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* [PATCH v2 08/10] ARM: KVM: introduce per-vcpu HYP Configuration Register
From: Marc Zyngier @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390402602-22777-1-git-send-email-marc.zyngier@arm.com>

So far, KVM/ARM used a fixed HCR configuration per guest, except for
the VI/VF/VA bits to control the interrupt in absence of VGIC.

With the upcoming need to dynamically reconfigure trapping, it becomes
necessary to allow the HCR to be changed on a per-vcpu basis.

The fix here is to mimic what KVM/arm64 already does: a per vcpu HCR
field, initialized at setup time.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 arch/arm/include/asm/kvm_arm.h  | 1 -
 arch/arm/include/asm/kvm_host.h | 9 ++++++---
 arch/arm/kernel/asm-offsets.c   | 1 +
 arch/arm/kvm/guest.c            | 1 +
 arch/arm/kvm/interrupts_head.S  | 9 +++------
 5 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index 1d3153c..a843e74 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -69,7 +69,6 @@
 #define HCR_GUEST_MASK (HCR_TSC | HCR_TSW | HCR_TWI | HCR_VM | HCR_BSU_IS | \
 			HCR_FB | HCR_TAC | HCR_AMO | HCR_IMO | HCR_FMO | \
 			HCR_TWE | HCR_SWIO | HCR_TIDCP)
-#define HCR_VIRT_EXCP_MASK (HCR_VA | HCR_VI | HCR_VF)
 
 /* System Control Register (SCTLR) bits */
 #define SCTLR_TE	(1 << 30)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index ba6d33a..918fdc1 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -101,6 +101,12 @@ struct kvm_vcpu_arch {
 	/* The CPU type we expose to the VM */
 	u32 midr;
 
+	/* HYP trapping configuration */
+	u32 hcr;
+
+	/* Interrupt related fields */
+	u32 irq_lines;		/* IRQ and FIQ levels */
+
 	/* Exception Information */
 	struct kvm_vcpu_fault_info fault;
 
@@ -128,9 +134,6 @@ struct kvm_vcpu_arch {
 	/* IO related fields */
 	struct kvm_decode mmio_decode;
 
-	/* Interrupt related fields */
-	u32 irq_lines;		/* IRQ and FIQ levels */
-
 	/* Cache some mmu pages needed inside spinlock regions */
 	struct kvm_mmu_memory_cache mmu_page_cache;
 
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index dbe0476..713e807 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -174,6 +174,7 @@ int main(void)
   DEFINE(VCPU_FIQ_REGS,		offsetof(struct kvm_vcpu, arch.regs.fiq_regs));
   DEFINE(VCPU_PC,		offsetof(struct kvm_vcpu, arch.regs.usr_regs.ARM_pc));
   DEFINE(VCPU_CPSR,		offsetof(struct kvm_vcpu, arch.regs.usr_regs.ARM_cpsr));
+  DEFINE(VCPU_HCR,		offsetof(struct kvm_vcpu, arch.hcr));
   DEFINE(VCPU_IRQ_LINES,	offsetof(struct kvm_vcpu, arch.irq_lines));
   DEFINE(VCPU_HSR,		offsetof(struct kvm_vcpu, arch.fault.hsr));
   DEFINE(VCPU_HxFAR,		offsetof(struct kvm_vcpu, arch.fault.hxfar));
diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c
index 20f8d97..0c8c044 100644
--- a/arch/arm/kvm/guest.c
+++ b/arch/arm/kvm/guest.c
@@ -38,6 +38,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
 
 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 {
+	vcpu->arch.hcr = HCR_GUEST_MASK;
 	return 0;
 }
 
diff --git a/arch/arm/kvm/interrupts_head.S b/arch/arm/kvm/interrupts_head.S
index 4a2a97a..7cb41e1 100644
--- a/arch/arm/kvm/interrupts_head.S
+++ b/arch/arm/kvm/interrupts_head.S
@@ -597,17 +597,14 @@ vcpu	.req	r0		@ vcpu pointer always in r0
 
 /* Enable/Disable: stage-2 trans., trap interrupts, trap wfi, trap smc */
 .macro configure_hyp_role operation
-	mrc	p15, 4, r2, c1, c1, 0	@ HCR
-	bic	r2, r2, #HCR_VIRT_EXCP_MASK
-	ldr	r3, =HCR_GUEST_MASK
 	.if \operation == vmentry
-	orr	r2, r2, r3
+	ldr	r2, [vcpu, #VCPU_HCR]
 	ldr	r3, [vcpu, #VCPU_IRQ_LINES]
 	orr	r2, r2, r3
 	.else
-	bic	r2, r2, r3
+	mov	r2, #0
 	.endif
-	mcr	p15, 4, r2, c1, c1, 0
+	mcr	p15, 4, r2, c1, c1, 0	@ HCR
 .endm
 
 .macro load_vcpu
-- 
1.8.3.4

^ permalink raw reply related

* [PATCH v2 07/10] ARM: KVM: fix ordering of 64bit coprocessor accesses
From: Marc Zyngier @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390402602-22777-1-git-send-email-marc.zyngier@arm.com>

Commit 240e99cbd00a (ARM: KVM: Fix 64-bit coprocessor handling)
added an ordering dependency for the 64bit registers.

The order described is: CRn, CRm, Op1, Op2, 64bit-first.

Unfortunately, the implementation is: CRn, 64bit-first, CRm...

Move the 64bit test to be last in order to match the documentation.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 arch/arm/kvm/coproc.h | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h
index c5ad7ff..1a44bbe 100644
--- a/arch/arm/kvm/coproc.h
+++ b/arch/arm/kvm/coproc.h
@@ -135,13 +135,13 @@ static inline int cmp_reg(const struct coproc_reg *i1,
 		return -1;
 	if (i1->CRn != i2->CRn)
 		return i1->CRn - i2->CRn;
-	if (i1->is_64 != i2->is_64)
-		return i2->is_64 - i1->is_64;
 	if (i1->CRm != i2->CRm)
 		return i1->CRm - i2->CRm;
 	if (i1->Op1 != i2->Op1)
 		return i1->Op1 - i2->Op1;
-	return i1->Op2 - i2->Op2;
+	if (i1->Op2 != i2->Op2)
+		return i1->Op2 - i2->Op2;
+	return i2->is_64 - i1->is_64;
 }
 
 
@@ -153,4 +153,8 @@ static inline int cmp_reg(const struct coproc_reg *i1,
 #define is64		.is_64 = true
 #define is32		.is_64 = false
 
+bool access_sctlr(struct kvm_vcpu *vcpu,
+		  const struct coproc_params *p,
+		  const struct coproc_reg *r);
+
 #endif /* __ARM_KVM_COPROC_LOCAL_H__ */
-- 
1.8.3.4

^ permalink raw reply related

* [PATCH v2 06/10] ARM: KVM: fix handling of trapped 64bit coprocessor accesses
From: Marc Zyngier @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390402602-22777-1-git-send-email-marc.zyngier@arm.com>

Commit 240e99cbd00a (ARM: KVM: Fix 64-bit coprocessor handling)
changed the way we match the 64bit coprocessor access from
user space, but didn't update the trap handler for the same
set of registers.

The effect is that a trapped 64bit access is never matched, leading
to a fault being injected into the guest. This went unnoticed as we
didn;t really trap any 64bit register so far.

Placing the CRm field of the access into the CRn field of the matching
structure fixes the problem. Also update the debug feature to emit the
expected string in case of failing match.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 arch/arm/kvm/coproc.c | 4 ++--
 arch/arm/kvm/coproc.h | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index 78c0885..126c90d 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -443,7 +443,7 @@ int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
 {
 	struct coproc_params params;
 
-	params.CRm = (kvm_vcpu_get_hsr(vcpu) >> 1) & 0xf;
+	params.CRn = (kvm_vcpu_get_hsr(vcpu) >> 1) & 0xf;
 	params.Rt1 = (kvm_vcpu_get_hsr(vcpu) >> 5) & 0xf;
 	params.is_write = ((kvm_vcpu_get_hsr(vcpu) & 1) == 0);
 	params.is_64bit = true;
@@ -451,7 +451,7 @@ int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
 	params.Op1 = (kvm_vcpu_get_hsr(vcpu) >> 16) & 0xf;
 	params.Op2 = 0;
 	params.Rt2 = (kvm_vcpu_get_hsr(vcpu) >> 10) & 0xf;
-	params.CRn = 0;
+	params.CRm = 0;
 
 	return emulate_cp15(vcpu, &params);
 }
diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h
index 0461d5c..c5ad7ff 100644
--- a/arch/arm/kvm/coproc.h
+++ b/arch/arm/kvm/coproc.h
@@ -58,8 +58,8 @@ static inline void print_cp_instr(const struct coproc_params *p)
 {
 	/* Look, we even formatted it for you to paste into the table! */
 	if (p->is_64bit) {
-		kvm_pr_unimpl(" { CRm(%2lu), Op1(%2lu), is64, func_%s },\n",
-			      p->CRm, p->Op1, p->is_write ? "write" : "read");
+		kvm_pr_unimpl(" { CRm64(%2lu), Op1(%2lu), is64, func_%s },\n",
+			      p->CRn, p->Op1, p->is_write ? "write" : "read");
 	} else {
 		kvm_pr_unimpl(" { CRn(%2lu), CRm(%2lu), Op1(%2lu), Op2(%2lu), is32,"
 			      " func_%s },\n",
-- 
1.8.3.4

^ permalink raw reply related

* [PATCH v2 05/10] ARM: KVM: force cache clean on page fault when caches are off
From: Marc Zyngier @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390402602-22777-1-git-send-email-marc.zyngier@arm.com>

In order for the guest with caches off to observe data written
contained in a given page, we need to make sure that page is
committed to memory, and not just hanging in the cache (as
guest accesses are completely bypassing the cache until it
decides to enable it).

For this purpose, hook into the coherent_cache_guest_page
function and flush the region if the guest SCTLR
register doesn't show the MMU and caches as being enabled.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 arch/arm/include/asm/kvm_mmu.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
index cbab9ba..fa023e2 100644
--- a/arch/arm/include/asm/kvm_mmu.h
+++ b/arch/arm/include/asm/kvm_mmu.h
@@ -116,9 +116,14 @@ static inline void kvm_set_s2pmd_writable(pmd_t *pmd)
 
 struct kvm;
 
+#define kvm_flush_dcache_to_poc(a,l)	__cpuc_flush_dcache_area((a), (l))
+
 static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva,
 					     unsigned long size)
 {
+	if ((vcpu->arch.cp15[c1_SCTLR] & 0b101) != 0b101)
+		kvm_flush_dcache_to_poc((void *)hva, size);
+	
 	/*
 	 * If we are going to insert an instruction page and the icache is
 	 * either VIPT or PIPT, there is a potential problem where the host
@@ -139,8 +144,6 @@ static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva,
 	}
 }
 
-#define kvm_flush_dcache_to_poc(a,l)	__cpuc_flush_dcache_area((a), (l))
-
 void stage2_flush_vm(struct kvm *kvm);
 
 #endif	/* !__ASSEMBLY__ */
-- 
1.8.3.4

^ permalink raw reply related

* [PATCH v2 04/10] arm64: KVM: flush VM pages before letting the guest enable caches
From: Marc Zyngier @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390402602-22777-1-git-send-email-marc.zyngier@arm.com>

When the guest runs with caches disabled (like in an early boot
sequence, for example), all the writes are diectly going to RAM,
bypassing the caches altogether.

