	std	r3,TSPC64_TV_SEC(r4)
-	std	r5,TSPC64_TV_NSEC(r4)
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-99:
-	li	r0,__NR_clock_getres
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_getres
 V_FUNCTION_END(__kernel_clock_getres)
 
 /*
@@ -217,74 +54,5 @@ V_FUNCTION_END(__kernel_clock_getres)
  *
  */
 V_FUNCTION_BEGIN(__kernel_time)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr	r11,r3			/* r11 holds t */
-	get_datapage	r3, r0
-
-	ld	r4,STAMP_XTIME_SEC(r3)
-
-	cmpldi	r11,0			/* check if t is NULL */
-	beq	2f
-	std	r4,0(r11)		/* store result at *t */
-2:	mtlr	r12
-	crclr	cr0*4+so
-	mr	r3,r4
-	blr
-  .cfi_endproc
+	cvdso_call_time __c_kernel_time
 V_FUNCTION_END(__kernel_time)
-
-
-/*
- * This is the core of clock_gettime() and gettimeofday(),
- * it returns the current time in r4 (seconds) and r5.
- * On entry, r7 gives the resolution of r5, either USEC_PER_SEC
- * or NSEC_PER_SEC, giving r5 in microseconds or nanoseconds.
- * It expects the datapage ptr in r3 and doesn't clobber it.
- * It clobbers r0, r6 and r9.
- * On return, r8 contains the counter value that can be reused.
- * This clobbers cr0 but not any other cr field.
- */
-V_FUNCTION_BEGIN(__do_get_tspec)
-  .cfi_startproc
-	/* check for update count & load values */
-1:	ld	r8,CFG_TB_UPDATE_COUNT(r3)
-	andi.	r0,r8,1			/* pending update ? loop */
-	bne-	1b
-	xor	r0,r8,r8		/* create dependency */
-	add	r3,r3,r0
-
-	/* Get TB & offset it. We use the MFTB macro which will generate
-	 * workaround code for Cell.
-	 */
-	MFTB(r6)
-	ld	r9,CFG_TB_ORIG_STAMP(r3)
-	subf	r6,r9,r6
-
-	/* Scale result */
-	ld	r5,CFG_TB_TO_XS(r3)
-	sldi	r6,r6,12		/* compute time since stamp_xtime */
-	mulhdu	r6,r6,r5		/* in units of 2^-32 seconds */
-
-	/* Add stamp since epoch */
-	ld	r4,STAMP_XTIME_SEC(r3)
-	lwz	r5,STAMP_SEC_FRAC(r3)
-	or	r0,r4,r5
-	or	r0,r0,r6
-	xor	r0,r0,r0
-	add	r3,r3,r0
-	ld	r0,CFG_TB_UPDATE_COUNT(r3)
-	cmpld   r0,r8			/* check if updated */
-	bne-	1b			/* reload if so */
-
-	/* convert to seconds & nanoseconds and add to stamp */
-	add	r6,r6,r5		/* add on fractional seconds of xtime */
-	mulhwu	r5,r6,r7		/* compute micro or nanoseconds and */
-	srdi	r6,r6,32		/* seconds since stamp_xtime */
-	clrldi	r5,r5,32
-	add	r4,r4,r6
-	blr
-  .cfi_endproc
-V_FUNCTION_END(__do_get_tspec)
-- 
2.25.0




^ permalink raw reply related

* [PATCH v10 5/5] powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32
From: Christophe Leroy @ 2020-08-05  7:09 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl,
	anton
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev
In-Reply-To: <cover.1596611196.git.christophe.leroy@csgroup.eu>

Provides __kernel_clock_gettime64() on vdso32. This is the
64 bits version of __kernel_clock_gettime() which is
y2038 compliant.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/vdso32/gettimeofday.S  | 9 +++++++++
 arch/powerpc/kernel/vdso32/vdso32.lds.S    | 1 +
 arch/powerpc/kernel/vdso32/vgettimeofday.c | 6 ++++++
 3 files changed, 16 insertions(+)

diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
index fd7b01c51281..a6e29f880e0e 100644
--- a/arch/powerpc/kernel/vdso32/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
@@ -35,6 +35,15 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
 	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
+/*
+ * Exact prototype of clock_gettime64()
+ *
+ * int __kernel_clock_gettime64(clockid_t clock_id, struct __timespec64 *ts);
+ *
+ */
+V_FUNCTION_BEGIN(__kernel_clock_gettime64)
+	cvdso_call __c_kernel_clock_gettime64
+V_FUNCTION_END(__kernel_clock_gettime64)
 
 /*
  * Exact prototype of clock_getres()
diff --git a/arch/powerpc/kernel/vdso32/vdso32.lds.S b/arch/powerpc/kernel/vdso32/vdso32.lds.S
index 4c985467a668..582c5b046cc9 100644
--- a/arch/powerpc/kernel/vdso32/vdso32.lds.S
+++ b/arch/powerpc/kernel/vdso32/vdso32.lds.S
@@ -148,6 +148,7 @@ VERSION
 #ifndef CONFIG_PPC_BOOK3S_601
 		__kernel_gettimeofday;
 		__kernel_clock_gettime;
+		__kernel_clock_gettime64;
 		__kernel_clock_getres;
 		__kernel_time;
 		__kernel_get_tbfreq;
diff --git a/arch/powerpc/kernel/vdso32/vgettimeofday.c b/arch/powerpc/kernel/vdso32/vgettimeofday.c
index 0b9ab4c22ef2..f7f71fecf4ed 100644
--- a/arch/powerpc/kernel/vdso32/vgettimeofday.c
+++ b/arch/powerpc/kernel/vdso32/vgettimeofday.c
@@ -11,6 +11,12 @@ int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
 	return __cvdso_clock_gettime32_data(vd, clock, ts);
 }
 
+int __c_kernel_clock_gettime64(clockid_t clock, struct __kernel_timespec *ts,
+			       const struct vdso_data *vd)
+{
+	return __cvdso_clock_gettime_data(vd, clock, ts);
+}
+
 int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
 			    const struct vdso_data *vd)
 {
-- 
2.25.0


^ permalink raw reply related

* [PATCH v10 1/5] powerpc/processor: Move cpu_relax() into asm/vdso/processor.h
From: Christophe Leroy @ 2020-08-05  7:09 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl,
	anton
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev
In-Reply-To: <cover.1596611196.git.christophe.leroy@csgroup.eu>

cpu_relax() need to be in asm/vdso/processor.h to be used by
the C VDSO generic library.

Move it there.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9: Forgot to remove cpu_relax() from processor.h in v8
---
 arch/powerpc/include/asm/processor.h      | 13 ++-----------
 arch/powerpc/include/asm/vdso/processor.h | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+), 11 deletions(-)
 create mode 100644 arch/powerpc/include/asm/vdso/processor.h

diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index ed0d633ab5aa..c1ba9c8d9b90 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -6,6 +6,8 @@
  * Copyright (C) 2001 PPC 64 Team, IBM Corp
  */
 
+#include <vdso/processor.h>
+
 #include <asm/reg.h>
 
 #ifdef CONFIG_VSX
@@ -63,14 +65,6 @@ extern int _chrp_type;
 
 #endif /* defined(__KERNEL__) && defined(CONFIG_PPC32) */
 
-/* Macros for adjusting thread priority (hardware multi-threading) */
-#define HMT_very_low()   asm volatile("or 31,31,31   # very low priority")
-#define HMT_low()	 asm volatile("or 1,1,1	     # low priority")
-#define HMT_medium_low() asm volatile("or 6,6,6      # medium low priority")
-#define HMT_medium()	 asm volatile("or 2,2,2	     # medium priority")
-#define HMT_medium_high() asm volatile("or 5,5,5      # medium high priority")
-#define HMT_high()	 asm volatile("or 3,3,3	     # high priority")
-
 #ifdef __KERNEL__
 
 #ifdef CONFIG_PPC64
@@ -350,7 +344,6 @@ static inline unsigned long __pack_fe01(unsigned int fpmode)
 }
 
 #ifdef CONFIG_PPC64
-#define cpu_relax()	do { HMT_low(); HMT_medium(); barrier(); } while (0)
 
 #define spin_begin()	HMT_low()
 
@@ -369,8 +362,6 @@ do {								\
 	}							\
 } while (0)
 
-#else
-#define cpu_relax()	barrier()
 #endif
 
 /* Check that a certain kernel stack pointer is valid in task_struct p */
diff --git a/arch/powerpc/include/asm/vdso/processor.h b/arch/powerpc/include/asm/vdso/processor.h
new file mode 100644
index 000000000000..39b9beace9ca
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/processor.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __ASM_VDSO_PROCESSOR_H
+#define __ASM_VDSO_PROCESSOR_H
+
+#ifndef __ASSEMBLY__
+
+/* Macros for adjusting thread priority (hardware multi-threading) */
+#define HMT_very_low()		asm volatile("or 31, 31, 31	# very low priority")
+#define HMT_low()		asm volatile("or 1, 1, 1	# low priority")
+#define HMT_medium_low()	asm volatile("or 6, 6, 6	# medium low priority")
+#define HMT_medium()		asm volatile("or 2, 2, 2	# medium priority")
+#define HMT_medium_high()	asm volatile("or 5, 5, 5	# medium high priority")
+#define HMT_high()		asm volatile("or 3, 3, 3	# high priority")
+
+#ifdef CONFIG_PPC64
+#define cpu_relax()	do { HMT_low(); HMT_medium(); barrier(); } while (0)
+#else
+#define cpu_relax()	barrier()
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_PROCESSOR_H */
-- 
2.25.0


^ permalink raw reply related

* [PATCH v10 0/5] powerpc: switch VDSO to C implementation
From: Christophe Leroy @ 2020-08-05  7:09 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl,
	anton
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev

This is the tenth version of a series to switch powerpc VDSO to
generic C implementation.

