[kvm-unit-tests PATCH v8 16/35] powerpc: Support powernv machine with QEMU TCG

Nicholas Piggin
2024-04-05T08:36:52Z

Add support for QEMU's powernv machine. This uses standard firmware
(skiboot) rather than a minimal firmware shim.

Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
lib/powerpc/asm/processor.h | 23 +++++++++++
lib/powerpc/asm/reg.h | 4 ++
lib/powerpc/hcall.c | 4 +-
lib/powerpc/io.c | 27 ++++++++++++-
lib/powerpc/io.h | 6 +++
lib/powerpc/processor.c | 37 ++++++++++++++++++
lib/powerpc/setup.c | 14 +++++--
lib/ppc64/asm/opal.h | 15 ++++++++
lib/ppc64/opal-calls.S | 50 ++++++++++++++++++++++++
lib/ppc64/opal.c | 76 +++++++++++++++++++++++++++++++++++++
powerpc/Makefile.ppc64 | 2 +
powerpc/cstart64.S | 7 ++++
powerpc/run | 42 ++++++++++++++++----
powerpc/unittests.cfg | 10 ++++-
14 files changed, 301 insertions(+), 16 deletions(-)
create mode 100644 lib/ppc64/asm/opal.h
create mode 100644 lib/ppc64/opal-calls.S
create mode 100644 lib/ppc64/opal.c

diff --git a/lib/powerpc/asm/processor.h b/lib/powerpc/asm/processor.h
index e415f9235..9d8061962 100644
--- a/lib/powerpc/asm/processor.h
+++ b/lib/powerpc/asm/processor.h
@@ -10,6 +10,8 @@ void handle_exception(int trap, void (*func)(struct pt_regs *, void *), void *);
void do_handle_exception(struct pt_regs *regs);
#endif /* __ASSEMBLY__ */

+extern bool cpu_has_hv;
+
static inline uint64_t mfspr(int nr)
{
uint64_t ret;
@@ -38,4 +40,25 @@ static inline void mtmsr(uint64_t msr)
asm volatile ("mtmsrd %[msr]" :: [msr] "r" (msr) : "memory");
}

+/*
+ * This returns true on PowerNV / OPAL machines which run in hypervisor
+ * mode. False on pseries / PAPR machines that run in guest mode.
+ */
+static inline bool machine_is_powernv(void)
+{
+ return cpu_has_hv;
+}
+
+/*
+ * This returns true on pseries / PAPR / KVM machines which run under a
+ * hypervisor or QEMU pseries machine. False for PowerNV / OPAL.
+ */
+static inline bool machine_is_pseries(void)
+{
+ return !machine_is_powernv();
+}
+
+void enable_mcheck(void);
+void disable_mcheck(void);
+
#endif /* _ASMPOWERPC_PROCESSOR_H_ */
diff --git a/lib/powerpc/asm/reg.h b/lib/powerpc/asm/reg.h
index c80b32059..782e75527 100644
--- a/lib/powerpc/asm/reg.h
+++ b/lib/powerpc/asm/reg.h
@@ -30,7 +30,11 @@
#define MMCR0_PMAO UL(0x00000080)

/* Machine State Register definitions: */
+#define MSR_LE_BIT 0
#define MSR_EE_BIT 15 /* External Interrupts Enable */
+#define MSR_HV_BIT 60 /* Hypervisor mode */
#define MSR_SF_BIT 63 /* 64-bit mode */

+#define MSR_ME UL(0x1000)
+
#endif
diff --git a/lib/powerpc/hcall.c b/lib/powerpc/hcall.c
index b4d39ac65..45f201315 100644
--- a/lib/powerpc/hcall.c
+++ b/lib/powerpc/hcall.c
@@ -25,7 +25,7 @@ int hcall_have_broken_sc1(void)
return r3 == (unsigned long)H_PRIVILEGE;
}

-void putchar(int c)
+void papr_putchar(int c)
{
unsigned long vty = 0; /* 0 == default */
unsigned long nr_chars = 1;
@@ -34,7 +34,7 @@ void putchar(int c)
hcall(H_PUT_TERM_CHAR, vty, nr_chars, chars);
}