Once the MMU and caches are enabled, whatever sits in the cache
becomes suddently visible, which isn't what the guest expects.

A way to avoid this potential disaster is to invalidate the cache
when the MMU is being turned on. For this, we hook into the SCTLR_EL1
trapping code, and scan the stage-2 page tables, invalidating the
pages/sections that have already been mapped in.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
---
 arch/arm/include/asm/kvm_mmu.h   |  2 +
 arch/arm/kvm/mmu.c               | 83 ++++++++++++++++++++++++++++++++++++++++
 arch/arm64/include/asm/kvm_mmu.h |  1 +
 arch/arm64/kvm/sys_regs.c        |  5 ++-
 4 files changed, 90 insertions(+), 1 deletion(-)

diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
index f997b9e..cbab9ba 100644
--- a/arch/arm/include/asm/kvm_mmu.h
+++ b/arch/arm/include/asm/kvm_mmu.h
@@ -141,6 +141,8 @@ static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva,
 
 #define kvm_flush_dcache_to_poc(a,l)	__cpuc_flush_dcache_area((a), (l))
 
+void stage2_flush_vm(struct kvm *kvm);
+
 #endif	/* !__ASSEMBLY__ */
 
 #endif /* __ARM_KVM_MMU_H__ */
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 415fd63..52f8b7d 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -187,6 +187,89 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp,
 	}
 }
 
+void stage2_flush_ptes(struct kvm *kvm, pmd_t *pmd,
+		       unsigned long addr, unsigned long end)
+{
+	pte_t *pte;
+
+	pte = pte_offset_kernel(pmd, addr);
+	do {
+		if (!pte_none(*pte)) {
+			hva_t hva = gfn_to_hva(kvm, addr >> PAGE_SHIFT);
+			kvm_flush_dcache_to_poc((void*)hva, PAGE_SIZE);
+		}
+	} while(pte++, addr += PAGE_SIZE, addr != end);
+}
+
+void stage2_flush_pmds(struct kvm *kvm, pud_t *pud,
+		       unsigned long addr, unsigned long end)
+{
+	pmd_t *pmd;
+	unsigned long next;
+
+	pmd = pmd_offset(pud, addr);
+	do {
+		next = pmd_addr_end(addr, end);
+		if (!pmd_none(*pmd)) {
+			if (kvm_pmd_huge(*pmd)) {
+				hva_t hva = gfn_to_hva(kvm, addr >> PAGE_SHIFT);
+				kvm_flush_dcache_to_poc((void*)hva, PMD_SIZE);
+			} else {
+				stage2_flush_ptes(kvm, pmd, addr, next);
+			}
+		}
+	} while(pmd++, addr = next, addr != end);
+}
+
+void stage2_flush_puds(struct kvm *kvm, pgd_t *pgd,
+		       unsigned long addr, unsigned long end)
+{
+	pud_t *pud;
+	unsigned long next;
+
+	pud = pud_offset(pgd, addr);
+	do {
+		next = pud_addr_end(addr, end);
+		if (!pud_none(*pud)) {
+			if (pud_huge(*pud)) {
+				hva_t hva = gfn_to_hva(kvm, addr >> PAGE_SHIFT);
+				kvm_flush_dcache_to_poc((void*)hva, PUD_SIZE);
+			} else {
+				stage2_flush_pmds(kvm, pud, addr, next);
+			}
+		}
+	} while(pud++, addr = next, addr != end);
+}
+
+static void stage2_flush_memslot(struct kvm *kvm,
+				 struct kvm_memory_slot *memslot)
+{
+	unsigned long addr = memslot->base_gfn << PAGE_SHIFT;
+	unsigned long end = addr + PAGE_SIZE * memslot->npages;
+	unsigned long next;
+	pgd_t *pgd;
+
+	pgd = kvm->arch.pgd + pgd_index(addr);
+	do {
+		next = pgd_addr_end(addr, end);
+		stage2_flush_puds(kvm, pgd, addr, next);
+	} while(pgd++, addr = next, addr != end);
+}
+
+void stage2_flush_vm(struct kvm *kvm)
+{
+	struct kvm_memslots *slots;
+	struct kvm_memory_slot *memslot;
+
+	spin_lock(&kvm->mmu_lock);
+
+	slots = kvm_memslots(kvm);
+	kvm_for_each_memslot(memslot, slots)
+		stage2_flush_memslot(kvm, memslot);
+
+	spin_unlock(&kvm->mmu_lock);
+}
+
 /**
  * free_boot_hyp_pgd - free HYP boot page tables
  *
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 2232dd0..b7b2ca3 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -139,6 +139,7 @@ static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva,
 	}
 }
 
+void stage2_flush_vm(struct kvm *kvm);
 
 #endif /* __ASSEMBLY__ */
 #endif /* __ARM64_KVM_MMU_H__ */
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 1a4731b..3d27bb8 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -27,6 +27,7 @@
 #include <asm/kvm_host.h>
 #include <asm/kvm_emulate.h>
 #include <asm/kvm_coproc.h>
+#include <asm/kvm_mmu.h>
 #include <asm/cacheflush.h>
 #include <asm/cputype.h>
 #include <trace/events/kvm.h>
@@ -163,8 +164,10 @@ static bool access_sctlr(struct kvm_vcpu *vcpu,
 	else
 		vcpu_cp15(vcpu, r->reg) = val & 0xffffffffUL;
 
-	if ((val & (0b101)) == 0b101)	/* MMU+Caches enabled? */
+	if ((val & (0b101)) == 0b101) {	/* MMU+Caches enabled? */
 		vcpu->arch.hcr_el2 &= ~HCR_TVM;
+		stage2_flush_vm(vcpu->kvm);
+	}
 
 	return true;
 }
-- 
1.8.3.4

^ permalink raw reply related

* [PATCH v2 03/10] arm64: KVM: trap VM system registers until MMU and caches are ON
From: Marc Zyngier @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390402602-22777-1-git-send-email-marc.zyngier@arm.com>

In order to be able to detect the point where the guest enables
its MMU and caches, trap all the VM related system registers.

Once we see the guest enabling both the MMU and the caches, we
can go back to a saner mode of operation, which is to leave these
registers in complete control of the guest.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
---
 arch/arm64/include/asm/kvm_arm.h |  3 +-
 arch/arm64/include/asm/kvm_asm.h |  3 +-
 arch/arm64/kvm/sys_regs.c        | 99 +++++++++++++++++++++++++++++++++++-----
 3 files changed, 91 insertions(+), 14 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index c98ef47..fd0a651 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -62,6 +62,7 @@
  * RW:		64bit by default, can be overriden for 32bit VMs
  * TAC:		Trap ACTLR
  * TSC:		Trap SMC
+ * TVM:		Trap VM ops (until M+C set in SCTLR_EL1)
  * TSW:		Trap cache operations by set/way
  * TWE:		Trap WFE
  * TWI:		Trap WFI
@@ -74,7 +75,7 @@
  * SWIO:	Turn set/way invalidates into set/way clean+invalidate
  */
 #define HCR_GUEST_FLAGS (HCR_TSC | HCR_TSW | HCR_TWE | HCR_TWI | HCR_VM | \
-			 HCR_BSU_IS | HCR_FB | HCR_TAC | \
+			 HCR_TVM | HCR_BSU_IS | HCR_FB | HCR_TAC | \
 			 HCR_AMO | HCR_IMO | HCR_FMO | \
 			 HCR_SWIO | HCR_TIDCP | HCR_RW)
 #define HCR_VIRT_EXCP_MASK (HCR_VA | HCR_VI | HCR_VF)
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 3d796b4..89d7796 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -81,7 +81,8 @@
 #define c13_TID_URW	(TPIDR_EL0 * 2)	/* Thread ID, User R/W */
 #define c13_TID_URO	(TPIDRRO_EL0 * 2)/* Thread ID, User R/O */
 #define c13_TID_PRIV	(TPIDR_EL1 * 2)	/* Thread ID, Privileged */
-#define c10_AMAIR	(AMAIR_EL1 * 2)	/* Aux Memory Attr Indirection Reg */
+#define c10_AMAIR0	(AMAIR_EL1 * 2)	/* Aux Memory Attr Indirection Reg */
+#define c10_AMAIR1	(c10_AMAIR0 + 1)/* Aux Memory Attr Indirection Reg */
 #define c14_CNTKCTL	(CNTKCTL_EL1 * 2) /* Timer Control Register (PL1) */
 #define NR_CP15_REGS	(NR_SYS_REGS * 2)
 
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index f063750..1a4731b 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -121,6 +121,55 @@ done:
 }
 
 /*
+ * Generic accessor for VM registers. Only called as long as HCR_TVM
+ * is set.
+ */
+static bool access_vm_reg(struct kvm_vcpu *vcpu,
+			  const struct sys_reg_params *p,
+			  const struct sys_reg_desc *r)
+{
+	unsigned long val;
+
+	BUG_ON(!p->is_write);
+
+	val = *vcpu_reg(vcpu, p->Rt);
+	if (!p->is_aarch32) {
+		vcpu_sys_reg(vcpu, r->reg) = val;
+	} else {
+		vcpu_cp15(vcpu, r->reg) = val & 0xffffffffUL;
+		if (!p->is_32bit)
+			vcpu_cp15(vcpu, r->reg + 1) = val >> 32;
+	}
+	return true;
+}
+
+/*
+ * SCTLR_EL1 accessor. Only called as long as HCR_TVM is set.  If the
+ * guest enables the MMU, we stop trapping the VM sys_regs and leave
+ * it in complete control of the caches.
+ */
+static bool access_sctlr(struct kvm_vcpu *vcpu,
+			 const struct sys_reg_params *p,
+			 const struct sys_reg_desc *r)
+{
+	unsigned long val;
+
+	BUG_ON(!p->is_write);
+
+	val = *vcpu_reg(vcpu, p->Rt);
+
+	if (!p->is_aarch32)
+		vcpu_sys_reg(vcpu, r->reg) = val;
+	else
+		vcpu_cp15(vcpu, r->reg) = val & 0xffffffffUL;
+
+	if ((val & (0b101)) == 0b101)	/* MMU+Caches enabled? */
+		vcpu->arch.hcr_el2 &= ~HCR_TVM;
+
+	return true;
+}
+
+/*
  * We could trap ID_DFR0 and tell the guest we don't support performance
  * monitoring.  Unfortunately the patch to make the kernel check ID_DFR0 was
  * NAKed, so it will read the PMCR anyway.
@@ -185,32 +234,32 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 	  NULL, reset_mpidr, MPIDR_EL1 },
 	/* SCTLR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b000),
-	  NULL, reset_val, SCTLR_EL1, 0x00C50078 },
+	  access_sctlr, reset_val, SCTLR_EL1, 0x00C50078 },
 	/* CPACR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b010),
 	  NULL, reset_val, CPACR_EL1, 0 },
 	/* TTBR0_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b000),
-	  NULL, reset_unknown, TTBR0_EL1 },
+	  access_vm_reg, reset_unknown, TTBR0_EL1 },
 	/* TTBR1_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b001),
-	  NULL, reset_unknown, TTBR1_EL1 },
+	  access_vm_reg, reset_unknown, TTBR1_EL1 },
 	/* TCR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b010),
-	  NULL, reset_val, TCR_EL1, 0 },
+	  access_vm_reg, reset_val, TCR_EL1, 0 },
 