Changes since v10 are:
- Added a comment explaining the reason for the double stack frame
- Moved back .cfi_register lr next to mflr

Main changes since v9 are:
- Dropped the patches which put the VDSO datapage in front of VDSO text in the mapping
- Adds a second stack frame because the caller doesn't set one, at least on PPC64
- Saving the TOC pointer on PPC64 (is that really needed ?)

This series applies on today's powerpc/merge branch.

See the last patches for details on changes and performance.

Christophe Leroy (5):
  powerpc/processor: Move cpu_relax() into asm/vdso/processor.h
  powerpc/vdso: Prepare for switching VDSO to generic C implementation.
  powerpc/vdso: Save and restore TOC pointer on PPC64
  powerpc/vdso: Switch VDSO to generic C implementation.
  powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32

 arch/powerpc/Kconfig                         |   2 +
 arch/powerpc/include/asm/clocksource.h       |   7 +
 arch/powerpc/include/asm/processor.h         |  13 +-
 arch/powerpc/include/asm/vdso/clocksource.h  |   7 +
 arch/powerpc/include/asm/vdso/gettimeofday.h | 197 ++++++++++++
 arch/powerpc/include/asm/vdso/processor.h    |  23 ++
 arch/powerpc/include/asm/vdso/vsyscall.h     |  25 ++
 arch/powerpc/include/asm/vdso_datapage.h     |  40 +--
 arch/powerpc/kernel/asm-offsets.c            |  49 +--
 arch/powerpc/kernel/time.c                   |  91 +-----
 arch/powerpc/kernel/vdso.c                   |   5 +-
 arch/powerpc/kernel/vdso32/Makefile          |  32 +-
 arch/powerpc/kernel/vdso32/config-fake32.h   |  34 +++
 arch/powerpc/kernel/vdso32/gettimeofday.S    | 300 +------------------
 arch/powerpc/kernel/vdso32/vdso32.lds.S      |   1 +
 arch/powerpc/kernel/vdso32/vgettimeofday.c   |  35 +++
 arch/powerpc/kernel/vdso64/Makefile          |  23 +-
 arch/powerpc/kernel/vdso64/gettimeofday.S    | 242 +--------------
 arch/powerpc/kernel/vdso64/vgettimeofday.c   |  29 ++
 19 files changed, 453 insertions(+), 702 deletions(-)
 create mode 100644 arch/powerpc/include/asm/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/gettimeofday.h
 create mode 100644 arch/powerpc/include/asm/vdso/processor.h
 create mode 100644 arch/powerpc/include/asm/vdso/vsyscall.h
 create mode 100644 arch/powerpc/kernel/vdso32/config-fake32.h
 create mode 100644 arch/powerpc/kernel/vdso32/vgettimeofday.c
 create mode 100644 arch/powerpc/kernel/vdso64/vgettimeofday.c

-- 
2.25.0


^ permalink raw reply

* [PATCH v10 3/5] powerpc/vdso: Save and restore TOC pointer on PPC64
From: Christophe Leroy @ 2020-08-05  7:09 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl,
	anton
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev
In-Reply-To: <cover.1596611196.git.christophe.leroy@csgroup.eu>

On PPC64, the TOC pointer needs to be saved and restored.

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9: New.

I'm not sure this is really needed, I can't see the VDSO C code doing
anything with r2, at least on ppc64_defconfig.

So I let you decide whether you take it or not.
---
 arch/powerpc/include/asm/vdso/gettimeofday.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
index e2c462796a22..8ed4329c9fb8 100644
--- a/arch/powerpc/include/asm/vdso/gettimeofday.h
+++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
@@ -19,10 +19,16 @@
   .cfi_register lr, r0
 	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
 	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	get_datapage	r5, r0
 	addi		r5, r5, VDSO_DATA_OFFSET
 	bl		\funct
 	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_LL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	cmpwi		r3, 0
 	mtlr		r0
   .cfi_restore lr
@@ -42,10 +48,16 @@
   .cfi_register lr, r0
 	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
 	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	get_datapage	r4, r0
 	addi		r4, r4, VDSO_DATA_OFFSET
 	bl		\funct
 	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_LL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	crclr		so
 	mtlr		r0
   .cfi_restore lr
-- 
2.25.0


^ permalink raw reply related

* Re: [PATCH v3 3/3] ASoC: fsl_sai: Replace synchronous check with fsl_sai_dir_is_synced
From: Nicolin Chen @ 2020-08-05  6:55 UTC (permalink / raw)
  To: Shengjiu Wang
  Cc: alsa-devel, timur, Xiubo.Lee, linuxppc-dev, tiwai, lgirdwood,
	perex, broonie, festevam, linux-kernel
In-Reply-To: <20200805063413.4610-4-shengjiu.wang@nxp.com>

On Wed, Aug 05, 2020 at 02:34:13PM +0800, Shengjiu Wang wrote:
> As new function fsl_sai_dir_is_synced is included for checking if
> stream is synced by the opposite stream, then replace the existing
> synchronous checking with this new function.
> 
> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>

Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>

Nice, thanks!

^ permalink raw reply

* [PATCH v3 3/3] ASoC: fsl_sai: Replace synchronous check with fsl_sai_dir_is_synced
From: Shengjiu Wang @ 2020-08-05  6:34 UTC (permalink / raw)
  To: timur, nicoleotsuka, Xiubo.Lee, festevam, lgirdwood, broonie,
	perex, tiwai, alsa-devel, linuxppc-dev, linux-kernel
In-Reply-To: <20200805063413.4610-1-shengjiu.wang@nxp.com>

As new function fsl_sai_dir_is_synced is included for checking if
stream is synced by the opposite stream, then replace the existing
synchronous checking with this new function.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
---
 sound/soc/fsl/fsl_sai.c | 40 ++++++++++++++++------------------------
 1 file changed, 16 insertions(+), 24 deletions(-)

diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c
index 334090d581ae..f6969a5d49e3 100644
--- a/sound/soc/fsl/fsl_sai.c
+++ b/sound/soc/fsl/fsl_sai.c
@@ -350,6 +350,8 @@ static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq)
 	unsigned int ofs = sai->soc_data->reg_offset;
 	unsigned long clk_rate;
 	u32 savediv = 0, ratio, savesub = freq;
+	int adir = tx ? RX : TX;
+	int dir = tx ? TX : RX;
 	u32 id;
 	int ret = 0;
 
@@ -408,19 +410,17 @@ static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq)
 	 * 4) For Tx and Rx are both Synchronous with another SAI, we just
 	 *    ignore it.
 	 */
-	if ((sai->synchronous[TX] && !sai->synchronous[RX]) ||
-	    (!tx && !sai->synchronous[RX])) {
-		regmap_update_bits(sai->regmap, FSL_SAI_RCR2(ofs),
+	if (fsl_sai_dir_is_synced(sai, adir)) {
+		regmap_update_bits(sai->regmap, FSL_SAI_xCR2(!tx, ofs),
 				   FSL_SAI_CR2_MSEL_MASK,
 				   FSL_SAI_CR2_MSEL(sai->mclk_id[tx]));
-		regmap_update_bits(sai->regmap, FSL_SAI_RCR2(ofs),
+		regmap_update_bits(sai->regmap, FSL_SAI_xCR2(!tx, ofs),
 				   FSL_SAI_CR2_DIV_MASK, savediv - 1);
-	} else if ((sai->synchronous[RX] && !sai->synchronous[TX]) ||
-		   (tx && !sai->synchronous[TX])) {
-		regmap_update_bits(sai->regmap, FSL_SAI_TCR2(ofs),
+	} else if (!sai->synchronous[dir]) {
+		regmap_update_bits(sai->regmap, FSL_SAI_xCR2(tx, ofs),
 				   FSL_SAI_CR2_MSEL_MASK,
 				   FSL_SAI_CR2_MSEL(sai->mclk_id[tx]));
-		regmap_update_bits(sai->regmap, FSL_SAI_TCR2(ofs),
+		regmap_update_bits(sai->regmap, FSL_SAI_xCR2(tx, ofs),
 				   FSL_SAI_CR2_DIV_MASK, savediv - 1);
 	}
 
@@ -442,6 +442,7 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
 	u32 val_cr4 = 0, val_cr5 = 0;
 	u32 slots = (channels == 1) ? 2 : channels;
 	u32 slot_width = word_width;
+	int adir = tx ? RX : TX;
 	int ret;
 
 	if (sai->slots)
@@ -491,22 +492,13 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
 	 * RCR5(TCR5) for playback(capture), or there will be sync error.
 	 */
 