-int __getchar(void)
+int __papr_getchar(void)
{
register unsigned long r3 asm("r3") = H_GET_TERM_CHAR;
register unsigned long r4 asm("r4") = 0; /* 0 == default vty */
diff --git a/lib/powerpc/io.c b/lib/powerpc/io.c
index a381688bc..ab7bb843c 100644
--- a/lib/powerpc/io.c
+++ b/lib/powerpc/io.c
@@ -9,13 +9,33 @@
#include <asm/spinlock.h>
#include <asm/rtas.h>
#include <asm/setup.h>
+#include <asm/processor.h>
#include "io.h"

static struct spinlock print_lock;

+void putchar(int c)
+{
+ if (machine_is_powernv())
+ opal_putchar(c);
+ else
+ papr_putchar(c);
+}
+
+int __getchar(void)
+{
+ if (machine_is_powernv())
+ return __opal_getchar();
+ else
+ return __papr_getchar();
+}
+
void io_init(void)
{
- rtas_init();
+ if (machine_is_powernv())
+ assert(!opal_init());
+ else
+ rtas_init();
}

void puts(const char *s)
@@ -38,7 +58,10 @@ void exit(int code)
// FIXME: change this print-exit/rtas-poweroff to chr_testdev_exit(),
// maybe by plugging chr-testdev into a spapr-vty.
printf("\nEXIT: STATUS=%d\n", ((code) << 1) | 1);
- rtas_power_off();
+ if (machine_is_powernv())
+ opal_power_off();
+ else
+ rtas_power_off();
halt(code);
__builtin_unreachable();
}
diff --git a/lib/powerpc/io.h b/lib/powerpc/io.h
index d4f21ba15..943bf142b 100644
--- a/lib/powerpc/io.h
+++ b/lib/powerpc/io.h
@@ -8,6 +8,12 @@
#define _POWERPC_IO_H_

extern void io_init(void);
+extern int opal_init(void);
+extern void opal_power_off(void);
extern void putchar(int c);
+extern void opal_putchar(int c);
+extern void papr_putchar(int c);
+extern int __opal_getchar(void);
+extern int __papr_getchar(void);

#endif
diff --git a/lib/powerpc/processor.c b/lib/powerpc/processor.c
index 114584024..1b4bb0d61 100644
--- a/lib/powerpc/processor.c
+++ b/lib/powerpc/processor.c
@@ -84,6 +84,16 @@ void sleep_tb(uint64_t cycles)
{
uint64_t start, end, now;

+ if (!machine_is_pseries()) {
+ /*
+ * P9/10 Could use 'stop' to sleep here which would be
+ * interesting. stop with ESL=0 should be simple enough, ESL=1
+ * would require SRESET based wakeup which is more involved.
+ */
+ delay(cycles);
+ return;
+ }
+
start = now = get_tb();
end = start + cycles;

@@ -120,3 +130,30 @@ void usleep(uint64_t us)
{
sleep_tb((us * tb_hz) / 1000000);
}
+
+static void rfid_msr(uint64_t msr)
+{
+ uint64_t tmp;
+
+ asm volatile(
+ "mtsrr1 %1 \n\
+ bl 0f \n\
+ 0: \n\
+ mflr %0 \n\
+ addi %0,%0,1f-0b \n\
+ mtsrr0 %0 \n\
+ rfid \n\
+ 1: \n"
+ : "=r"(tmp) : "r"(msr) : "lr");
+}
+
+void enable_mcheck(void)
+{
+ /* This is a no-op on pseries */
+ rfid_msr(mfmsr() | MSR_ME);
+}
+
+void disable_mcheck(void)
+{
+ rfid_msr(mfmsr() & ~MSR_ME);
+}
diff --git a/lib/powerpc/setup.c b/lib/powerpc/setup.c
index d98f66fae..89e5157f2 100644
--- a/lib/powerpc/setup.c
+++ b/lib/powerpc/setup.c
@@ -19,6 +19,7 @@
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/ptrace.h>
+#include <asm/processor.h>
#include <asm/hcall.h>
#include "io.h"