 	/* AFSR0_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0001), Op2(0b000),
-	  NULL, reset_unknown, AFSR0_EL1 },
+	  access_vm_reg, reset_unknown, AFSR0_EL1 },
 	/* AFSR1_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0001), Op2(0b001),
-	  NULL, reset_unknown, AFSR1_EL1 },
+	  access_vm_reg, reset_unknown, AFSR1_EL1 },
 	/* ESR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0010), Op2(0b000),
-	  NULL, reset_unknown, ESR_EL1 },
+	  access_vm_reg, reset_unknown, ESR_EL1 },
 	/* FAR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0110), CRm(0b0000), Op2(0b000),
-	  NULL, reset_unknown, FAR_EL1 },
+	  access_vm_reg, reset_unknown, FAR_EL1 },
 	/* PAR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b0111), CRm(0b0100), Op2(0b000),
 	  NULL, reset_unknown, PAR_EL1 },
@@ -224,17 +273,17 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 
 	/* MAIR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b1010), CRm(0b0010), Op2(0b000),
-	  NULL, reset_unknown, MAIR_EL1 },
+	  access_vm_reg, reset_unknown, MAIR_EL1 },
 	/* AMAIR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b1010), CRm(0b0011), Op2(0b000),
-	  NULL, reset_amair_el1, AMAIR_EL1 },
+	  access_vm_reg, reset_amair_el1, AMAIR_EL1 },
 
 	/* VBAR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b1100), CRm(0b0000), Op2(0b000),
 	  NULL, reset_val, VBAR_EL1, 0 },
 	/* CONTEXTIDR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b1101), CRm(0b0000), Op2(0b001),
-	  NULL, reset_val, CONTEXTIDR_EL1, 0 },
+	  access_vm_reg, reset_val, CONTEXTIDR_EL1, 0 },
 	/* TPIDR_EL1 */
 	{ Op0(0b11), Op1(0b000), CRn(0b1101), CRm(0b0000), Op2(0b100),
 	  NULL, reset_unknown, TPIDR_EL1 },
@@ -305,14 +354,32 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 	  NULL, reset_val, FPEXC32_EL2, 0x70 },
 };
 
-/* Trapped cp15 registers */
+/*
+ * Trapped cp15 registers. TTBR0/TTBR1 get a double encoding,
+ * depending on the way they are accessed (as a 32bit or a 64bit
+ * register).
+ */
 static const struct sys_reg_desc cp15_regs[] = {
+	{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
+	{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), access_sctlr, NULL, c1_SCTLR },
+	{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
+	{ Op1( 0), CRn( 2), CRm( 0), Op2( 1), access_vm_reg, NULL, c2_TTBR1 },
+	{ Op1( 0), CRn( 2), CRm( 0), Op2( 2), access_vm_reg, NULL, c2_TTBCR },
+	{ Op1( 0), CRn( 3), CRm( 0), Op2( 0), access_vm_reg, NULL, c3_DACR },
+	{ Op1( 0), CRn( 5), CRm( 0), Op2( 0), access_vm_reg, NULL, c5_DFSR },
+	{ Op1( 0), CRn( 5), CRm( 0), Op2( 1), access_vm_reg, NULL, c5_IFSR },
+	{ Op1( 0), CRn( 5), CRm( 1), Op2( 0), access_vm_reg, NULL, c5_ADFSR },
+	{ Op1( 0), CRn( 5), CRm( 1), Op2( 1), access_vm_reg, NULL, c5_AIFSR },
+	{ Op1( 0), CRn( 6), CRm( 0), Op2( 0), access_vm_reg, NULL, c6_DFAR },
+	{ Op1( 0), CRn( 6), CRm( 0), Op2( 2), access_vm_reg, NULL, c6_IFAR },
+
 	/*
 	 * DC{C,I,CI}SW operations:
 	 */
 	{ Op1( 0), CRn( 7), CRm( 6), Op2( 2), access_dcsw },
 	{ Op1( 0), CRn( 7), CRm(10), Op2( 2), access_dcsw },
 	{ Op1( 0), CRn( 7), CRm(14), Op2( 2), access_dcsw },
+
 	{ Op1( 0), CRn( 9), CRm(12), Op2( 0), pm_fake },
 	{ Op1( 0), CRn( 9), CRm(12), Op2( 1), pm_fake },
 	{ Op1( 0), CRn( 9), CRm(12), Op2( 2), pm_fake },
@@ -326,6 +393,14 @@ static const struct sys_reg_desc cp15_regs[] = {
 	{ Op1( 0), CRn( 9), CRm(14), Op2( 0), pm_fake },
 	{ Op1( 0), CRn( 9), CRm(14), Op2( 1), pm_fake },
 	{ Op1( 0), CRn( 9), CRm(14), Op2( 2), pm_fake },
+
+	{ Op1( 0), CRn(10), CRm( 2), Op2( 0), access_vm_reg, NULL, c10_PRRR },
+	{ Op1( 0), CRn(10), CRm( 2), Op2( 1), access_vm_reg, NULL, c10_NMRR },
+	{ Op1( 0), CRn(10), CRm( 3), Op2( 0), access_vm_reg, NULL, c10_AMAIR0 },
+	{ Op1( 0), CRn(10), CRm( 3), Op2( 1), access_vm_reg, NULL, c10_AMAIR1 },
+	{ Op1( 0), CRn(13), CRm( 0), Op2( 1), access_vm_reg, NULL, c13_CID },
+
+	{ Op1( 1), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR1 },
 };
 
 /* Target specific emulation tables */
-- 
1.8.3.4

^ permalink raw reply related

* [PATCH v2 02/10] arm64: KVM: allows discrimination of AArch32 sysreg access
From: Marc Zyngier @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390402602-22777-1-git-send-email-marc.zyngier@arm.com>

The current handling of AArch32 trapping is slightly less than
perfect, as it is not possible (from a handler point of view)
to distinguish it from an AArch64 access, nor to tell a 32bit
from a 64bit access either.

Fix this by introducing two additional flags:
- is_aarch32: true if the access was made in AArch32 mode
- is_32bit: true if is_aarch32 == true and a MCR/MRC instruction
  was used to perform the access (as opposed to MCRR/MRRC).

This allows a handler to cover all the possible conditions in which
a system register gets trapped.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 arch/arm64/kvm/sys_regs.c | 5 +++++
 arch/arm64/kvm/sys_regs.h | 2 ++
 2 files changed, 7 insertions(+)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 02e9d09..f063750 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -437,6 +437,8 @@ int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
 	u32 hsr = kvm_vcpu_get_hsr(vcpu);
 	int Rt2 = (hsr >> 10) & 0xf;
 
+	params.is_aarch32 = true;
+	params.is_32bit = false;
 	params.CRm = (hsr >> 1) & 0xf;
 	params.Rt = (hsr >> 5) & 0xf;
 	params.is_write = ((hsr & 1) == 0);
@@ -480,6 +482,8 @@ int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
 	struct sys_reg_params params;
 	u32 hsr = kvm_vcpu_get_hsr(vcpu);
 
+	params.is_aarch32 = true;
+	params.is_32bit = true;
 	params.CRm = (hsr >> 1) & 0xf;
 	params.Rt  = (hsr >> 5) & 0xf;
 	params.is_write = ((hsr & 1) == 0);
@@ -549,6 +553,7 @@ int kvm_handle_sys_reg(struct kvm_vcpu *vcpu, struct kvm_run *run)
 	struct sys_reg_params params;
 	unsigned long esr = kvm_vcpu_get_hsr(vcpu);
 
+	params.is_aarch32 = false;
 	params.Op0 = (esr >> 20) & 3;
 	params.Op1 = (esr >> 14) & 0x7;
 	params.CRn = (esr >> 10) & 0xf;
diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h
index d50d372..d411e25 100644
--- a/arch/arm64/kvm/sys_regs.h
+++ b/arch/arm64/kvm/sys_regs.h
@@ -30,6 +30,8 @@ struct sys_reg_params {
 	u8	Op2;
 	u8	Rt;
 	bool	is_write;
+	bool	is_aarch32;
+	bool	is_32bit;	/* Only valid if is_aarch32 is true */
 };
 
 struct sys_reg_desc {
-- 
1.8.3.4

^ permalink raw reply related

* [PATCH v2 01/10] arm64: KVM: force cache clean on page fault when caches are off
From: Marc Zyngier @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390402602-22777-1-git-send-email-marc.zyngier@arm.com>

In order for the guest with caches off to observe data written
contained in a given page, we need to make sure that page is
committed to memory, and not just hanging in the cache (as
guest accesses are completely bypassing the cache until it
decides to enable it).

For this purpose, hook into the coherent_icache_guest_page
function and flush the region if the guest SCTLR_EL1
register doesn't show the MMU  and caches as being enabled.
The function also get renamed to coherent_cache_guest_page.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
---
 arch/arm/include/asm/kvm_mmu.h   |  4 ++--
 arch/arm/kvm/mmu.c               |  4 ++--
 arch/arm64/include/asm/kvm_mmu.h | 11 +++++++----
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
index 77de4a4..f997b9e 100644
--- a/arch/arm/include/asm/kvm_mmu.h
+++ b/arch/arm/include/asm/kvm_mmu.h
@@ -116,8 +116,8 @@ static inline void kvm_set_s2pmd_writable(pmd_t *pmd)
 
 struct kvm;
 
-static inline void coherent_icache_guest_page(struct kvm *kvm, hva_t hva,
-					      unsigned long size)
+static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva,
+					     unsigned long size)
 {
 	/*
 	 * If we are going to insert an instruction page and the icache is
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 5809069..415fd63 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -713,7 +713,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 			kvm_set_s2pmd_writable(&new_pmd);
 			kvm_set_pfn_dirty(pfn);
 		}
-		coherent_icache_guest_page(kvm, hva & PMD_MASK, PMD_SIZE);
+		coherent_cache_guest_page(vcpu, hva & PMD_MASK, PMD_SIZE);
 		ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd);
 	} else {
 		pte_t new_pte = pfn_pte(pfn, PAGE_S2);
@@ -721,7 +721,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 			kvm_set_s2pte_writable(&new_pte);
 			kvm_set_pfn_dirty(pfn);
 		}
-		coherent_icache_guest_page(kvm, hva, PAGE_SIZE);
+		coherent_cache_guest_page(vcpu, hva, PAGE_SIZE);
 		ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, false);
 	}
 
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 680f74e..2232dd0 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -106,7 +106,6 @@ static inline bool kvm_is_write_fault(unsigned long esr)
 	return true;
 }
 
-static inline void kvm_clean_dcache_area(void *addr, size_t size) {}
 static inline void kvm_clean_pgd(pgd_t *pgd) {}
 static inline void kvm_clean_pmd_entry(pmd_t *pmd) {}
 static inline void kvm_clean_pte(pte_t *pte) {}
@@ -124,9 +123,14 @@ static inline void kvm_set_s2pmd_writable(pmd_t *pmd)
 
 struct kvm;
 
-static inline void coherent_icache_guest_page(struct kvm *kvm, hva_t hva,
-					      unsigned long size)
+#define kvm_flush_dcache_to_poc(a,l)	__flush_dcache_area((a), (l))
+
+static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva,
+					     unsigned long size)
 {
+	if ((vcpu_sys_reg(vcpu, SCTLR_EL1) & 0b101) != 0b101)
+		kvm_flush_dcache_to_poc((void *)hva, size);
+
 	if (!icache_is_aliasing()) {		/* PIPT */
 		flush_icache_range(hva, hva + size);
 	} else if (!icache_is_aivivt()) {	/* non ASID-tagged VIVT */
@@ -135,7 +139,6 @@ static inline void coherent_icache_guest_page(struct kvm *kvm, hva_t hva,
 	}
 }
 
-#define kvm_flush_dcache_to_poc(a,l)	__flush_dcache_area((a), (l))
 
 #endif /* __ASSEMBLY__ */
 #endif /* __ARM64_KVM_MMU_H__ */
-- 
1.8.3.4

^ permalink raw reply related

* [PATCH v2 00/10] arm/arm64: KVM: host cache maintainance when guest caches are off
From: Marc Zyngier @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel

When we run a guest with cache disabled, we don't flush the cache to
the Point of Coherency, hence possibly missing bits of data that have
been written in the cache, but have not yet reached memory.