-	if (!sai->is_slave_mode) {
-		if (!sai->synchronous[TX] && sai->synchronous[RX] && !tx) {
-			regmap_update_bits(sai->regmap, FSL_SAI_TCR4(ofs),
-				FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
-				val_cr4);
-			regmap_update_bits(sai->regmap, FSL_SAI_TCR5(ofs),
-				FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
-				FSL_SAI_CR5_FBT_MASK, val_cr5);
-		} else if (!sai->synchronous[RX] && sai->synchronous[TX] && tx) {
-			regmap_update_bits(sai->regmap, FSL_SAI_RCR4(ofs),
-				FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
-				val_cr4);
-			regmap_update_bits(sai->regmap, FSL_SAI_RCR5(ofs),
-				FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
-				FSL_SAI_CR5_FBT_MASK, val_cr5);
-		}
+	if (!sai->is_slave_mode && fsl_sai_dir_is_synced(sai, adir)) {
+		regmap_update_bits(sai->regmap, FSL_SAI_xCR4(!tx, ofs),
+				   FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
+				   val_cr4);
+		regmap_update_bits(sai->regmap, FSL_SAI_xCR5(!tx, ofs),
+				   FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
+				   FSL_SAI_CR5_FBT_MASK, val_cr5);
 	}
 
 	regmap_update_bits(sai->regmap, FSL_SAI_xCR4(tx, ofs),
-- 
2.27.0


^ permalink raw reply related

* [PATCH v3 2/3] ASoC: fsl_sai: Drop TMR/RMR settings for synchronous mode
From: Shengjiu Wang @ 2020-08-05  6:34 UTC (permalink / raw)
  To: timur, nicoleotsuka, Xiubo.Lee, festevam, lgirdwood, broonie,
	perex, tiwai, alsa-devel, linuxppc-dev, linux-kernel
In-Reply-To: <20200805063413.4610-1-shengjiu.wang@nxp.com>

Tx synchronous with Rx: The RMR is the word mask register, it is used
to mask any word in the frame, it is not relating to clock generation,
So it is no need to be changed when Tx is going to be enabled.

Rx synchronous with Tx: The TMR is the word mask register, it is used
to mask any word in the frame, it is not relating to clock generation,
So it is no need to be changed when Rx is going to be enabled.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
---
 sound/soc/fsl/fsl_sai.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c
index 566c4747362a..334090d581ae 100644
--- a/sound/soc/fsl/fsl_sai.c
+++ b/sound/soc/fsl/fsl_sai.c
@@ -488,8 +488,7 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
 	/*
 	 * For SAI master mode, when Tx(Rx) sync with Rx(Tx) clock, Rx(Tx) will
 	 * generate bclk and frame clock for Tx(Rx), we should set RCR4(TCR4),
-	 * RCR5(TCR5) and RMR(TMR) for playback(capture), or there will be sync
-	 * error.
+	 * RCR5(TCR5) for playback(capture), or there will be sync error.
 	 */
 
 	if (!sai->is_slave_mode) {
@@ -500,8 +499,6 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
 			regmap_update_bits(sai->regmap, FSL_SAI_TCR5(ofs),
 				FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
 				FSL_SAI_CR5_FBT_MASK, val_cr5);
-			regmap_write(sai->regmap, FSL_SAI_TMR,
-				~0UL - ((1 << channels) - 1));
 		} else if (!sai->synchronous[RX] && sai->synchronous[TX] && tx) {
 			regmap_update_bits(sai->regmap, FSL_SAI_RCR4(ofs),
 				FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
@@ -509,8 +506,6 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
 			regmap_update_bits(sai->regmap, FSL_SAI_RCR5(ofs),
 				FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
 				FSL_SAI_CR5_FBT_MASK, val_cr5);
-			regmap_write(sai->regmap, FSL_SAI_RMR,
-				~0UL - ((1 << channels) - 1));
 		}
 	}
 
-- 
2.27.0


^ permalink raw reply related

* [PATCH v3 1/3] ASoC: fsl_sai: Refine enable/disable TE/RE sequence in trigger()
From: Shengjiu Wang @ 2020-08-05  6:34 UTC (permalink / raw)
  To: timur, nicoleotsuka, Xiubo.Lee, festevam, lgirdwood, broonie,
	perex, tiwai, alsa-devel, linuxppc-dev, linux-kernel
In-Reply-To: <20200805063413.4610-1-shengjiu.wang@nxp.com>

Current code enables TCSR.TE and RCSR.RE together, and disable
TCSR.TE and RCSR.RE together in trigger(), which only supports
one operation mode:
1. Rx synchronous with Tx: TE is last enabled and first disabled

Other operation mode need to be considered also:
2. Tx synchronous with Rx: RE is last enabled and first disabled.
3. Asynchronous mode: Tx and Rx are independent.

So the enable TCSR.TE and RCSR.RE sequence and the disable
sequence need to be refined accordingly for #2 and #3.

There is slightly against what RM recommennds with this change.
For example in Rx synchronous with Tx mode, case "aplay 1.wav;
arecord 2.wav" enable TE before RE. But it should be safe to
do so, judging by years of testing results.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
---
 sound/soc/fsl/fsl_sai.c | 126 +++++++++++++++++++++++++++-------------
 1 file changed, 85 insertions(+), 41 deletions(-)

diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c
index cdff739924e2..566c4747362a 100644
--- a/sound/soc/fsl/fsl_sai.c
+++ b/sound/soc/fsl/fsl_sai.c
@@ -37,6 +37,24 @@ static const struct snd_pcm_hw_constraint_list fsl_sai_rate_constraints = {
 	.list = fsl_sai_rates,
 };
 
+/**
+ * fsl_sai_dir_is_synced - Check if stream is synced by the opposite stream
+ *
+ * SAI supports synchronous mode using bit/frame clocks of either Transmitter's
+ * or Receiver's for both streams. This function is used to check if clocks of
+ * the stream's are synced by the opposite stream.
+ *
+ * @sai: SAI context
+ * @dir: stream direction
+ */
+static inline bool fsl_sai_dir_is_synced(struct fsl_sai *sai, int dir)
+{
+	int adir = (dir == TX) ? RX : TX;
+
+	/* current dir in async mode while opposite dir in sync mode */
+	return !sai->synchronous[dir] && sai->synchronous[adir];
+}
+
 static irqreturn_t fsl_sai_isr(int irq, void *devid)
 {
 	struct fsl_sai *sai = (struct fsl_sai *)devid;
@@ -522,6 +540,38 @@ static int fsl_sai_hw_free(struct snd_pcm_substream *substream,
 	return 0;
 }
 
+static void fsl_sai_config_disable(struct fsl_sai *sai, int dir)
+{
+	unsigned int ofs = sai->soc_data->reg_offset;
+	bool tx = dir == TX;
+	u32 xcsr, count = 100;
+
+	regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx, ofs),
+			   FSL_SAI_CSR_TERE, 0);
+
+	/* TERE will remain set till the end of current frame */
+	do {
+		udelay(10);
+		regmap_read(sai->regmap, FSL_SAI_xCSR(tx, ofs), &xcsr);
+	} while (--count && xcsr & FSL_SAI_CSR_TERE);
+
+	regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx, ofs),
+			   FSL_SAI_CSR_FR, FSL_SAI_CSR_FR);
+
+	/*
+	 * For sai master mode, after several open/close sai,
+	 * there will be no frame clock, and can't recover
+	 * anymore. Add software reset to fix this issue.
+	 * This is a hardware bug, and will be fix in the
+	 * next sai version.
+	 */
+	if (!sai->is_slave_mode) {
+		/* Software Reset */
+		regmap_write(sai->regmap, FSL_SAI_xCSR(tx, ofs), FSL_SAI_CSR_SR);
+		/* Clear SR bit to finish the reset */
+		regmap_write(sai->regmap, FSL_SAI_xCSR(tx, ofs), 0);
+	}
+}
 
 static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
 		struct snd_soc_dai *cpu_dai)
@@ -530,7 +580,9 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
 	unsigned int ofs = sai->soc_data->reg_offset;
 
 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
-	u32 xcsr, count = 100;
+	int adir = tx ? RX : TX;
+	int dir = tx ? TX : RX;
+	u32 xcsr;
 
 	/*
 	 * Asynchronous mode: Clear SYNC for both Tx and Rx.
@@ -553,10 +605,22 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx, ofs),
 				   FSL_SAI_CSR_FRDE, FSL_SAI_CSR_FRDE);
 
-		regmap_update_bits(sai->regmap, FSL_SAI_RCSR(ofs),
-				   FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
-		regmap_update_bits(sai->regmap, FSL_SAI_TCSR(ofs),
+		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx, ofs),
 				   FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
+		/*
+		 * Enable the opposite direction for synchronous mode
+		 * 1. Tx sync with Rx: only set RE for Rx; set TE & RE for Tx
+		 * 2. Rx sync with Tx: only set TE for Tx; set RE & TE for Rx
+		 *
+		 * RM recommends to enable RE after TE for case 1 and to enable
+		 * TE after RE for case 2, but we here may not always guarantee
+		 * that happens: "arecord 1.wav; aplay 2.wav" in case 1 enables
+		 * TE after RE, which is against what RM recommends but should
+		 * be safe to do, judging by years of testing results.
+		 */
+		if (fsl_sai_dir_is_synced(sai, adir))
+			regmap_update_bits(sai->regmap, FSL_SAI_xCSR((!tx), ofs),
+					   FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
 
 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx, ofs),
 				   FSL_SAI_CSR_xIE_MASK, FSL_SAI_FLAGS);
@@ -571,43 +635,23 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
 