@@ -85,6 +86,8 @@ static void cpu_set(int fdtnode, u64 regval, void *info)
}
}

+bool cpu_has_hv;
+
static void cpu_init(void)
{
struct cpu_set_params params;
@@ -98,12 +101,13 @@ static void cpu_init(void)
tb_hz = params.tb_hz;

/* Interrupt Endianness */
-
+ if (machine_is_pseries()) {
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
- hcall(H_SET_MODE, 1, 4, 0, 0);
+ hcall(H_SET_MODE, 1, 4, 0, 0);
#else
- hcall(H_SET_MODE, 0, 4, 0, 0);
+ hcall(H_SET_MODE, 0, 4, 0, 0);
#endif
+ }
}

static void mem_init(phys_addr_t freemem_start)
@@ -159,6 +163,10 @@ void setup(const void *fdt)
u32 fdt_size;
int ret;

+ cpu_has_hv = !!(mfmsr() & (1ULL << MSR_HV_BIT));
+
+ enable_mcheck();
+
/*
* Before calling mem_init we need to move the fdt and initrd
* to safe locations. We move them to construct the memory
diff --git a/lib/ppc64/asm/opal.h b/lib/ppc64/asm/opal.h
new file mode 100644
index 000000000..de64e2c8d
--- /dev/null
+++ b/lib/ppc64/asm/opal.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _ASMPPC64_OPAL_H_
+#define _ASMPPC64_OPAL_H_
+
+#define OPAL_SUCCESS 0
+
+#define OPAL_CONSOLE_WRITE 1
+#define OPAL_CONSOLE_READ 2
+#define OPAL_CEC_POWER_DOWN 5
+#define OPAL_POLL_EVENTS 10
+#define OPAL_REINIT_CPUS 70
+# define OPAL_REINIT_CPUS_HILE_BE (1 << 0)
+# define OPAL_REINIT_CPUS_HILE_LE (1 << 1)
+
+#endif
diff --git a/lib/ppc64/opal-calls.S b/lib/ppc64/opal-calls.S
new file mode 100644
index 000000000..8cb4c3e91
--- /dev/null
+++ b/lib/ppc64/opal-calls.S
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2016 IBM Corporation.
+ */
+
+#include <asm/ppc_asm.h>
+
+ .text
+ .globl opal_call
+opal_call:
+ mr r0,r3
+ mr r3,r4
+ mr r4,r5
+ mr r5,r6
+ mr r6,r7
+ mflr r11
+ std r11,16(r1)
+ mfcr r12
+ stw r12,8(r1)
+ std r2,-8(r1) /* use redzone */
+
+ /* Set opal return address */
+ LOAD_REG_ADDR(r11, opal_return)
+ mtlr r11
+ mfmsr r12
+ std r12,-16(r1) /* use redzone */
+
+ /* switch to BE when we enter OPAL */
+ li r11,(1 << MSR_LE_BIT)
+ ori r11,r11,(1 << MSR_EE_BIT)
+ andc r12,r12,r11
+ mtspr SPR_HSRR1,r12
+
+ /* load the opal call entry point and base */
+ LOAD_REG_ADDR(r11, opal)
+ ld r12,8(r11)
+ ld r2,0(r11)
+ mtspr SPR_HSRR0,r12
+ hrfid
+
+opal_return:
+ FIXUP_ENDIAN
+ ld r12,-16(r1) /* use redzone */
+ mtmsrd r12
+ ld r2,-8(r1) /* use redzone */
+ lwz r11,8(r1);
+ ld r12,16(r1)
+ mtcr r11;
+ mtlr r12
+ blr
diff --git a/lib/ppc64/opal.c b/lib/ppc64/opal.c
new file mode 100644
index 000000000..63fe42ae6
--- /dev/null
+++ b/lib/ppc64/opal.c
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * OPAL call helpers
+ */
+#include <asm/opal.h>
+#include <libcflat.h>
+#include <libfdt/libfdt.h>
+#include <devicetree.h>
+#include <asm/io.h>
+#include "../powerpc/io.h"
+
+struct opal {
+ uint64_t base;
+ uint64_t entry;
+} opal;
+
+extern int64_t opal_call(int64_t token, int64_t arg1, int64_t arg2, int64_t arg3);
+
+int opal_init(void)
+{
+ const struct fdt_property *prop;
+ int node, len;
+
+ node = fdt_path_offset(dt_fdt(), "/ibm,opal");
+ if (node < 0)
+ return -1;
+
+ prop = fdt_get_property(dt_fdt(), node, "opal-base-address", &len);
+ if (!prop)
+ return -1;
+ opal.base = fdt64_to_cpu(*(uint64_t *)prop->data);
+
+ prop = fdt_get_property(dt_fdt(), node, "opal-entry-address", &len);
+ if (!prop)
+ return -1;
+ opal.entry = fdt64_to_cpu(*(uint64_t *)prop->data);
+
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+ if (opal_call(OPAL_REINIT_CPUS, OPAL_REINIT_CPUS_HILE_LE, 0, 0) != OPAL_SUCCESS)
+ return -1;
+#endif
+
+ return 0;
+}
+
+extern void opal_power_off(void)
+{
+ opal_call(OPAL_CEC_POWER_DOWN, 0, 0, 0);
+ while (true)
+ opal_call(OPAL_POLL_EVENTS, 0, 0, 0);
+}
+
+void opal_putchar(int c)
+{
+ unsigned long vty = 0; /* 0 == default */
+ unsigned long nr_chars = cpu_to_be64(1);
+ char ch = c;
+
+ opal_call(OPAL_CONSOLE_WRITE, (int64_t)vty, (int64_t)&nr_chars, (int64_t)&ch);
+}
+
+int __opal_getchar(void)
+{
+ unsigned long vty = 0; /* 0 == default */
+ unsigned long nr_chars = cpu_to_be64(1);
+ char ch;
+ int rc;
+
+ rc = opal_call(OPAL_CONSOLE_READ, (int64_t)vty, (int64_t)&nr_chars, (int64_t)&ch);
+ if (rc != OPAL_SUCCESS)
+ return -1;
+ if (nr_chars == 0)
+ return -1;
+
+ return ch;
+}
diff --git a/powerpc/Makefile.ppc64 b/powerpc/Makefile.ppc64
index eb682c226..a18a9628f 100644
--- a/powerpc/Makefile.ppc64
+++ b/powerpc/Makefile.ppc64
@@ -18,6 +18,8 @@ reloc.o = $(TEST_DIR)/reloc64.o