We also have the opposite issue: when a guest enables its cache,
whatever sits in the cache is suddenly going to become visible,
shadowing whatever the guest has written into RAM.

There are several approaches to these issues:
- Using the DC bit when caches are off: this breaks guests assuming
  caches off while doing DMA operations. Bootloaders, for example.
  It also breaks the I-D coherency.
- Fetch the memory attributes on translation fault, and flush the
  cache while handling the fault. This relies on using the PAR_EL1
  register to obtain the Stage-1 memory attributes, and tends to be
  slow.
- Detecting the translation faults occuring with MMU off (and
  performing a cache clean), and trapping SCTLR_EL1 to detect the
  moment when the guest is turning its caches on (and performing a
  cache invalidation). Trapping of SCTLR_EL1 is then disabled to
  ensure the best performance.

This patch series implements the last solution, for both arm and
arm64. Tested on TC2 (ARMv7) and FVP model (ARMv8).

>From v1 (http://www.spinics.net/lists/kvm/msg99404.html):
- Fixed AArch32 VM handling on arm64 (Reported by Anup)
- Added ARMv7 support:
  * Fixed a couple of issues regarding handling of 64bit cp15 regs
  * Per-vcpu HCR
  * Switching of AMAIR0 and AMAIR1

Marc Zyngier (10):
  arm64: KVM: force cache clean on page fault when caches are off
  arm64: KVM: allows discrimination of AArch32 sysreg access
  arm64: KVM: trap VM system registers until MMU and caches are ON
  arm64: KVM: flush VM pages before letting the guest enable caches
  ARM: KVM: force cache clean on page fault when caches are off
  ARM: KVM: fix handling of trapped 64bit coprocessor accesses
  ARM: KVM: fix ordering of 64bit coprocessor accesses
  ARM: KVM: introduce per-vcpu HYP Configuration Register
  ARM: KVM: trap VM system registers until MMU and caches are ON
  ARM: KVM: add world-switch for AMAIR{0,1}

 arch/arm/include/asm/kvm_arm.h   |   4 +-
 arch/arm/include/asm/kvm_asm.h   |   4 +-
 arch/arm/include/asm/kvm_host.h  |   9 ++--
 arch/arm/include/asm/kvm_mmu.h   |  11 ++--
 arch/arm/kernel/asm-offsets.c    |   1 +
 arch/arm/kvm/coproc.c            |  95 +++++++++++++++++++++++++++-------
 arch/arm/kvm/coproc.h            |  14 +++--
 arch/arm/kvm/coproc_a15.c        |   2 +-
 arch/arm/kvm/coproc_a7.c         |   2 +-
 arch/arm/kvm/guest.c             |   1 +
 arch/arm/kvm/interrupts_head.S   |  21 +++++---
 arch/arm/kvm/mmu.c               |  87 ++++++++++++++++++++++++++++++-
 arch/arm64/include/asm/kvm_arm.h |   3 +-
 arch/arm64/include/asm/kvm_asm.h |   3 +-
 arch/arm64/include/asm/kvm_mmu.h |  12 +++--
 arch/arm64/kvm/sys_regs.c        | 107 ++++++++++++++++++++++++++++++++++-----
 arch/arm64/kvm/sys_regs.h        |   2 +
 17 files changed, 316 insertions(+), 62 deletions(-)

-- 
1.8.3.4

^ permalink raw reply

* [PATCH 18/20] clocksource / acpi: Add macro CLOCKSOURCE_ACPI_DECLARE
From: Arnd Bergmann @ 2014-01-22 14:56 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20140122114616.GB15591@e106331-lin.cambridge.arm.com>

On Wednesday 22 January 2014 11:46:16 Mark Rutland wrote:
> On Mon, Jan 20, 2014 at 09:08:32AM +0000, Hanjun Guo wrote:
> > On 2014-1-17 22:21, Arnd Bergmann wrote:
> > > On Friday 17 January 2014, Hanjun Guo wrote:
> > >>
> > >> From: Amit Daniel Kachhap <amit.daniel@samsung.com>
> > >>
> > >> This macro does the same job as CLOCKSOURCE_OF_DECLARE. The device
> > >> name from the ACPI timer table is matched with all the registered
> > >> timer controllers and matching initialisation routine is invoked.
> > > 
> > > I wouldn't anticipate this infrastructure to be required. Shouldn't all
> > > ARMv8 machines have an architected timer?
> > 
> > I not sure of this, could anyone can give some guidance? if only arch
> > timer is available for ARM64, this will make thing very simple.
> 
> All ARMv8 systems should have an architected timer.
> 
> However, they may also have other timers (e.g. global timers for use
> when CPUs are in low power states and their local architected timers
> aren't active).

But all other timers could be regular platform drivers I suppose. No
need for special infrastructure for those.

	Arnd

^ permalink raw reply

* [PATCH v6 0/3] AArch64: KGDB support
From: Vijay Kilari @ 2014-01-22 14:54 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <CALicx6tQu2O8o4pr-N8Xc=D-Y9kOMsFNsn6BLVDqRo0Pbay00Q@mail.gmail.com>

Hi Catalin,

On Sat, Jan 18, 2014 at 1:32 PM, Vijay Kilari <vijay.kilari@gmail.com> wrote:
> Hi Catalin,
>
> On Thu, Jan 16, 2014 at 7:15 PM, Catalin Marinas
> <catalin.marinas@arm.com> wrote:
>> On Thu, Dec 19, 2013 at 11:50:48AM +0000, vijay.kilari at gmail.com wrote:
>>> Vijaya Kumar K (3):
>>>   AArch64: KGDB: Add Basic KGDB support
>>>   AArch64: KGDB: Add step debugging support
>>>   KGDB: make kgdb_breakpoint() as noinline
>>
>> I gave them a try and now I have some doubts about your testing
>> methodology:
>>
>> 1. There is no HAVE_ARCH_KGDB anywhere in these patches, so
>> the code here isn't compiled.
>>
> OK, I will send a patch
>
>> 2. There are several compiler warnings that need to be addressed.
>>
>> 3. I enabled CONFIG_KGDB_TESTS and CONFIG_KGDB_TESTS_ON_BOOT and that's
>> what really scared me.
>>
>
> Are you refering to these warning?. I don't see any warning in the
> patched files. I will fix these.
>
> drivers/misc/kgdbts.c: In function 'check_single_step':
> drivers/misc/kgdbts.c:353:2: warning: format '%lx' expects argument of
> type 'long unsigned int', but argument 2 has type 'u64' [-Wformat]
> drivers/misc/kgdbts.c:379:3: warning: format '%lx' expects argument of
> type 'long unsigned int', but argument 2 has type 'u64' [-Wformat]
> drivers/misc/kgdbts.c: In function 'emul_sstep_put':
> drivers/misc/kgdbts.c:494:3: warning: format '%lx' expects argument of
> type 'long unsigned int', but argument 2 has type 'u64' [-Wformat]
> kernel/debug/debug_core.c: In function 'kgdb_cpu_enter':
> kernel/debug/debug_core.c:498:4: warning: value computed is not used
> [-Wunused-value]
> kernel/debug/debug_core.c:513:5: warning: value computed is not used
> [-Wunused-value]
>

  The last warnings in kernel/debug/debug_core.c is due to
atomic_xchg(&kgdb_active, cpu);
returns value which is not captured as it is not useful. Though we capture
to dummy variable again it is raises unused variable warning

>> Please address these before we can consider the patches for merging.
>>
>> --
>> Catalin

^ permalink raw reply

* [PATCHv6 4/7] staging: imx-drm: Use de-active and pixelclk-active display-timings.
From: Dan Carpenter @ 2014-01-22 14:45 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390398511-8041-4-git-send-email-denis@eukrea.com>

On Wed, Jan 22, 2014 at 02:48:28PM +0100, Denis Carikli wrote:
> If de-active and/or pixelclk-active properties were set in the
> display-timings DT node, they were not used.
> 
> Instead the data-enable and the pixel data clock polarity
> were hardcoded.
> 
> This change is needed for making the eukrea-cpuimx51
>   QVGA display work.
> 
> Cc: David Airlie <airlied@linux.ie>
> Cc: Eric B?nard <eric@eukrea.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Philipp Zabel <p.zabel@pengutronix.de>
> Cc: Sascha Hauer <kernel@pengutronix.de>
> Cc: Shawn Guo <shawn.guo@linaro.org>
> Cc: dri-devel at lists.freedesktop.org
> Cc: driverdev-devel at linuxdriverproject.org
> Cc: linux-arm-kernel at lists.infradead.org

These CC blocks are massive...  What's the point of them?