 		/* Check if the opposite FRDE is also disabled */
 		regmap_read(sai->regmap, FSL_SAI_xCSR(!tx, ofs), &xcsr);
-		if (!(xcsr & FSL_SAI_CSR_FRDE)) {
-			/* Disable both directions and reset their FIFOs */
-			regmap_update_bits(sai->regmap, FSL_SAI_TCSR(ofs),
-					   FSL_SAI_CSR_TERE, 0);
-			regmap_update_bits(sai->regmap, FSL_SAI_RCSR(ofs),
-					   FSL_SAI_CSR_TERE, 0);
-
-			/* TERE will remain set till the end of current frame */
-			do {
-				udelay(10);
-				regmap_read(sai->regmap,
-					    FSL_SAI_xCSR(tx, ofs), &xcsr);
-			} while (--count && xcsr & FSL_SAI_CSR_TERE);
-
-			regmap_update_bits(sai->regmap, FSL_SAI_TCSR(ofs),
-					   FSL_SAI_CSR_FR, FSL_SAI_CSR_FR);
-			regmap_update_bits(sai->regmap, FSL_SAI_RCSR(ofs),
-					   FSL_SAI_CSR_FR, FSL_SAI_CSR_FR);
-
-			/*
-			 * For sai master mode, after several open/close sai,
-			 * there will be no frame clock, and can't recover
-			 * anymore. Add software reset to fix this issue.
-			 * This is a hardware bug, and will be fix in the
-			 * next sai version.
-			 */
-			if (!sai->is_slave_mode) {
-				/* Software Reset for both Tx and Rx */
-				regmap_write(sai->regmap, FSL_SAI_TCSR(ofs),
-					     FSL_SAI_CSR_SR);
-				regmap_write(sai->regmap, FSL_SAI_RCSR(ofs),
-					     FSL_SAI_CSR_SR);
-				/* Clear SR bit to finish the reset */
-				regmap_write(sai->regmap, FSL_SAI_TCSR(ofs), 0);
-				regmap_write(sai->regmap, FSL_SAI_RCSR(ofs), 0);
-			}
-		}
+
+		/*
+		 * If opposite stream provides clocks for synchronous mode and
+		 * it is inactive, disable it before disabling the current one
+		 */
+		if (fsl_sai_dir_is_synced(sai, adir) && !(xcsr & FSL_SAI_CSR_FRDE))
+			fsl_sai_config_disable(sai, adir);
+
+		/*
+		 * Disable current stream if either of:
+		 * 1. current stream doesn't provide clocks for synchronous mode
+		 * 2. current stream provides clocks for synchronous mode but no
+		 *    more stream is active.
+		 */
+		if (!fsl_sai_dir_is_synced(sai, dir) || !(xcsr & FSL_SAI_CSR_FRDE))
+			fsl_sai_config_disable(sai, dir);
+
 		break;
 	default:
 		return -EINVAL;
-- 
2.27.0


^ permalink raw reply related

* [PATCH v3 0/3] refine and clean code for synchronous mode
From: Shengjiu Wang @ 2020-08-05  6:34 UTC (permalink / raw)
  To: timur, nicoleotsuka, Xiubo.Lee, festevam, lgirdwood, broonie,
	perex, tiwai, alsa-devel, linuxppc-dev, linux-kernel

refine and clean code for synchronous mode

Shengjiu Wang (3):
  ASoC: fsl_sai: Refine enable/disable TE/RE sequence in trigger()
  ASoC: fsl_sai: Drop TMR/RMR settings for synchronous mode
  ASoC: fsl_sai: Replace synchronous check with fsl_sai_dir_is_synced

changes in v3:
- Add reviewed-by Nicolin
- refine the commit log.
- Add one more patch #3

changes in v2:
- Split the commit
- refine the sequence in trigger stop

 sound/soc/fsl/fsl_sai.c | 173 +++++++++++++++++++++++-----------------
 1 file changed, 102 insertions(+), 71 deletions(-)

-- 
2.27.0


^ permalink raw reply

* [PATCH v3 2/2] powerpc/watchpoint/ptrace: Introduce PPC_DEBUG_FEATURE_DATA_BP_ARCH_31
From: Ravi Bangoria @ 2020-08-05  6:27 UTC (permalink / raw)
  To: mpe
  Cc: christophe.leroy, ravi.bangoria, mikey, rogealve, linux-kernel,
	paulus, jniethe5, pedromfc, naveen.n.rao, linuxppc-dev
In-Reply-To: <20200805062750.290289-1-ravi.bangoria@linux.ibm.com>

PPC_DEBUG_FEATURE_DATA_BP_ARCH_31 can be used to determine whether
we are running on an ISA 3.1 compliant machine. Which is needed to
determine DAR behaviour, 512 byte boundary limit etc. This was
requested by Pedro Miraglia Franco de Carvalho for extending
watchpoint features in gdb. Note that availability of 2nd DAWR is
independent of this flag and should be checked using
ppc_debug_info->num_data_bps.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
---
 Documentation/powerpc/ptrace.rst          | 1 +
 arch/powerpc/include/uapi/asm/ptrace.h    | 1 +
 arch/powerpc/kernel/ptrace/ptrace-noadv.c | 2 ++
 3 files changed, 4 insertions(+)

diff --git a/Documentation/powerpc/ptrace.rst b/Documentation/powerpc/ptrace.rst
index 864d4b6dddd1..77725d69eb4a 100644
--- a/Documentation/powerpc/ptrace.rst
+++ b/Documentation/powerpc/ptrace.rst
@@ -46,6 +46,7 @@ features will have bits indicating whether there is support for::
   #define PPC_DEBUG_FEATURE_DATA_BP_RANGE		0x4
   #define PPC_DEBUG_FEATURE_DATA_BP_MASK		0x8
   #define PPC_DEBUG_FEATURE_DATA_BP_DAWR		0x10
+  #define PPC_DEBUG_FEATURE_DATA_BP_ARCH_31		0x20
 
 2. PTRACE_SETHWDEBUG
 
diff --git a/arch/powerpc/include/uapi/asm/ptrace.h b/arch/powerpc/include/uapi/asm/ptrace.h
index f5f1ccc740fc..7004cfea3f5f 100644
--- a/arch/powerpc/include/uapi/asm/ptrace.h
+++ b/arch/powerpc/include/uapi/asm/ptrace.h
@@ -222,6 +222,7 @@ struct ppc_debug_info {
 #define PPC_DEBUG_FEATURE_DATA_BP_RANGE		0x0000000000000004
 #define PPC_DEBUG_FEATURE_DATA_BP_MASK		0x0000000000000008
 #define PPC_DEBUG_FEATURE_DATA_BP_DAWR		0x0000000000000010
+#define PPC_DEBUG_FEATURE_DATA_BP_ARCH_31	0x0000000000000020
 
 #ifndef __ASSEMBLY__
 
diff --git a/arch/powerpc/kernel/ptrace/ptrace-noadv.c b/arch/powerpc/kernel/ptrace/ptrace-noadv.c
index bf94ab837735..d5be73ab9e74 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-noadv.c
+++ b/arch/powerpc/kernel/ptrace/ptrace-noadv.c
@@ -57,6 +57,8 @@ void ppc_gethwdinfo(struct ppc_debug_info *dbginfo)
 	} else {
 		dbginfo->features = 0;
 	}
+	if (cpu_has_feature(CPU_FTR_ARCH_31))
+		dbginfo->features |= PPC_DEBUG_FEATURE_DATA_BP_ARCH_31;
 }
 
 int ptrace_get_debugreg(struct task_struct *child, unsigned long addr,
-- 
2.26.2


^ permalink raw reply related

* [PATCH v3 1/2] powerpc/watchpoint/ptrace: Fix SETHWDEBUG when CONFIG_HAVE_HW_BREAKPOINT=N
From: Ravi Bangoria @ 2020-08-05  6:27 UTC (permalink / raw)
  To: mpe
  Cc: christophe.leroy, ravi.bangoria, mikey, rogealve, linux-kernel,
	paulus, jniethe5, pedromfc, naveen.n.rao, linuxppc-dev
In-Reply-To: <20200805062750.290289-1-ravi.bangoria@linux.ibm.com>

When kernel is compiled with CONFIG_HAVE_HW_BREAKPOINT=N, user can
still create watchpoint using PPC_PTRACE_SETHWDEBUG, with limited
functionalities. But, such watchpoints are never firing because of
the missing privilege settings. Fix that.