OBJDIRS += lib/ppc64
cflatobjs += lib/ppc64/stack.o
+cflatobjs += lib/ppc64/opal.o
+cflatobjs += lib/ppc64/opal-calls.o

# ppc64 specific tests
tests = $(TEST_DIR)/spapr_vpa.elf
diff --git a/powerpc/cstart64.S b/powerpc/cstart64.S
index 07d297f61..405cb0561 100644
--- a/powerpc/cstart64.S
+++ b/powerpc/cstart64.S
@@ -97,6 +97,13 @@ start:
sync
isync

+ /* powernv machine does not check broken_sc1 */
+ mfmsr r3
+ li r4,1
+ sldi r4,r4,MSR_HV_BIT
+ and. r3,r3,r4
+ bne 1f
+
/* patch sc1 if needed */
bl hcall_have_broken_sc1
cmpwi r3, 0
diff --git a/powerpc/run b/powerpc/run
index 5cdb94194..172f32a46 100755
--- a/powerpc/run
+++ b/powerpc/run
@@ -1,5 +1,14 @@
#!/usr/bin/env bash

+get_qemu_machine ()
+{
+ if [ "$MACHINE" ]; then
+ echo $MACHINE
+ else
+ echo pseries
+ fi
+}
+
if [ -z "$KUT_STANDALONE" ]; then
if [ ! -f config.mak ]; then
echo "run ./configure && make first. See ./configure -h"
@@ -11,24 +20,41 @@ fi

set_qemu_accelerator || exit $?