>  	if (np) {
>  		struct drm_display_mode *mode = drm_mode_create(connector->dev);
> +		struct device_node *timings_np;
> +		struct device_node *mode_np;
> +		u32 val;
> +
>  		of_get_drm_display_mode(np, &imxpd->mode, 0);
> +
> +		timings_np = of_get_child_by_name(np, "display-timings");
> +		if (timings_np) {
> +			/* get the display mode node */
> +			mode_np = of_parse_phandle(timings_np,
> +						   "native-mode", 0);
> +			if (!mode_np)
> +				mode_np = of_get_next_child(timings_np, NULL);
> +
> +			/* set de-active to 1 if not set */
> +			of_property_read_u32(mode_np, "de-active", &val);
> +			if (val) {

If of_property_read_u32() fails then val is uninitialized.

regards,
dan carpenter

^ permalink raw reply

* [PATCH v7 6/6] arm64: KGDB: Add KGDB config
From: vijay.kilari at gmail.com @ 2014-01-22 14:42 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390401773-12100-1-git-send-email-vijay.kilari@gmail.com>

From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>

Add HAVE_ARCH_KGDB for arm64 Kconfig

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
---
 arch/arm64/Kconfig |    1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 6d4dd22..c7a08e0 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -28,6 +28,7 @@ config ARM64
 	select HAVE_HW_BREAKPOINT if PERF_EVENTS
 	select HAVE_MEMBLOCK
 	select HAVE_PERF_EVENTS
+	select HAVE_ARCH_KGDB
 	select IRQ_DOMAIN
 	select MODULES_USE_ELF_RELA
 	select NO_BOOTMEM
-- 
1.7.9.5

^ permalink raw reply related

* [PATCH v7 5/6] misc: debug: remove compilation warnings
From: vijay.kilari at gmail.com @ 2014-01-22 14:42 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390401773-12100-1-git-send-email-vijay.kilari@gmail.com>

From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>

Resolve following compiler warnings
warning: format '%lx' expects argument of type 'long unsigned int',
but argument 2 has type 'u64' [-Wformat]

tested for warnings on arm32 & arm64

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
---
 drivers/misc/kgdbts.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c
index 36f5d52..78e10b2 100644
--- a/drivers/misc/kgdbts.c
+++ b/drivers/misc/kgdbts.c
@@ -350,8 +350,8 @@ static int check_single_step(char *put_str, char *arg)
 	kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
 		 NUMREGBYTES);
 	gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
-	v2printk("Singlestep stopped at IP: %lx\n",
-		   instruction_pointer(&kgdbts_regs));
+	v2printk("Singlestep stopped at IP: %llx\n",
+		   (unsigned long long)instruction_pointer(&kgdbts_regs));
 
 	if (sstep_thread_id != cont_thread_id) {
 		/*
@@ -376,8 +376,8 @@ static int check_single_step(char *put_str, char *arg)
 continue_test:
 	matched_id = 0;
 	if (instruction_pointer(&kgdbts_regs) == addr) {
-		eprintk("kgdbts: SingleStep failed at %lx\n",
-			   instruction_pointer(&kgdbts_regs));
+		eprintk("kgdbts: SingleStep failed at %llx\n",
+			(unsigned long long)instruction_pointer(&kgdbts_regs));
 		return 1;
 	}
 
@@ -491,8 +491,8 @@ static int emul_sstep_put(char *put_str, char *arg)
 		kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
 			 NUMREGBYTES);
 		gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
-		v2printk("Stopped at IP: %lx\n",
-			 instruction_pointer(&kgdbts_regs));
+		v2printk("Stopped at IP: %llx\n",
+			 (unsigned long long)instruction_pointer(&kgdbts_regs));
 		/* Want to stop at IP + break instruction size by default */
 		sstep_addr = cont_addr + BREAK_INSTR_SIZE;
 		break;
-- 
1.7.9.5

^ permalink raw reply related

* [PATCH RESEND] cpufreq: exynos: Fix build error of no type of module_init
From: Viresh Kumar @ 2014-01-22 14:42 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390400476-22951-1-git-send-email-k.kozlowski@samsung.com>

On 22 January 2014 19:51, Krzysztof Kozlowski <k.kozlowski@samsung.com> wrote:
> Add missing include to fix build error:
> drivers/cpufreq/exynos-cpufreq.c:292:1: warning: data definition has no type or storage class [enabled by default]
> drivers/cpufreq/exynos-cpufreq.c:292:1: error: type defaults to ?int? in declaration of ?module_init? [-Werror=implicit-int]
> drivers/cpufreq/exynos-cpufreq.c:292:1: warning: parameter names (without types) in function declaration [enabled by default]
> drivers/cpufreq/exynos-cpufreq.c:292:1: warning: data definition has no type or storage class [enabled by default]
> drivers/cpufreq/exynos-cpufreq.c:292:1: error: type defaults to ?int? in declaration of ?module_exit? [-Werror=implicit-int]
> drivers/cpufreq/exynos-cpufreq.c:292:1: warning: parameter names (without types) in function declaration [enabled by default]
> drivers/cpufreq/exynos-cpufreq.c:292:1: warning: ?exynos_cpufreq_platdrv_init? defined but not used [-Wunused-function]
> cc1: some warnings being treated as errors
> make[2]: *** [drivers/cpufreq/exynos-cpufreq.o] Error 1
> make[1]: *** [drivers/cpufreq] Error 2
>
> Build error happens on gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5)
> and was introduced by commit d568b6f71df1 (cpufreq: exynos: Convert
> exynos-cpufreq to platform driver).
>
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> Cc: Lukasz Majewski <l.majewski@samsung.com>
> Cc: Tomasz Figa <t.figa@samsung.com>
> Cc: Kyungmin Park <kyungmin.park@samsung.com>
> ---
>  drivers/cpufreq/exynos-cpufreq.c |    1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/cpufreq/exynos-cpufreq.c b/drivers/cpufreq/exynos-cpufreq.c
> index fcd2914d081a..fa54c2b88dd7 100644
> --- a/drivers/cpufreq/exynos-cpufreq.c
> +++ b/drivers/cpufreq/exynos-cpufreq.c
> @@ -17,6 +17,7 @@
>  #include <linux/regulator/consumer.h>
>  #include <linux/cpufreq.h>
>  #include <linux/suspend.h>
> +#include <linux/module.h>
>  #include <linux/platform_device.h>

I am surprised how that patch went through then? And nothing was
reported by kbuild for it..

^ permalink raw reply

* [PATCH v7 4/6] KGDB: make kgdb_breakpoint() as noinline
From: vijay.kilari at gmail.com @ 2014-01-22 14:42 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390401773-12100-1-git-send-email-vijay.kilari@gmail.com>

From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>

The function kgdb_breakpoint() sets up break point at
compile time by calling arch_kgdb_breakpoint();
Though this call is surrounded by wmb() barrier,
the compile can still re-order the break point,
because this scheduling barrier is not a code motion
barrier in gcc.

Making kgdb_breakpoint() as noinline solves this problem
of code reording around break point instruction and also
avoids problem of being called as inline function from
other places

More details about discussion on this can be found here
http://comments.gmane.org/gmane.linux.ports.arm.kernel/269732

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
---
 kernel/debug/debug_core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 7d2f35e..cf04798 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -1034,7 +1034,7 @@ int dbg_io_get_char(void)
  * otherwise as a quick means to stop program execution and "break" into
  * the debugger.
  */
-void kgdb_breakpoint(void)
+noinline void kgdb_breakpoint(void)
 {
 	atomic_inc(&kgdb_setting_breakpoint);
 	wmb(); /* Sync point before breakpoint */
-- 
1.7.9.5

^ permalink raw reply related

* [PATCH v7 3/6] arm64: KGDB: Add step debugging support
From: vijay.kilari at gmail.com @ 2014-01-22 14:42 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390401773-12100-1-git-send-email-vijay.kilari@gmail.com>

From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>

Add KGDB software step debugging support for EL1 debug
in AArch64 mode.

KGDB registers step debug handler with debug monitor.
On receiving 'step' command from GDB tool, target enables
software step debugging and step address is updated in ELR.

Software Step debugging is disabled when 'continue' command
is received

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/kernel/kgdb.c |   64 ++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 56 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c
index 4b7a569..75c9cf1 100644
--- a/arch/arm64/kernel/kgdb.c
+++ b/arch/arm64/kernel/kgdb.c
@@ -137,13 +137,26 @@ void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
 
 static int compiled_break;
 
+static void kgdb_arch_update_addr(struct pt_regs *regs,
+				char *remcom_in_buffer)
+{
+	unsigned long addr;
+	char *ptr;
+
+	ptr = &remcom_in_buffer[1];
+	if (kgdb_hex2long(&ptr, &addr))
+		kgdb_arch_set_pc(regs, addr);
+	else if (compiled_break == 1)
+		kgdb_arch_set_pc(regs, regs->pc + 4);
+
+	compiled_break = 0;
+}
+
 int kgdb_arch_handle_exception(int exception_vector, int signo,
 			       int err_code, char *remcom_in_buffer,
 			       char *remcom_out_buffer,
 			       struct pt_regs *linux_regs)
 {
-	unsigned long addr;
-	char *ptr;
 	int err;
 
 	switch (remcom_in_buffer[0]) {
@@ -162,13 +175,36 @@ int kgdb_arch_handle_exception(int exception_vector, int signo,
 		 * to the next instruction else we will just breakpoint
 		 * over and over again.
 		 */
-		ptr = &remcom_in_buffer[1];
-		if (kgdb_hex2long(&ptr, &addr))
-			kgdb_arch_set_pc(linux_regs, addr);
-		else if (compiled_break == 1)
-			kgdb_arch_set_pc(linux_regs, linux_regs->pc + 4);
+		kgdb_arch_update_addr(linux_regs, remcom_in_buffer);
+		atomic_set(&kgdb_cpu_doing_single_step, -1);
+		kgdb_single_step =  0;
+
+		/*
+		 * Received continue command, disable single step
+		 */
+		if (kernel_active_single_step())
+			kernel_disable_single_step();
+
+		err = 0;
+		break;
+	case 's':
+		/*
+		 * Update step address value with address passed
+		 * with step packet.
+		 * On debug exception return PC is copied to ELR
+		 * So just update PC.
+		 * If no step address is passed, resume from the address
+		 * pointed by PC. Do not update PC
+		 */
+		kgdb_arch_update_addr(linux_regs, remcom_in_buffer);
+		atomic_set(&kgdb_cpu_doing_single_step, raw_smp_processor_id());
+		kgdb_single_step =  1;
 
-		compiled_break = 0;
+		/*
+		 * Enable single step handling
+		 */
+		if (!kernel_active_single_step())
+			kernel_enable_single_step(linux_regs);
 		err = 0;
 		break;
 	default:
@@ -191,6 +227,12 @@ static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int esr)
 	return 0;
 }
 
+static int kgdb_step_brk_fn(struct pt_regs *regs, unsigned int esr)
+{
+	kgdb_handle_exception(1, SIGTRAP, 0, regs);
+	return 0;
+}
+
 static struct break_hook kgdb_brkpt_hook = {
 	.esr_mask	= 0xffffffff,
 	.esr_val	= DBG_ESR_VAL_BRK(KGDB_DYN_DGB_BRK_IMM),
@@ -203,6 +245,10 @@ static struct break_hook kgdb_compiled_brkpt_hook = {
 	.fn		= kgdb_compiled_brk_fn
 };
 
+static struct step_hook kgdb_step_hook = {
+	.fn		= kgdb_step_brk_fn
+};
+
 static void kgdb_call_nmi_hook(void *ignored)
 {
 	kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs());
@@ -259,6 +305,7 @@ int kgdb_arch_init(void)
 
 	register_break_hook(&kgdb_brkpt_hook);
 	register_break_hook(&kgdb_compiled_brkpt_hook);
+	register_step_hook(&kgdb_step_hook);
 	return 0;
 }
 
@@ -271,6 +318,7 @@ void kgdb_arch_exit(void)
 {
 	unregister_break_hook(&kgdb_brkpt_hook);
 	unregister_break_hook(&kgdb_compiled_brkpt_hook);
+	unregister_step_hook(&kgdb_step_hook);
 	unregister_die_notifier(&kgdb_notifier);
 }
 
-- 
1.7.9.5

^ permalink raw reply related

* [PATCH v7 2/6] arm64: KGDB: Add Basic KGDB support
From: vijay.kilari at gmail.com @ 2014-01-22 14:42 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390401773-12100-1-git-send-email-vijay.kilari@gmail.com>

From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>

Add KGDB debug support for kernel debugging.
With this patch, basic KGDB debugging is possible.GDB register
layout is updated and GDB tool can establish connection with
target and can set/clear breakpoints.