Reported-by: Pedro Miraglia Franco de Carvalho <pedromfc@br.ibm.com>
Suggested-by: Pedro Miraglia Franco de Carvalho <pedromfc@br.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
---
 arch/powerpc/kernel/ptrace/ptrace-noadv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/ptrace/ptrace-noadv.c b/arch/powerpc/kernel/ptrace/ptrace-noadv.c
index 697c7e4b5877..bf94ab837735 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-noadv.c
+++ b/arch/powerpc/kernel/ptrace/ptrace-noadv.c
@@ -217,7 +217,7 @@ long ppc_set_hwdebug(struct task_struct *child, struct ppc_hw_breakpoint *bp_inf
 		return -EIO;
 
 	brk.address = ALIGN_DOWN(bp_info->addr, HW_BREAKPOINT_SIZE);
-	brk.type = HW_BRK_TYPE_TRANSLATE;
+	brk.type = HW_BRK_TYPE_TRANSLATE | HW_BRK_TYPE_USER;
 	brk.len = DABR_MAX_LEN;
 	if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_READ)
 		brk.type |= HW_BRK_TYPE_READ;
-- 
2.26.2


^ permalink raw reply related

* [PATCH v3 0/2] powerpc/watchpoint/ptrace: Buf fix plus new feature flag
From: Ravi Bangoria @ 2020-08-05  6:27 UTC (permalink / raw)
  To: mpe
  Cc: christophe.leroy, ravi.bangoria, mikey, rogealve, linux-kernel,
	paulus, jniethe5, pedromfc, naveen.n.rao, linuxppc-dev

Patch #1 fixes a bug when watchpoint is created with ptrace
PPC_PTRACE_SETHWDEBUG and CONFIG_HAVE_HW_BREAKPOINT=N.
patch #2 introduce new feature bit
PPC_DEBUG_FEATURE_DATA_BP_ARCH_31 which will be set when
running on ISA 3.1 compliant machine.

v2: https://lore.kernel.org/r/20200723093330.306341-1-ravi.bangoria@linux.ibm.com

v2->v3:
 - #1: is new
 - #2: Set PPC_DEBUG_FEATURE_DATA_BP_ARCH_31 unconditionally
   while running on p10.
 - Rebased to powerpc/next (cf1ae052e073)

Ravi Bangoria (2):
  powerpc/watchpoint/ptrace: Fix SETHWDEBUG when
    CONFIG_HAVE_HW_BREAKPOINT=N
  powerpc/watchpoint/ptrace: Introduce PPC_DEBUG_FEATURE_DATA_BP_ARCH_31

 Documentation/powerpc/ptrace.rst          | 1 +
 arch/powerpc/include/uapi/asm/ptrace.h    | 1 +
 arch/powerpc/kernel/ptrace/ptrace-noadv.c | 4 +++-
 3 files changed, 5 insertions(+), 1 deletion(-)

-- 
2.26.2


^ permalink raw reply

* Re: [PATCH v8 5/8] powerpc/vdso: Prepare for switching VDSO to generic C implementation.
From: Michael Ellerman @ 2020-08-05  6:24 UTC (permalink / raw)
  To: Christophe Leroy, Christophe Leroy, Benjamin Herrenschmidt,
	Paul Mackerras, nathanl
  Cc: linux-arch, arnd, linux-kernel, Tulio Magno Quites Machado Filho,
	luto, tglx, vincenzo.frascino, linuxppc-dev
In-Reply-To: <65fd7823-cc9d-c05a-0816-c34882b5d55a@csgroup.eu>

Christophe Leroy <christophe.leroy@csgroup.eu> writes:
> On 07/15/2020 01:04 AM, Michael Ellerman wrote:
>> Christophe Leroy <christophe.leroy@c-s.fr> writes:
>>> Prepare for switching VDSO to generic C implementation in following
>>> patch. Here, we:
>>> - Modify __get_datapage() to take an offset
>>> - Prepare the helpers to call the C VDSO functions
>>> - Prepare the required callbacks for the C VDSO functions
>>> - Prepare the clocksource.h files to define VDSO_ARCH_CLOCKMODES
>>> - Add the C trampolines to the generic C VDSO functions
>>>
>>> powerpc is a bit special for VDSO as well as system calls in the
>>> way that it requires setting CR SO bit which cannot be done in C.
>>> Therefore, entry/exit needs to be performed in ASM.
>>>
>>> Implementing __arch_get_vdso_data() would clobber the link register,
>>> requiring the caller to save it. As the ASM calling function already
>>> has to set a stack frame and saves the link register before calling
>>> the C vdso function, retriving the vdso data pointer there is lighter.
>> ...
>> 
>>> diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
>>> new file mode 100644
>>> index 000000000000..4452897f9bd8
>>> --- /dev/null
>>> +++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
>>> @@ -0,0 +1,175 @@
>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>> +#ifndef __ASM_VDSO_GETTIMEOFDAY_H
>>> +#define __ASM_VDSO_GETTIMEOFDAY_H
>>> +
>>> +#include <asm/ptrace.h>
>>> +
>>> +#ifdef __ASSEMBLY__
>>> +
>>> +.macro cvdso_call funct
>>> +  .cfi_startproc
>>> +	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
>>> +	mflr		r0
>>> +  .cfi_register lr, r0
>>> +	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
>> 
>> This doesn't work for me on ppc64(le) with glibc.
>> 
>> glibc doesn't create a stack frame before making the VDSO call, so the
>> store of r0 (LR) goes into the caller's frame, corrupting the saved LR,
>> leading to an infinite loop.
>> 
>> This is an example from a statically built program that calls
>> clock_gettime():
>> 
>> 0000000010030cb0 <__clock_gettime>:
>>      10030cb0:   0e 10 40 3c     lis     r2,4110
>>      10030cb4:   00 7a 42 38     addi    r2,r2,31232
>>      10030cb8:   a6 02 08 7c     mflr    r0
>>      10030cbc:   ff ff 22 3d     addis   r9,r2,-1
>>      10030cc0:   58 6d 29 39     addi    r9,r9,27992
>>      10030cc4:   f0 ff c1 fb     std     r30,-16(r1)			<-- redzone store
>>      10030cc8:   78 23 9e 7c     mr      r30,r4
>>      10030ccc:   f8 ff e1 fb     std     r31,-8(r1)			<-- redzone store
>>      10030cd0:   78 1b 7f 7c     mr      r31,r3
>>      10030cd4:   10 00 01 f8     std     r0,16(r1)			<-- save LR to caller's frame
>>      10030cd8:   00 00 09 e8     ld      r0,0(r9)
>>      10030cdc:   00 00 20 2c     cmpdi   r0,0
>>      10030ce0:   50 00 82 41     beq     10030d30 <__clock_gettime+0x80>
>>      10030ce4:   a6 03 09 7c     mtctr   r0
>>      10030ce8:   21 04 80 4e     bctrl					<-- vdso call
>>      10030cec:   26 00 00 7c     mfcr    r0
>>      10030cf0:   00 10 09 74     andis.  r9,r0,4096
>>      10030cf4:   78 1b 69 7c     mr      r9,r3
>>      10030cf8:   28 00 82 40     bne     10030d20 <__clock_gettime+0x70>
>>      10030cfc:   b4 07 23 7d     extsw   r3,r9
>>      10030d00:   10 00 01 e8     ld      r0,16(r1)			<-- load saved LR, since clobbered by the VDSO
>>      10030d04:   f0 ff c1 eb     ld      r30,-16(r1)
>>      10030d08:   f8 ff e1 eb     ld      r31,-8(r1)
>>      10030d0c:   a6 03 08 7c     mtlr    r0				<-- restore LR
>>      10030d10:   20 00 80 4e     blr					<-- jumps to 10030cec
>> 
>> 
>> I'm kind of confused how it worked for you on 32-bit.
>
> Indeed, 32-bit doesn't have a redzone, so I believe it needs a stack 
> frame whenever it has anything to same.

Yeah OK that would explain it.

> Here is what I have in libc.so:
>
> 000fbb60 <__clock_gettime>:
>     fbb60:	94 21 ff e0 	stwu    r1,-32(r1)
>     fbb64:	7c 08 02 a6 	mflr    r0
>     fbb68:	48 09 75 c9 	bl      193130 <_IO_stdout_+0x24b0>
>     fbb6c:	93 c1 00 18 	stw     r30,24(r1)
>     fbb70:	7f c8 02 a6 	mflr    r30
>     fbb74:	90 01 00 24 	stw     r0,36(r1)
>     fbb78:	93 81 00 10 	stw     r28,16(r1)
>     fbb7c:	93 a1 00 14 	stw     r29,20(r1)
>     fbb80:	83 9e fc 98 	lwz     r28,-872(r30)
>     fbb84:	93 e1 00 1c 	stw     r31,28(r1)
>     fbb88:	80 1c 00 00 	lwz     r0,0(r28)
>     fbb8c:	83 82 8f f4 	lwz     r28,-28684(r2)
>     fbb90:	7c 7f 1b 78 	mr      r31,r3
>     fbb94:	7c 00 e2 79 	xor.    r0,r0,r28
>     fbb98:	7c 9d 23 78 	mr      r29,r4
>     fbb9c:	41 82 00 40 	beq     fbbdc <__clock_gettime+0x7c>
>     fbba0:	7c 09 03 a6 	mtctr   r0
>     fbba4:	4e 80 04 21 	bctrl
>     fbba8:	7c 00 00 26 	mfcr    r0
>     fbbac:	74 1c 10 00 	andis.  r28,r0,4096
>     fbbb0:	40 82 00 24 	bne     fbbd4 <__clock_gettime+0x74>
>     fbbb4:	80 01 00 24 	lwz     r0,36(r1)
>     fbbb8:	83 81 00 10 	lwz     r28,16(r1)
>     fbbbc:	7c 08 03 a6 	mtlr    r0
>     fbbc0:	83 a1 00 14 	lwz     r29,20(r1)
>     fbbc4:	83 c1 00 18 	lwz     r30,24(r1)
>     fbbc8:	83 e1 00 1c 	lwz     r31,28(r1)
>     fbbcc:	38 21 00 20 	addi    r1,r1,32
>     fbbd0:	4e 80 00 20 	blr
> ...
>    193130:	4e 80 00 21 	blrl
>
> But I guess if a prog has a way to avoid having anything to save, we may 
> face the same issue.

Yes I think so.

> So lets create two frames:

Yeah I think that's what's required. Might need a comment explaining why
though ;)

> diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h 
> b/arch/powerpc/include/asm/vdso/gettimeofday.h
> index a0712a6e80d9..0b6fa245d54e 100644
> --- a/arch/powerpc/include/asm/vdso/gettimeofday.h
> +++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
> @@ -10,6 +10,7 @@
>     .cfi_startproc
>   	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
>   	mflr		r0
> +	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
>     .cfi_register lr, r0

The cfi_register should come directly after the mflr I think.