+MACHINE=$(get_qemu_machine) ||
+ exit $?
+
+if [[ "$MACHINE" == "powernv"* ]] && [ "$ACCEL" = "kvm" ]; then
+ echo "PowerNV machine does not support KVM. ACCEL=tcg must be specified."
+ exit 2
+fi
+
qemu=$(search_qemu_binary) ||
exit $?

-if ! $qemu -machine '?' 2>&1 | grep 'pseries' > /dev/null; then
- echo "$qemu doesn't support pSeries ('-machine pseries'). Exiting."
+if ! $qemu -machine '?' 2>&1 | grep $MACHINE > /dev/null; then
+ echo "$qemu doesn't support '-machine $MACHINE'. Exiting."
exit 2
fi

-M='-machine pseries'
+M="-machine $MACHINE"
M+=",accel=$ACCEL$ACCEL_PROPS"
+B=""
+D=""
+
+if [[ "$MACHINE" == "pseries"* ]] ; then
+ if [[ "$ACCEL" == "tcg" ]] ; then
+ M+=",cap-cfpc=broken,cap-sbbc=broken,cap-ibs=broken,cap-ccf-assist=off"
+ elif [[ "$ACCEL" == "kvm" ]] ; then
+ M+=",cap-ccf-assist=off"
+ fi
+ B+="-bios $FIRMWARE"
+fi

-if [[ "$ACCEL" == "tcg" ]] ; then
- M+=",cap-cfpc=broken,cap-sbbc=broken,cap-ibs=broken,cap-ccf-assist=off"
-elif [[ "$ACCEL" == "kvm" ]] ; then
- M+=",cap-ccf-assist=off"
+if [[ "$MACHINE" == "powernv"* ]] ; then
+ D+="-device ipmi-bmc-sim,id=bmc0 -device isa-ipmi-bt,bmc=bmc0,irq=10"
fi

-command="$qemu -nodefaults $M -bios $FIRMWARE"
+command="$qemu -nodefaults $M $B $D"
command+=" -display none -serial stdio -kernel"
command="$(migration_cmd) $(timeout_cmd) $command"

diff --git a/powerpc/unittests.cfg b/powerpc/unittests.cfg
index 4929e71a1..3c3783ba6 100644
--- a/powerpc/unittests.cfg
+++ b/powerpc/unittests.cfg
@@ -15,11 +15,12 @@
[selftest-setup]
file = selftest.elf
smp = 2
-extra_params = -m 256 -append 'setup smp=2 mem=256'
+extra_params = -m 1g -append 'setup smp=2 mem=1024'
groups = selftest

[selftest-migration]
file = selftest-migration.elf
+machine = pseries
groups = selftest migration
# TODO: Remove accel=kvm once the following TCG migration fix has been merged:
# https://lore.kernel.org/qemu-devel/20240219061731.232570-1-npiggin@gmail.com/
@@ -40,24 +41,29 @@ groups = migration

[spapr_hcall]
file = spapr_hcall.elf
+machine = pseries

[spapr_vpa]
file = spapr_vpa.elf
+machine = pseries

[rtas-get-time-of-day]
file = rtas.elf
+machine = pseries
timeout = 5
extra_params = -append "get-time-of-day date=$(date +%s)"
groups = rtas

[rtas-get-time-of-day-base]
file = rtas.elf
+machine = pseries
timeout = 5
extra_params = -rtc base="2006-06-17" -append "get-time-of-day date=$(date --date="2006-06-17 UTC" +%s)"
groups = rtas

[rtas-set-time-of-day]
file = rtas.elf
+machine = pseries
extra_params = -append "set-time-of-day"
timeout = 5
groups = rtas
@@ -67,6 +73,7 @@ file = emulator.elf

[h_cede_tm]
file = tm.elf
+machine = pseries
accel = kvm
smp = 2,threads=2
extra_params = -machine cap-htm=on -append "h_cede_tm"
@@ -77,5 +84,6 @@ file = sprs.elf

[sprs-migration]
file = sprs.elf
+machine = pseries
extra_params = -append '-w'
groups = migration
--
2.43.0