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/include/asm/debug-monitors.h |   47 +++++
 arch/arm64/include/asm/kgdb.h           |   84 +++++++++
 arch/arm64/kernel/Makefile              |    1 +
 arch/arm64/kernel/kgdb.c                |  288 +++++++++++++++++++++++++++++++
 4 files changed, 420 insertions(+)

diff --git a/arch/arm64/include/asm/debug-monitors.h b/arch/arm64/include/asm/debug-monitors.h
index bc48880..8d8b417 100644
--- a/arch/arm64/include/asm/debug-monitors.h
+++ b/arch/arm64/include/asm/debug-monitors.h
@@ -26,6 +26,53 @@
 #define DBG_ESR_EVT_HWWP	0x2
 #define DBG_ESR_EVT_BRK		0x6
 
+/*
+ * Break point instruction encoding
+ */
+#define BREAK_INSTR_SIZE		4
+
+/*
+ * ESR values expected for dynamic and compile time BRK instruction
+ */
+#define DBG_ESR_VAL_BRK(x)	(0xf2000000 | ((x) & 0xfffff))
+
+/*
+ * #imm16 values used for BRK instruction generation
+ * Allowed values for kgbd are 0x400 - 0x7ff
+ * 0x400: for dynamic BRK instruction
+ * 0x401: for compile time BRK instruction
+ */
+#define KGDB_DYN_DGB_BRK_IMM		0x400
+#define KDBG_COMPILED_DBG_BRK_IMM	0x401
+
+/*
+ * BRK instruction encoding
+ * The #imm16 value should be placed at bits[20:5] within BRK ins
+ */
+#define AARCH64_BREAK_MON	0xd4200000
+
+/*
+ * Extract byte from BRK instruction
+ */
+#define KGDB_DYN_DGB_BRK_INS_BYTE(x) \
+	((((AARCH64_BREAK_MON) & 0xffe0001f) >> (x * 8)) & 0xff)
+
+/*
+ * Extract byte from BRK #imm16
+ */
+#define KGBD_DYN_DGB_BRK_IMM_BYTE(x) \
+	(((((KGDB_DYN_DGB_BRK_IMM) & 0xffff) << 5) >> (x * 8)) & 0xff)
+
+#define KGDB_DYN_DGB_BRK_BYTE(x) \
+	(KGDB_DYN_DGB_BRK_INS_BYTE(x) | KGBD_DYN_DGB_BRK_IMM_BYTE(x))
+
+#define  KGDB_DYN_BRK_INS_BYTE0  KGDB_DYN_DGB_BRK_BYTE(0)
+#define  KGDB_DYN_BRK_INS_BYTE1  KGDB_DYN_DGB_BRK_BYTE(1)
+#define  KGDB_DYN_BRK_INS_BYTE2  KGDB_DYN_DGB_BRK_BYTE(2)
+#define  KGDB_DYN_BRK_INS_BYTE3  KGDB_DYN_DGB_BRK_BYTE(3)
+
+#define CACHE_FLUSH_IS_SAFE		1
+
 enum debug_el {
 	DBG_ACTIVE_EL0 = 0,
 	DBG_ACTIVE_EL1,
diff --git a/arch/arm64/include/asm/kgdb.h b/arch/arm64/include/asm/kgdb.h
new file mode 100644
index 0000000..3c8aafc
--- /dev/null
+++ b/arch/arm64/include/asm/kgdb.h
@@ -0,0 +1,84 @@
+/*
+ * AArch64 KGDB support
+ *
+ * Based on arch/arm/include/kgdb.h
+ *
+ * Copyright (C) 2013 Cavium Inc.
+ * Author: Vijaya Kumar K <vijaya.kumar@caviumnetworks.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __ARM_KGDB_H
+#define __ARM_KGDB_H
+
+#include <linux/ptrace.h>
+#include <asm/debug-monitors.h>
+
+#ifndef	__ASSEMBLY__
+
+static inline void arch_kgdb_breakpoint(void)
+{
+	asm ("brk %0" : : "I" (KDBG_COMPILED_DBG_BRK_IMM));
+}
+
+extern void kgdb_handle_bus_error(void);
+extern int kgdb_fault_expected;
+
+#endif /* !__ASSEMBLY__ */
+
+/*
+ * gdb is expecting the following registers layout.
+ *
+ * General purpose regs:
+ *     r0-r30: 64 bit
+ *     sp,pc : 64 bit
+ *     pstate  : 64 bit
+ *     Total: 34
+ * FPU regs:
+ *     f0-f31: 128 bit
+ *     Total: 32
+ * Extra regs
+ *     fpsr & fpcr: 32 bit
+ *     Total: 2
+ *
+ */
+
+#define _GP_REGS		34
+#define _FP_REGS		32
+#define _EXTRA_REGS		2
+/*
+ * general purpose registers size in bytes.
+ * pstate is only 4 bytes. subtract 4 bytes
+ */
+#define GP_REG_BYTES		(_GP_REGS * 8)
+#define DBG_MAX_REG_NUM		(_GP_REGS + _FP_REGS + _EXTRA_REGS)
+
+/*
+ * Size of I/O buffer for gdb packet.
+ * considering to hold all register contents, size is set
+ */
+
+#define BUFMAX			2048
+
+/*
+ * Number of bytes required for gdb_regs buffer.
+ * _GP_REGS: 8 bytes, _FP_REGS: 16 bytes and _EXTRA_REGS: 4 bytes each
+ * GDB fails to connect for size beyond this with error
+ * "'g' packet reply is too long"
+ */
+
+#define NUMREGBYTES	((_GP_REGS * 8) + (_FP_REGS * 16) + \
+			(_EXTRA_REGS * 4))
+
+#endif /* __ASM_KGDB_H */
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 5ba2fd4..b9b87fa 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -18,6 +18,7 @@ arm64-obj-$(CONFIG_SMP)			+= smp.o smp_spin_table.o
 arm64-obj-$(CONFIG_HW_PERF_EVENTS)	+= perf_event.o
 arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o
 arm64-obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
+arm64-obj-$(CONFIG_KGDB)		+= kgdb.o
 