>   	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
>   	get_datapage	r5, r0
> @@ -19,7 +20,7 @@
>   	cmpwi		r3, 0
>   	mtlr		r0
>     .cfi_restore lr
> -	addi		r1, r1, STACK_FRAME_OVERHEAD
> +	addi		r1, r1, 2 * STACK_FRAME_OVERHEAD
>   	crclr		so
>   	beqlr+
>   	crset		so
> @@ -32,6 +33,7 @@
>     .cfi_startproc
>   	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
>   	mflr		r0
> +	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
>     .cfi_register lr, r0
>   	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
>   	get_datapage	r4, r0
> @@ -41,7 +43,7 @@
>   	crclr		so
>   	mtlr		r0
>     .cfi_restore lr
> -	addi		r1, r1, STACK_FRAME_OVERHEAD
> +	addi		r1, r1, 2 * STACK_FRAME_OVERHEAD
>   	blr
>     .cfi_endproc
>   .endm
>
>
>> There's also no code to load/restore the TOC pointer on BE, which I
>> think we'll need to handle.
>
> I see no code in the generated vdso64.so doing anything with r2, but if 
> you think that's needed, just let's do it:

Hmm, true.

The compiler will use the toc for globals (and possibly also for large
constants?)

AFAIK there's no way to disable use of the toc, or make it a build error
if it's needed.

But at least currently you can't add any global to the vdso code as it
won't link, because the .data and .bss are discarded.

At the same time it's much safer for us to just save/restore r2, and
probably in the noise performance wise.

So yeah we should probably do as below.

> commit 5a704d89bd5d7aac39194fb4c775f406905bf0a4
> Author: Christophe Leroy <christophe.leroy@csgroup.eu>
> Date:   Tue Aug 4 06:31:48 2020 +0000
>
>      Save and restore GOT
>
> diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h 
> b/arch/powerpc/include/asm/vdso/gettimeofday.h
> index 0b6fa245d54e..fa774086173b 100644
> --- a/arch/powerpc/include/asm/vdso/gettimeofday.h
> +++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
> @@ -13,10 +13,16 @@
>   	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
>     .cfi_register lr, r0
>   	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
> +#ifdef CONFIG_PPC64
> +	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
> +#endif
>   	get_datapage	r5, r0
>   	addi		r5, r5, VDSO_DATA_OFFSET
>   	bl		\funct
>   	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
> +#ifdef CONFIG_PPC64
> +	PPC_LL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
> +#endif
>   	cmpwi		r3, 0
>   	mtlr		r0
>     .cfi_restore lr
> @@ -36,10 +42,16 @@
>   	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
>     .cfi_register lr, r0
>   	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
> +#ifdef CONFIG_PPC64
> +	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
> +#endif
>   	get_datapage	r4, r0
>   	addi		r4, r4, VDSO_DATA_OFFSET
>   	bl		\funct
>   	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
> +#ifdef CONFIG_PPC64
> +	PPC_LL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
> +#endif
>   	crclr		so
>   	mtlr		r0
>     .cfi_restore lr


cheers

^ permalink raw reply

* Re: [PATCH v2 14/17] x86/setup: simplify reserve_crashkernel()
From: Baoquan He @ 2020-08-05  6:00 UTC (permalink / raw)
  To: Mike Rapoport
  Cc: Emil Renner Berthing, linux-sh, Peter Zijlstra, Dave Hansen,
	linux-mips, Max Filippov, Paul Mackerras, sparclinux, linux-riscv,
	Will Deacon, Stafford Horne, Marek Szyprowski, linux-arch,
	linux-s390, linux-c6x-dev, Yoshinori Sato, x86, Russell King,
	Mike Rapoport, clang-built-linux, Ingo Molnar, linux-arm-kernel,
	Catalin Marinas, uclinux-h8-devel, linux-xtensa, openrisc,
	Borislav Petkov, Andy Lutomirski, Paul Walmsley, Thomas Gleixner,
	Hari Bathini, Michal Simek, linux-mm, linuxppc-dev, linux-kernel,
	iommu, Palmer Dabbelt, Andrew Morton, Christoph Hellwig
In-Reply-To: <20200802163601.8189-15-rppt@kernel.org>

On 08/02/20 at 07:35pm, Mike Rapoport wrote:
> From: Mike Rapoport <rppt@linux.ibm.com>
> 
> * Replace magic numbers with defines
> * Replace memblock_find_in_range() + memblock_reserve() with
>   memblock_phys_alloc_range()
> * Stop checking for low memory size in reserve_crashkernel_low(). The
>   allocation from limited range will anyway fail if there is no enough
>   memory, so there is no need for extra traversal of memblock.memory
> 
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> ---
>  arch/x86/kernel/setup.c | 40 ++++++++++++++--------------------------
>  1 file changed, 14 insertions(+), 26 deletions(-)

Applied this patch on top of 5.8, crashkernel reservation works well.
And the code change looks good.

Reviewed-by: Baoquan He <bhe@redhat.com>

> 
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index d8de4053c5e8..d7ced6982524 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -419,13 +419,13 @@ static int __init reserve_crashkernel_low(void)
>  {
>  #ifdef CONFIG_X86_64
>  	unsigned long long base, low_base = 0, low_size = 0;
> -	unsigned long total_low_mem;
> +	unsigned long low_mem_limit;
>  	int ret;
>  
> -	total_low_mem = memblock_mem_size(1UL << (32 - PAGE_SHIFT));
> +	low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX);
>  
>  	/* crashkernel=Y,low */
> -	ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, &base);
> +	ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &low_size, &base);
>  	if (ret) {
>  		/*
>  		 * two parts from kernel/dma/swiotlb.c:
> @@ -443,23 +443,17 @@ static int __init reserve_crashkernel_low(void)
>  			return 0;
>  	}
>  
> -	low_base = memblock_find_in_range(0, 1ULL << 32, low_size, CRASH_ALIGN);
> +	low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
>  	if (!low_base) {
>  		pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
>  		       (unsigned long)(low_size >> 20));
>  		return -ENOMEM;
>  	}
>  
> -	ret = memblock_reserve(low_base, low_size);
> -	if (ret) {
> -		pr_err("%s: Error reserving crashkernel low memblock.\n", __func__);
> -		return ret;
> -	}
> -
> -	pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n",
> +	pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n",
>  		(unsigned long)(low_size >> 20),
>  		(unsigned long)(low_base >> 20),
> -		(unsigned long)(total_low_mem >> 20));
> +		(unsigned long)(low_mem_limit >> 20));
>  
>  	crashk_low_res.start = low_base;
>  	crashk_low_res.end   = low_base + low_size - 1;
> @@ -503,13 +497,13 @@ static void __init reserve_crashkernel(void)
>  		 * unless "crashkernel=size[KMG],high" is specified.
>  		 */
>  		if (!high)
> -			crash_base = memblock_find_in_range(CRASH_ALIGN,
> -						CRASH_ADDR_LOW_MAX,
> -						crash_size, CRASH_ALIGN);
> +			crash_base = memblock_phys_alloc_range(crash_size,
> +						CRASH_ALIGN, CRASH_ALIGN,
> +						CRASH_ADDR_LOW_MAX);
>  		if (!crash_base)
> -			crash_base = memblock_find_in_range(CRASH_ALIGN,
> -						CRASH_ADDR_HIGH_MAX,
> -						crash_size, CRASH_ALIGN);
> +			crash_base = memblock_phys_alloc_range(crash_size,
> +						CRASH_ALIGN, CRASH_ALIGN,
> +						CRASH_ADDR_HIGH_MAX);
>  		if (!crash_base) {
>  			pr_info("crashkernel reservation failed - No suitable area found.\n");
>  			return;
> @@ -517,19 +511,13 @@ static void __init reserve_crashkernel(void)
>  	} else {
>  		unsigned long long start;
>  
> -		start = memblock_find_in_range(crash_base,
> -					       crash_base + crash_size,
> -					       crash_size, 1 << 20);
> +		start = memblock_phys_alloc_range(crash_size, SZ_1M, crash_base,
> +						  crash_base + crash_size);
>  		if (start != crash_base) {
>  			pr_info("crashkernel reservation failed - memory is in use.\n");
>  			return;
>  		}
>  	}
> -	ret = memblock_reserve(crash_base, crash_size);
> -	if (ret) {
> -		pr_err("%s: Error reserving crashkernel memblock.\n", __func__);
> -		return;
> -	}
>  
>  	if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) {
>  		memblock_free(crash_base, crash_size);
> -- 
> 2.26.2
> 


^ permalink raw reply

* Re: [PATCH v2 13/17] x86/setup: simplify initrd relocation and reservation
From: Mike Rapoport @ 2020-08-05  5:59 UTC (permalink / raw)
  To: Baoquan He
  Cc: Emil Renner Berthing, linux-sh, Peter Zijlstra, Dave Hansen,
	linux-mips, Max Filippov, Paul Mackerras, sparclinux, linux-riscv,
	Will Deacon, Stafford Horne, Marek Szyprowski, linux-arch,
	linux-s390, linux-c6x-dev, Yoshinori Sato, x86, Russell King,
	Mike Rapoport, clang-built-linux, Ingo Molnar, linux-arm-kernel,
	Catalin Marinas, uclinux-h8-devel, linux-xtensa, openrisc,
	Borislav Petkov, Andy Lutomirski, Paul Walmsley, Thomas Gleixner,
	Hari Bathini, Michal Simek, linux-mm, linuxppc-dev, linux-kernel,
	iommu, Palmer Dabbelt, Andrew Morton, Christoph Hellwig
In-Reply-To: <20200805042024.GT10792@MiWiFi-R3L-srv>

On Wed, Aug 05, 2020 at 12:20:24PM +0800, Baoquan He wrote:
> On 08/02/20 at 07:35pm, Mike Rapoport wrote:
> > From: Mike Rapoport <rppt@linux.ibm.com>
> > 
> > Currently, initrd image is reserved very early during setup and then it
> > might be relocated and re-reserved after the initial physical memory
> > mapping is created. The "late" reservation of memblock verifies that mapped
> > memory size exceeds the size of initrd, the checks whether the relocation
>                                           ~ then?

Right, thanks!

> > required and, if yes, relocates inirtd to a new memory allocated from
> > memblock and frees the old location.

^ permalink raw reply

* Re: [PATCH v2 2/2] ASoC: fsl_sai: Refine enable and disable sequence for synchronous mode
From: Nicolin Chen @ 2020-08-05  5:15 UTC (permalink / raw)
  To: Shengjiu Wang
  Cc: Linux-ALSA, Timur Tabi, Xiubo Li, Fabio Estevam, Shengjiu Wang,
	Takashi Iwai, Liam Girdwood, Mark Brown, linuxppc-dev,
	linux-kernel
In-Reply-To: <CAA+D8ANv-qURC_wu3TzWiiiCAXC88Gc+WGssdjmuWoLPTRm3pA@mail.gmail.com>

On Wed, Aug 05, 2020 at 01:03:37PM +0800, Shengjiu Wang wrote:
> > Btw, the new fsl_sai_dir_is_synced() can be probably applied to
> > other places with a followup patch.

> Do you mean move it to the beginning of this file?

There are other existing places testing "sync[tx] && !sync[!tx]"
so you may submit another change to replace them. But, yea, will
be a good idea to move that helper function to the top.

^ permalink raw reply

* Re: [PATCH v2 2/2] ASoC: fsl_sai: Refine enable and disable sequence for synchronous mode
From: Shengjiu Wang @ 2020-08-05  5:03 UTC (permalink / raw)
  To: Nicolin Chen
  Cc: Linux-ALSA, Timur Tabi, Xiubo Li, Fabio Estevam, Shengjiu Wang,
	Takashi Iwai, Liam Girdwood, Mark Brown, linuxppc-dev,
	linux-kernel
In-Reply-To: <20200805041111.GB10174@Asurada-Nvidia>

On Wed, Aug 5, 2020 at 12:13 PM Nicolin Chen <nicoleotsuka@gmail.com> wrote:
>
> On Wed, Aug 05, 2020 at 10:23:53AM +0800, Shengjiu Wang wrote:
> > Tx synchronous with Rx:
> > The TCSR.TE is no need to enabled when only Rx is going to be enabled.
> > Check if need to disable RSCR.RE before disabling TCSR.TE.
> >
> > Rx synchronous with Tx:
> > The RCSR.RE is no need to enabled when only Tx is going to be enabled.
> > Check if need to disable TSCR.RE before disabling RCSR.TE.
>
> Please add to the commit log more context such as what we have
> discussed: what's the problem of the current driver, and why we
> _have_to_ apply this change though it's sightly against what RM
> recommends.
>
> (If thing is straightforward, it's okay to make the text short.
>  Yet I believe that this change deserves more than these lines.)
>
> One info that you should mention -- also the main reason why I'm
> convinced to add this change: trigger() is still in the shape of
> the early version where we only supported one operation mode --
> Tx synchronous with Rx. So we need an update for other modes.
>
> > Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
>
> The git-diff part looks good, please add this in next ver.:
>
> Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
>
> Btw, the new fsl_sai_dir_is_synced() can be probably applied to
> other places with a followup patch.
Do you mean move it to the beginning of this file?

best regards
wang shengjiu

^ permalink raw reply

* Re: [PATCH v4] selftests/powerpc: Fix pkey syscall redefinitions
From: Sachin Sant @ 2020-08-05  4:56 UTC (permalink / raw)
  To: Sandipan Das; +Cc: David Laight, linuxppc-dev, aneesh.kumar
In-Reply-To: <a4956d838bf59b0a71a2553c5ca81131ea8b49b9.1596561758.git.sandipan@linux.ibm.com>



> On 04-Aug-2020, at 11:01 PM, Sandipan Das <sandipan@linux.ibm.com> wrote:
> 
> On distros using older glibc versions, the pkey tests
> encounter build failures due to redefinition of the
> pkey syscall numbers.
> 
> For compatibility, commit 743f3544fffb added a wrapper
> for the gettid() syscall and included syscall.h if the
> version of glibc used is older than 2.30. This leads
> to different definitions of SYS_pkey_* as the ones in
> the pkey test header set numeric constants where as the
> ones from syscall.h reuse __NR_pkey_*. The compiler
> complains about redefinitions since they are different.
> 
> This replaces SYS_pkey_* definitions with __NR_pkey_*
> such that the definitions in both syscall.h and pkeys.h
> are alike. This way, if syscall.h has to be included
> for compatibility reasons, builds will still succeed.
> 
> Fixes: 743f3544fffb ("selftests/powerpc: Add wrapper for gettid")
> Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
> Suggested-by: David Laight <david.laight@aculab.com>
> Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
> Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>

Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>

Thanks
-Sachin

^ permalink raw reply

* [powerpc:next] BUILD SUCCESS 0c83b277ada72b585e6a3e52b067669df15bcedb
From: kernel test robot @ 2020-08-05  4:47 UTC (permalink / raw)
  To: Michael Ellerman; +Cc: linuxppc-dev

tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git  next
branch HEAD: 0c83b277ada72b585e6a3e52b067669df15bcedb  powerpc: Fix circular dependency between percpu.h and mmu.h

elapsed time: 925m

configs tested: 112
configs skipped: 7

The following configs have been built successfully.
More configs may be tested in the coming days.

arm                                 defconfig
arm64                            allyesconfig
arm64                               defconfig
arm                              allyesconfig
arm                              allmodconfig
sh                           se7750_defconfig
mips                            gpr_defconfig
arm                       spear13xx_defconfig
mips                      maltasmvp_defconfig
sh                           se7206_defconfig
arm                           spitz_defconfig
arm                        neponset_defconfig
arm                  colibri_pxa300_defconfig
arm                       netwinder_defconfig
arm                       versatile_defconfig
powerpc                mpc7448_hpc2_defconfig
mips                        bcm63xx_defconfig
sh                          r7785rp_defconfig
sh                            shmin_defconfig
arm                        multi_v7_defconfig
powerpc                      chrp32_defconfig
powerpc                     powernv_defconfig
sh                          sdk7786_defconfig
arm                     eseries_pxa_defconfig
m68k                          atari_defconfig
powerpc                       holly_defconfig
arm                        keystone_defconfig
powerpc                     mpc83xx_defconfig
sh                         ap325rxa_defconfig
arm                             mxs_defconfig
sh                            titan_defconfig
arc                              alldefconfig
m68k                        mvme147_defconfig
ia64                             allmodconfig
ia64                                defconfig
ia64                             allyesconfig
m68k                             allmodconfig
m68k                                defconfig
m68k                             allyesconfig
nios2                               defconfig
arc                              allyesconfig
nds32                             allnoconfig
c6x                              allyesconfig
nds32                               defconfig
nios2                            allyesconfig
csky                                defconfig
alpha                               defconfig
alpha                            allyesconfig
xtensa                           allyesconfig
h8300                            allyesconfig
arc                                 defconfig
sh                               allmodconfig
parisc                              defconfig
s390                             allyesconfig
parisc                           allyesconfig
s390                                defconfig
i386                             allyesconfig
sparc                            allyesconfig
sparc                               defconfig
i386                                defconfig
mips                             allyesconfig
mips                             allmodconfig
powerpc                             defconfig
powerpc                          allyesconfig
powerpc                          allmodconfig
powerpc                           allnoconfig
x86_64               randconfig-a006-20200804
x86_64               randconfig-a001-20200804
x86_64               randconfig-a004-20200804
x86_64               randconfig-a005-20200804
x86_64               randconfig-a002-20200804
x86_64               randconfig-a003-20200804
i386                 randconfig-a005-20200805
i386                 randconfig-a004-20200805
i386                 randconfig-a001-20200805
i386                 randconfig-a003-20200805
i386                 randconfig-a002-20200805
i386                 randconfig-a006-20200805
i386                 randconfig-a005-20200804
i386                 randconfig-a004-20200804
i386                 randconfig-a006-20200804
i386                 randconfig-a001-20200804
i386                 randconfig-a003-20200804
i386                 randconfig-a002-20200804
x86_64               randconfig-a013-20200805
x86_64               randconfig-a011-20200805
x86_64               randconfig-a012-20200805
x86_64               randconfig-a016-20200805
x86_64               randconfig-a015-20200805
x86_64               randconfig-a014-20200805
i386                 randconfig-a011-20200804
i386                 randconfig-a012-20200804
i386                 randconfig-a013-20200804
i386                 randconfig-a014-20200804
i386                 randconfig-a015-20200804
i386                 randconfig-a016-20200804
i386                 randconfig-a014-20200805
i386                 randconfig-a015-20200805
i386                 randconfig-a016-20200805
i386                 randconfig-a011-20200805
i386                 randconfig-a012-20200805
i386                 randconfig-a013-20200805
riscv                            allyesconfig
riscv                             allnoconfig
riscv                               defconfig
riscv                            allmodconfig
x86_64                                   rhel
x86_64                           allyesconfig
x86_64                    rhel-7.6-kselftests
x86_64                              defconfig
x86_64                               rhel-8.3
x86_64                                  kexec