 obj-y					+= $(arm64-obj-y) vdso/
 obj-m					+= $(arm64-obj-m)
diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c
new file mode 100644
index 0000000..4b7a569
--- /dev/null
+++ b/arch/arm64/kernel/kgdb.c
@@ -0,0 +1,288 @@
+/*
+ * AArch64 KGDB support
+ *
+ * Based on arch/arm/kernel/kgdb.c
+ *
+ * Copyright (C) 2013 Cavium Inc.
+ * Author: Vijaya Kumar K <vijaya.kumar@caviumnetworks.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/irq.h>
+#include <linux/kdebug.h>
+#include <linux/kgdb.h>
+#include <asm/traps.h>
+
+struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
+	{ "x0", 8, offsetof(struct pt_regs, regs[0])},
+	{ "x1", 8, offsetof(struct pt_regs, regs[1])},
+	{ "x2", 8, offsetof(struct pt_regs, regs[2])},
+	{ "x3", 8, offsetof(struct pt_regs, regs[3])},
+	{ "x4", 8, offsetof(struct pt_regs, regs[4])},
+	{ "x5", 8, offsetof(struct pt_regs, regs[5])},
+	{ "x6", 8, offsetof(struct pt_regs, regs[6])},
+	{ "x7", 8, offsetof(struct pt_regs, regs[7])},
+	{ "x8", 8, offsetof(struct pt_regs, regs[8])},
+	{ "x9", 8, offsetof(struct pt_regs, regs[9])},
+	{ "x10", 8, offsetof(struct pt_regs, regs[10])},
+	{ "x11", 8, offsetof(struct pt_regs, regs[11])},
+	{ "x12", 8, offsetof(struct pt_regs, regs[12])},
+	{ "x13", 8, offsetof(struct pt_regs, regs[13])},
+	{ "x14", 8, offsetof(struct pt_regs, regs[14])},
+	{ "x15", 8, offsetof(struct pt_regs, regs[15])},
+	{ "x16", 8, offsetof(struct pt_regs, regs[16])},
+	{ "x17", 8, offsetof(struct pt_regs, regs[17])},
+	{ "x18", 8, offsetof(struct pt_regs, regs[18])},
+	{ "x19", 8, offsetof(struct pt_regs, regs[19])},
+	{ "x20", 8, offsetof(struct pt_regs, regs[20])},
+	{ "x21", 8, offsetof(struct pt_regs, regs[21])},
+	{ "x22", 8, offsetof(struct pt_regs, regs[22])},
+	{ "x23", 8, offsetof(struct pt_regs, regs[23])},
+	{ "x24", 8, offsetof(struct pt_regs, regs[24])},
+	{ "x25", 8, offsetof(struct pt_regs, regs[25])},
+	{ "x26", 8, offsetof(struct pt_regs, regs[26])},
+	{ "x27", 8, offsetof(struct pt_regs, regs[27])},
+	{ "x28", 8, offsetof(struct pt_regs, regs[28])},
+	{ "x29", 8, offsetof(struct pt_regs, regs[29])},
+	{ "x30", 8, offsetof(struct pt_regs, regs[30])},
+	{ "sp", 8, offsetof(struct pt_regs, sp)},
+	{ "pc", 8, offsetof(struct pt_regs, pc)},
+	{ "pstate", 8, offsetof(struct pt_regs, pstate)},
+	{ "v0", 16, -1 },
+	{ "v1", 16, -1 },
+	{ "v2", 16, -1 },
+	{ "v3", 16, -1 },
+	{ "v4", 16, -1 },
+	{ "v5", 16, -1 },
+	{ "v6", 16, -1 },
+	{ "v7", 16, -1 },
+	{ "v8", 16, -1 },
+	{ "v9", 16, -1 },
+	{ "v10", 16, -1 },
+	{ "v11", 16, -1 },
+	{ "v12", 16, -1 },
+	{ "v13", 16, -1 },
+	{ "v14", 16, -1 },
+	{ "v15", 16, -1 },
+	{ "v16", 16, -1 },
+	{ "v17", 16, -1 },
+	{ "v18", 16, -1 },
+	{ "v19", 16, -1 },
+	{ "v20", 16, -1 },
+	{ "v21", 16, -1 },
+	{ "v22", 16, -1 },
+	{ "v23", 16, -1 },
+	{ "v24", 16, -1 },
+	{ "v25", 16, -1 },
+	{ "v26", 16, -1 },
+	{ "v27", 16, -1 },
+	{ "v28", 16, -1 },
+	{ "v29", 16, -1 },
+	{ "v30", 16, -1 },
+	{ "v31", 16, -1 },
+	{ "fpsr", 4, -1 },
+	{ "fpcr", 4, -1 },
+};
+
+char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return NULL;
+
+	if (dbg_reg_def[regno].offset != -1)
+		memcpy(mem, (void *)regs + dbg_reg_def[regno].offset,
+		       dbg_reg_def[regno].size);
+	else
+		memset(mem, 0, dbg_reg_def[regno].size);
+	return dbg_reg_def[regno].name;
+}
+
+int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return -EINVAL;
+
+	if (dbg_reg_def[regno].offset != -1)
+		memcpy((void *)regs + dbg_reg_def[regno].offset, mem,
+		       dbg_reg_def[regno].size);
+	return 0;
+}
+
+void
+sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *task)
+{
+	struct pt_regs *thread_regs;
+
+	/* Initialize to zero */
+	memset((char *)gdb_regs, 0, NUMREGBYTES);
+	thread_regs = task_pt_regs(task);
+	memcpy((void *)gdb_regs, (void *)thread_regs->regs, GP_REG_BYTES);
+}
+
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
+{
+	regs->pc = pc;
+}
+
+static int compiled_break;
+
+int kgdb_arch_handle_exception(int exception_vector, int signo,
+			       int err_code, char *remcom_in_buffer,
+			       char *remcom_out_buffer,
+			       struct pt_regs *linux_regs)
+{
+	unsigned long addr;
+	char *ptr;
+	int err;
+
+	switch (remcom_in_buffer[0]) {
+	case 'D':
+	case 'k':
+		/*
+		 * Packet D (Detach), k (kill). No special handling
+		 * is required here. Handle same as c packet.
+		 */
+	case 'c':
+		/*
+		 * Packet c (Continue) to continue executing.
+		 * Set pc to required address.
+		 * Try to read optional parameter and set pc.
+		 * If this was a compiled breakpoint, we need to move
+		 * to the next instruction else we will just breakpoint
+		 * over and over again.
+		 */
+		ptr = &remcom_in_buffer[1];
+		if (kgdb_hex2long(&ptr, &addr))
+			kgdb_arch_set_pc(linux_regs, addr);
+		else if (compiled_break == 1)
+			kgdb_arch_set_pc(linux_regs, linux_regs->pc + 4);
+
+		compiled_break = 0;
+		err = 0;
+		break;
+	default:
+		err = -1;
+	}
+	return err;
+}
+
+static int kgdb_brk_fn(struct pt_regs *regs, unsigned int esr)
+{
+	kgdb_handle_exception(1, SIGTRAP, 0, regs);
+	return 0;
+}
+
+static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int esr)
+{
+	compiled_break = 1;
+	kgdb_handle_exception(1, SIGTRAP, 0, regs);
+
+	return 0;
+}
+
+static struct break_hook kgdb_brkpt_hook = {
+	.esr_mask	= 0xffffffff,
+	.esr_val	= DBG_ESR_VAL_BRK(KGDB_DYN_DGB_BRK_IMM),
+	.fn		= kgdb_brk_fn
+};
+
+static struct break_hook kgdb_compiled_brkpt_hook = {
+	.esr_mask	= 0xffffffff,
+	.esr_val	= DBG_ESR_VAL_BRK(KDBG_COMPILED_DBG_BRK_IMM),
+	.fn		= kgdb_compiled_brk_fn
+};
+
+static void kgdb_call_nmi_hook(void *ignored)
+{
+	kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs());
+}
+
+void kgdb_roundup_cpus(unsigned long flags)
+{
+	local_irq_enable();
+	smp_call_function(kgdb_call_nmi_hook, NULL, 0);
+	local_irq_disable();
+}
+
+static int __kgdb_notify(struct die_args *args, unsigned long cmd)
+{
+	struct pt_regs *regs = args->regs;
+
+	if (kgdb_handle_exception(1, args->signr, cmd, regs))
+		return NOTIFY_DONE;
+	return NOTIFY_STOP;
+}
+
+static int
+kgdb_notify(struct notifier_block *self, unsigned long cmd, void *ptr)
+{
+	unsigned long flags;
+	int ret;
+
+	local_irq_save(flags);
+	ret = __kgdb_notify(ptr, cmd);
+	local_irq_restore(flags);
+
+	return ret;
+}
+
+static struct notifier_block kgdb_notifier = {
+	.notifier_call	= kgdb_notify,
+	/*
+	 * Want to be lowest priority
+	 */
+	.priority	= -INT_MAX,
+};
+
+/*
+ * kgdb_arch_init - Perform any architecture specific initalization.
+ * This function will handle the initalization of any architecture
+ * specific callbacks.
+ */
+int kgdb_arch_init(void)
+{
+	int ret = register_die_notifier(&kgdb_notifier);
+
+	if (ret != 0)
+		return ret;
+
+	register_break_hook(&kgdb_brkpt_hook);
+	register_break_hook(&kgdb_compiled_brkpt_hook);
+	return 0;
+}
+
+/*
+ * kgdb_arch_exit - Perform any architecture specific uninitalization.
+ * This function will handle the uninitalization of any architecture
+ * specific callbacks, for dynamic registration and unregistration.
+ */
+void kgdb_arch_exit(void)
+{
+	unregister_break_hook(&kgdb_brkpt_hook);
+	unregister_break_hook(&kgdb_compiled_brkpt_hook);
+	unregister_die_notifier(&kgdb_notifier);
+}
+
+/*
+ * ARM instructions are always in LE.
+ * Break instruction is encoded in LE format
+ */
+struct kgdb_arch arch_kgdb_ops = {
+	.gdb_bpt_instr = {
+		KGDB_DYN_BRK_INS_BYTE0,
+		KGDB_DYN_BRK_INS_BYTE1,
+		KGDB_DYN_BRK_INS_BYTE2,
+		KGDB_DYN_BRK_INS_BYTE3,
+	}
+};
-- 
1.7.9.5

^ permalink raw reply related

* [PATCH 1/6] arm64: Add macros to manage processor debug state
From: vijay.kilari at gmail.com @ 2014-01-22 14:42 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390401773-12100-1-git-send-email-vijay.kilari@gmail.com>

From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>

Add macros to enable and disable to manage PSTATE.D
for debugging. The macros local_dbg_save and local_dbg_restore
are moved to irqflags.h file

KGDB boot tests fail because of PSTATE.D is masked.
unmask it for debugging support

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
---
 arch/arm64/include/asm/debug-monitors.h |   18 ++----------------
 arch/arm64/include/asm/irqflags.h       |   22 ++++++++++++++++++++++
 arch/arm64/kernel/debug-monitors.c      |    3 ++-
 3 files changed, 26 insertions(+), 17 deletions(-)

diff --git a/arch/arm64/include/asm/debug-monitors.h b/arch/arm64/include/asm/debug-monitors.h
index 6231479..bc48880 100644
--- a/arch/arm64/include/asm/debug-monitors.h
+++ b/arch/arm64/include/asm/debug-monitors.h
@@ -43,22 +43,8 @@ enum debug_el {
 #ifndef __ASSEMBLY__
 struct task_struct;
 
-#define local_dbg_save(flags)							\
-	do {									\
-		typecheck(unsigned long, flags);				\
-		asm volatile(							\
-		"mrs	%0, daif			// local_dbg_save\n"	\
-		"msr	daifset, #8"						\
-		: "=r" (flags) : : "memory");					\
-	} while (0)
-
-#define local_dbg_restore(flags)						\
-	do {									\
-		typecheck(unsigned long, flags);				\
-		asm volatile(							\
-		"msr	daif, %0			// local_dbg_restore\n"	\
-		: : "r" (flags) : "memory");					\
-	} while (0)
+#define local_dbg_enable()	asm("msr	daifclr, #8" : : : "memory")
+#define local_dbg_disable()	asm("msr	daifset, #8" : : : "memory")
 
 #define DBG_ARCH_ID_RESERVED	0	/* In case of ptrace ABI updates. */
 
diff --git a/arch/arm64/include/asm/irqflags.h b/arch/arm64/include/asm/irqflags.h
index b2fcfbc..f163b11 100644
--- a/arch/arm64/include/asm/irqflags.h
+++ b/arch/arm64/include/asm/irqflags.h
@@ -90,5 +90,27 @@ static inline int arch_irqs_disabled_flags(unsigned long flags)
 	return flags & PSR_I_BIT;
 }
 
+/*
+ * save and restore debug state
+ */
+static inline unsigned long local_dbg_save(void)
+{
+	unsigned long flags;
+	asm volatile(
+		"mrs	%0, daif		// local_dbg_save"
+		"msr	daifset, #8"
+		: "=r" (flags) : : "memory");
+	return flags;
+}
+
+static inline void local_dbg_restore(unsigned long flags)
+{
+	asm volatile(
+		"msr	daif, %0	// local_dbg_restore"
+		:
+		: "r" (flags)
+		: "memory");
+}
+
 #endif
 #endif
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index 23586bd..774ad04 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -51,7 +51,7 @@ u8 debug_monitors_arch(void)
 static void mdscr_write(u32 mdscr)
 {
 	unsigned long flags;
-	local_dbg_save(flags);
+	flags = local_dbg_save();
 	asm volatile("msr mdscr_el1, %0" :: "r" (mdscr));
 	local_dbg_restore(flags);
 }
@@ -138,6 +138,7 @@ static void clear_os_lock(void *unused)
 {
 	asm volatile("msr oslar_el1, %0" : : "r" (0));
 	isb();
+	local_dbg_enable();
 }
 
 static int os_lock_notify(struct notifier_block *self,
-- 
1.7.9.5

^ permalink raw reply related

* [PATCH v7 0/6] arm64: KGDB Support
From: vijay.kilari at gmail.com @ 2014-01-22 14:42 UTC (permalink / raw)
  To: linux-arm-kernel

From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>

Based on the step-handler and break-handler hooks patch from
Sandeepa, KGDB debugging support is added for EL1
debug in AArch64 mode.

In first patch, PSTATE.D is set correctly

In second patch,register layout is updated to be inline with GDB tool.
Basic GDB connection, break point set/clear and info commands
are supported except step/next debugging

With second patch, step/next debugging support is added, where in
pc is updated to point to the instruction to be stepped and
stopped.