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

^ permalink raw reply

* [powerpc:merge] BUILD SUCCESS 14fd53d1e5ee7350564cac75e336f8c0dea13bc9
From: kernel test robot @ 2020-08-05  4:47 UTC (permalink / raw)
  To: Michael Ellerman; +Cc: linuxppc-dev

tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git  merge
branch HEAD: 14fd53d1e5ee7350564cac75e336f8c0dea13bc9  Automatic merge of 'master', 'next' and 'fixes' (2020-08-04 23:16)

elapsed time: 927m

configs tested: 108
configs skipped: 7

The following configs have been built successfully.
More configs may be tested in the coming days.

arm                                 defconfig
arm64                            allyesconfig
arm64                               defconfig
arm                              allyesconfig
arm                              allmodconfig
sh                           se7750_defconfig
mips                            gpr_defconfig
arm                       spear13xx_defconfig
mips                      maltasmvp_defconfig
sh                           se7206_defconfig
arm                           spitz_defconfig
arm                        neponset_defconfig
arm                        shmobile_defconfig
powerpc                      pmac32_defconfig
sh                        sh7785lcr_defconfig
mips                         cobalt_defconfig
mips                         rt305x_defconfig
mips                 pnx8335_stb225_defconfig
ia64                          tiger_defconfig
arm                          ep93xx_defconfig
arm                  colibri_pxa300_defconfig
arm                       netwinder_defconfig
arm                       versatile_defconfig
powerpc                mpc7448_hpc2_defconfig
mips                        bcm63xx_defconfig
sh                          r7785rp_defconfig
sh                            shmin_defconfig
arm                        multi_v7_defconfig
mips                         tb0287_defconfig
sh                          rsk7269_defconfig
mips                        jmr3927_defconfig
xtensa                          iss_defconfig
powerpc                      chrp32_defconfig
powerpc                     powernv_defconfig
sh                          sdk7786_defconfig
ia64                             allmodconfig
ia64                                defconfig
ia64                             allyesconfig
m68k                             allmodconfig
m68k                                defconfig
m68k                             allyesconfig
nios2                               defconfig
arc                              allyesconfig
nds32                             allnoconfig
c6x                              allyesconfig
nds32                               defconfig
nios2                            allyesconfig
csky                                defconfig
alpha                               defconfig
alpha                            allyesconfig
xtensa                           allyesconfig
h8300                            allyesconfig
arc                                 defconfig
sh                               allmodconfig
parisc                              defconfig
s390                             allyesconfig
parisc                           allyesconfig
s390                                defconfig
i386                             allyesconfig
sparc                            allyesconfig
sparc                               defconfig
i386                                defconfig
mips                             allyesconfig
mips                             allmodconfig
powerpc                             defconfig
powerpc                          allyesconfig
powerpc                          allmodconfig
powerpc                           allnoconfig
i386                 randconfig-a005-20200804
i386                 randconfig-a004-20200804
i386                 randconfig-a001-20200804
i386                 randconfig-a003-20200804
i386                 randconfig-a002-20200804
i386                 randconfig-a006-20200804
i386                 randconfig-a005-20200805
i386                 randconfig-a004-20200805
i386                 randconfig-a001-20200805
i386                 randconfig-a003-20200805
i386                 randconfig-a002-20200805
i386                 randconfig-a006-20200805
x86_64               randconfig-a013-20200805
x86_64               randconfig-a011-20200805
x86_64               randconfig-a012-20200805
x86_64               randconfig-a016-20200805
x86_64               randconfig-a015-20200805
x86_64               randconfig-a014-20200805
i386                 randconfig-a011-20200805
i386                 randconfig-a012-20200805
i386                 randconfig-a013-20200805
i386                 randconfig-a014-20200805
i386                 randconfig-a015-20200805
i386                 randconfig-a016-20200805
x86_64               randconfig-a006-20200804
x86_64               randconfig-a001-20200804
x86_64               randconfig-a004-20200804
x86_64               randconfig-a005-20200804
x86_64               randconfig-a002-20200804
x86_64               randconfig-a003-20200804
riscv                            allyesconfig
riscv                             allnoconfig
riscv                               defconfig
riscv                            allmodconfig
x86_64                                   rhel
x86_64                           allyesconfig
x86_64                    rhel-7.6-kselftests
x86_64                              defconfig
x86_64                               rhel-8.3
x86_64                                  kexec

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

^ permalink raw reply

* Re: [PATCH] powerpc/pseries/hotplug-cpu: increase wait time for vCPU death
From: Michael Roth @ 2020-08-05  4:37 UTC (permalink / raw)
  To: Greg Kurz, Michael Ellerman
  Cc: Nathan Lynch, linuxppc-dev, Cedric Le Goater,
	Thiago Jung Bauermann
In-Reply-To: <87zh79yen7.fsf@mpe.ellerman.id.au>

Quoting Michael Ellerman (2020-08-04 22:07:08)
> Greg Kurz <groug@kaod.org> writes:
> > On Tue, 04 Aug 2020 23:35:10 +1000
> > Michael Ellerman <mpe@ellerman.id.au> wrote:
> >> There is a bit of history to this code, but not in a good way :)
> >> 
> >> Michael Roth <mdroth@linux.vnet.ibm.com> writes:
> >> > For a power9 KVM guest with XIVE enabled, running a test loop
> >> > where we hotplug 384 vcpus and then unplug them, the following traces
> >> > can be seen (generally within a few loops) either from the unplugged
> >> > vcpu:
> >> >
> >> >   [ 1767.353447] cpu 65 (hwid 65) Ready to die...
> >> >   [ 1767.952096] Querying DEAD? cpu 66 (66) shows 2
> >> >   [ 1767.952311] list_del corruption. next->prev should be c00a000002470208, but was c00a000002470048
> >> ...
> >> >
> >> > At that point the worker thread assumes the unplugged CPU is in some
> >> > unknown/dead state and procedes with the cleanup, causing the race with
> >> > the XIVE cleanup code executed by the unplugged CPU.
> >> >
> >> > Fix this by inserting an msleep() after each RTAS call to avoid
> >> 
> >> We previously had an msleep(), but it was removed:
> >> 
> >>   b906cfa397fd ("powerpc/pseries: Fix cpu hotplug")
> >
> > Ah, I hadn't seen that one...
> >
> >> > pseries_cpu_die() returning prematurely, and double the number of
> >> > attempts so we wait at least a total of 5 seconds. While this isn't an
> >> > ideal solution, it is similar to how we dealt with a similar issue for
> >> > cede_offline mode in the past (940ce422a3).
> >> 
> >> Thiago tried to fix this previously but there was a bit of discussion
> >> that didn't quite resolve:
> >> 
> >>   https://lore.kernel.org/linuxppc-dev/20190423223914.3882-1-bauerman@linux.ibm.com/
> >
> > Yeah it appears that the motivation at the time was to make the "Querying DEAD?"
> > messages to disappear and to avoid potentially concurrent calls to rtas-stop-self
> > which is prohibited by PAPR... not fixing actual crashes.
> 
> I'm pretty sure at one point we were triggering crashes *in* RTAS via
> this path, I think that got resolved.
> 
> >> Spinning forever seems like a bad idea, but as has been demonstrated at
> >> least twice now, continuing when we don't know the state of the other
> >> CPU can lead to straight up crashes.
> >> 
> >> So I think I'm persuaded that it's preferable to have the kernel stuck
> >> spinning rather than oopsing.
> >> 
> >
> > +1
> >
> >> I'm 50/50 on whether we should have a cond_resched() in the loop. My
> >> first instinct is no, if we're stuck here for 20s a stack trace would be
> >> good. But then we will probably hit that on some big and/or heavily
> >> loaded machine.
> >> 
> >> So possibly we should call cond_resched() but have some custom logic in
> >> the loop to print a warning if we are stuck for more than some
> >> sufficiently long amount of time.
> >
> > How long should that be ?
> 
> Yeah good question.
> 
> I guess step one would be seeing how long it can take on the 384 vcpu
> machine. And we can probably test on some other big machines.
> 
> Hopefully Nathan can give us some idea of how long he's seen it take on
> large systems? I know he was concerned about the 20s timeout of the
> softlockup detector.
> 
> Maybe a minute or two?

Hmm, so I took a stab at this where I called cond_resched() after
every 5 seconds of polling and printed a warning at the same time (FWIW
that doesn't seem to trigger any warnings on a loaded 96-core mihawk
system using KVM running the 384vcpu unplug loop)

But it sounds like that's not quite what you had in mind. How frequently
do you think we should call cond_resched()? Maybe after 25 iterations
of polling smp_query_cpu_stopped() to keep original behavior somewhat
similar?

I'll let the current patch run on the mihawk system overnight in the
meantime so we at least have that data point, but would be good to
know what things look like a large pHyp machine.

Thanks!

> 
> >> > Fixes: eac1e731b59ee ("powerpc/xive: guest exploitation of the XIVE interrupt controller")
> >> > Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1856588
> >> 
> >> This is not public.
> >
> > I'll have a look at changing that.
> 
> Thanks.
> 
> cheers

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