With third patch, the compile time breakpoint instruction
reordering is fixed by making kgbd_breakpoint() as noinline

Tested with ARM64 simulator

v7:
 - Changes made to set PSTATE.D properly
 - Performed KGDB boot tests
 - Fixed compilation warnings in driver/misc/kgbdts.c

Results:

kgdb boot test:

  [32927.237895] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
  [32927.266066] kgdb: Registered I/O driver kgdbts.
  [32927.266419] kgdb: Waiting for connection from remote gdb...
  [32927.268598] kgdbts:RUN plant and detach test
  [32927.270683] kgdbts:RUN sw breakpoint test
  [32927.287659] kgdbts:RUN bad memory access test
  [32927.290322] kgdbts:RUN singlestep test 1000 iterations
  [32927.330342] kgdbts:RUN singlestep [0/1000]
  [32931.286356] kgdbts:RUN singlestep [100/1000]
  [32935.242536] kgdbts:RUN singlestep [200/1000]
  [32939.205392] kgdbts:RUN singlestep [300/1000]
  [32943.169522] kgdbts:RUN singlestep [400/1000]
  [32947.231868] kgdbts:RUN singlestep [500/1000]
  [32951.188008] kgdbts:RUN singlestep [600/1000]
  [32955.332243] kgdbts:RUN singlestep [700/1000]
  [32959.467109] kgdbts:RUN singlestep [800/1000]
  [32963.430888] kgdbts:RUN singlestep [900/1000]
  [32967.346992] kgdbts:RUN do_fork for 100 breakpoints

kgdb test from sysfs:

  ~ # echo V1F1000 > /sys/module/kgdbts/parameters/kgdbts
  [33231.554237] kgdb: Registered I/O driver kgdbts.
  [33231.554677] kgdbts:RUN plant and detach test
  [33231.557072] kgdbts:RUN sw breakpoint test
  [33231.576980] kgdbts:RUN bad memory access test
  [33231.580022] kgdbts:RUN singlestep test 1000 iterations
  [33231.627056] kgdbts:RUN singlestep [0/1000]
  [33235.954027] kgdbts:RUN singlestep [100/1000]
  [33240.429086] kgdbts:RUN singlestep [200/1000]
  [33244.687118] kgdbts:RUN singlestep [300/1000]
  [33248.945191] kgdbts:RUN singlestep [400/1000]
  [33253.203751] kgdbts:RUN singlestep [500/1000]
  [33257.462019] kgdbts:RUN singlestep [600/1000]
  [33261.817809] kgdbts:RUN singlestep [700/1000]
  [33266.081268] kgdbts:RUN singlestep [800/1000]
  [33270.339813] kgdbts:RUN singlestep [900/1000]
  [33274.712404] kgdbts:RUN do_fork for 1000 breakpoints
  ~ #

v6:
 - Change pstate register to 8 bytes to make endian nuetral.
   Use GDB below GDB patch to display pstate in Big endian mode.
   https://sourceware.org/ml/gdb-patches/2013-12/msg00720.html
   Thanks to Andrew.

v5:
 - Updated BRK #imm16 value to 0x400 & 0x401 as per recommendation
   as per Marcus recommendataion
   http://patchwork.ozlabs.org/patch/290801/
 - Rebased to 3.13 AArch64 kernel

v4:
 - Updated kgdb_single_step and kgdb_cpu_doing_single_step
   variables properly based on gdb state

v3:
 - Rebased to v4 version of Sandeepa Prabhu's patch (patch 1)
 - Made dynamic break point instruction encoding generic
 - Made ESR value encoding generic for dynamic and compile break point
 - Used memcpy and memset to copy register contents to gdb buffer
 - Fixed reordering of break point instruction by compiler with
   patch 3
 - Rebased against AAach64 upstream kernel

v2:
 - Moved break instruction encoding to debug-monitors.h file
 - Fixed endianess of compile break instruction encoding
 - Updated I/O buffer sizes
 - Updated register buffer size
 - Remove changes to debug_exception handler in entry.S for
 - ELR update and step debugging with update pc instead of ELR
 - Rebased against AArch64 upstream kernel

v1:
 - Initial patch-set

Vijaya Kumar K (6):
  arm64: Add macros to manage processor debug state
  arm64: KGDB: Add Basic KGDB support
  arm64: KGDB: Add step debugging support
  KGDB: make kgdb_breakpoint() as noinline
  misc: debug: remove compilation warnings
  arm64: KGDB: Add KGDB config

 arch/arm64/Kconfig                      |    1 +
 arch/arm64/include/asm/debug-monitors.h |   65 ++++--
 arch/arm64/include/asm/irqflags.h       |   22 ++
 arch/arm64/include/asm/kgdb.h           |   84 ++++++++
 arch/arm64/kernel/Makefile              |    1 +
 arch/arm64/kernel/debug-monitors.c      |    3 +-
 arch/arm64/kernel/kgdb.c                |  336 +++++++++++++++++++++++++++++++
 drivers/misc/kgdbts.c                   |   12 +-
 kernel/debug/debug_core.c               |    2 +-
 9 files changed, 502 insertions(+), 24 deletions(-)
 create mode 100644 arch/arm64/include/asm/kgdb.h
 create mode 100644 arch/arm64/kernel/kgdb.c

-- 
1.7.9.5

^ permalink raw reply

* [PATCH] watchdog: Add sp805_wdt depends on ARM64
From: Viresh Kumar @ 2014-01-22 14:40 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <1390394643-25443-1-git-send-email-naresh.bhat@linaro.org>

On 22 January 2014 18:14,  <naresh.bhat@linaro.org> wrote:
> From: Naresh Bhat <naresh.bhat@linaro.org>
>
> Add sp805_wdt depends on ARM64.
>
> Signed-off-by: Naresh Bhat <naresh.bhat@linaro.org>
> ---
>  drivers/watchdog/Kconfig |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 5be6e91..2385124 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -109,7 +109,7 @@ config WM8350_WATCHDOG
>
>  config ARM_SP805_WATCHDOG
>         tristate "ARM SP805 Watchdog"
> -       depends on ARM && ARM_AMBA
> +       depends on (ARM || ARM64) && ARM_AMBA
>         select WATCHDOG_CORE
>         help
>           ARM Primecell SP805 Watchdog timer. This will reboot your system when

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

^ permalink raw reply

* [PATCH RFC 08/26] dmaengine: omap-dma: consolidate setup of CCR
From: Santosh Shilimkar @ 2014-01-22 14:39 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20140122141905.GQ27282@n2100.arm.linux.org.uk>

On Wednesday 22 January 2014 09:19 AM, Russell King - ARM Linux wrote:
> On Wed, Jan 22, 2014 at 06:25:57PM +0530, Sricharan R wrote:
>> Setting up of DMA_DST_SYNC_PREFETCH is missing after this ?
> 
> I'm not looking for the DMA engine driver to be a 100% reimplementation
> of the legacy driver.  Rather than supporting the entire set of features
> which the legacy driver did, and have many of them simply not used, the
> approach I'm taking here is to only support what is necessary for the
> drivers we have in mainline - and what fits the DMA engine interfaces.
> 
+1 on the approach.

> There is no point inventing new DMA engine interfaces for features for
> which we have no users in mainline kernel - to try to do that will be
> quite rightfully thrown out by the DMA engine maintainers.
> 
> Here's the total number of references/definitions of DMA_DST_SYNC_PREFETCH
> in the mainline kernel:
> 
> arch/arm/plat-omap/dma.c:               if (src_or_dst_synch == OMAP_DMA_DST_SYNC_PREFETCH) {
> include/linux/omap-dma.h:#define OMAP_DMA_DST_SYNC_PREFETCH     0x02
> 
> Hence, this feature is unused at present.
> 
I thought the crypto was using the prefetch feature but it isn't. 

Regards,
Santosh

^ permalink raw reply

* [PATCH 18/20] clocksource / acpi: Add macro CLOCKSOURCE_ACPI_DECLARE
From: Linus Walleij @ 2014-01-22 14:38 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20140122114537.GA15591@e106331-lin.cambridge.arm.com>

On Wed, Jan 22, 2014 at 12:45 PM, Mark Rutland <mark.rutland@arm.com> wrote:
> On Wed, Jan 22, 2014 at 08:26:50AM +0000, Linus Walleij wrote:

>> This hammers down the world to compile one binary for ACPI
>> and one binary for device tree. Maybe that's fine, I don't know.
>
> How does it do that?

Bah it doesn't I misread the patch. Forget that comment.

Yours,
Linus Walleij

^ permalink raw reply

* [PATCH RESEND] cpufreq: exynos: Fix build error of no type of module_init
From: Krzysztof Kozlowski @ 2014-01-22 14:21 UTC (permalink / raw)
  To: linux-arm-kernel

Add missing include to fix build error:
drivers/cpufreq/exynos-cpufreq.c:292:1: warning: data definition has no type or storage class [enabled by default]
drivers/cpufreq/exynos-cpufreq.c:292:1: error: type defaults to ?int? in declaration of ?module_init? [-Werror=implicit-int]
drivers/cpufreq/exynos-cpufreq.c:292:1: warning: parameter names (without types) in function declaration [enabled by default]
drivers/cpufreq/exynos-cpufreq.c:292:1: warning: data definition has no type or storage class [enabled by default]
drivers/cpufreq/exynos-cpufreq.c:292:1: error: type defaults to ?int? in declaration of ?module_exit? [-Werror=implicit-int]
drivers/cpufreq/exynos-cpufreq.c:292:1: warning: parameter names (without types) in function declaration [enabled by default]
drivers/cpufreq/exynos-cpufreq.c:292:1: warning: ?exynos_cpufreq_platdrv_init? defined but not used [-Wunused-function]
cc1: some warnings being treated as errors
make[2]: *** [drivers/cpufreq/exynos-cpufreq.o] Error 1
make[1]: *** [drivers/cpufreq] Error 2

Build error happens on gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5)
and was introduced by commit d568b6f71df1 (cpufreq: exynos: Convert
exynos-cpufreq to platform driver).

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Lukasz Majewski <l.majewski@samsung.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
---
 drivers/cpufreq/exynos-cpufreq.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/cpufreq/exynos-cpufreq.c b/drivers/cpufreq/exynos-cpufreq.c
index fcd2914d081a..fa54c2b88dd7 100644
--- a/drivers/cpufreq/exynos-cpufreq.c
+++ b/drivers/cpufreq/exynos-cpufreq.c
@@ -17,6 +17,7 @@
 #include <linux/regulator/consumer.h>
 #include <linux/cpufreq.h>
 #include <linux/suspend.h>
+#include <linux/module.h>
 #include <linux/platform_device.h>
 
 #include <plat/cpu.h>
-- 
1.7.9.5

^ permalink raw reply related

* [PATCH RFC 08/26] dmaengine: omap-dma: consolidate setup of CCR
From: Russell King - ARM Linux @ 2014-01-22 14:19 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <52DFBFDD.8040506@ti.com>

On Wed, Jan 22, 2014 at 06:25:57PM +0530, Sricharan R wrote:
> Setting up of DMA_DST_SYNC_PREFETCH is missing after this ?

I'm not looking for the DMA engine driver to be a 100% reimplementation
of the legacy driver.  Rather than supporting the entire set of features
which the legacy driver did, and have many of them simply not used, the
approach I'm taking here is to only support what is necessary for the
drivers we have in mainline - and what fits the DMA engine interfaces.

There is no point inventing new DMA engine interfaces for features for
which we have no users in mainline kernel - to try to do that will be
quite rightfully thrown out by the DMA engine maintainers.

Here's the total number of references/definitions of DMA_DST_SYNC_PREFETCH
in the mainline kernel:

arch/arm/plat-omap/dma.c:               if (src_or_dst_synch == OMAP_DMA_DST_SYNC_PREFETCH) {
include/linux/omap-dma.h:#define OMAP_DMA_DST_SYNC_PREFETCH     0x02

Hence, this feature is unused at present.

-- 
FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up.  Estimation
in database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad.
Estimate before purchase was "up to 13.2Mbit".

^ permalink raw reply


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