powerpc: Add kexec/kdump support for ppc32

Hi Dale,

Just a nit ...

arch/powerpc/kernel/machine_kexec.c int overlaps_crashkernel(unsigned long start, unsigned long size) · line 134

Quoted 4 lines · On Thu, 22 Nov 2007 08:45:17 -0700 Dale Farnsworth <[email protected]> wrote:

arch/powerpc/kernel/machine_kexec.c +4 -0

+static struct property crashk_base_prop = {
+	.name = "linux,crashkernel-base",
+	.length = sizeof(unsigned long),
+	.value = &crashk_res.start, };

arch/powerpc/platforms/85xx/mpc85xx_mds.c +5 -0

@@ -202,6 +203,11 @@ define_machine(mpc85xx_mds) {
 	.init_IRQ	= mpc85xx_mds_pic_init,
 	.get_irq	= mpic_get_irq,
 	.restart	= fsl_rstcr_restart,
+#ifdef CONFIG_KEXEC
+	.machine_kexec_prepare = default_machine_kexec_prepare,
+	.machine_kexec = default_machine_kexec,
+	.machine_crash_shutdown	= default_machine_crash_shutdown,
+#endif

index 8b642ab..db0e749 100644

arch/powerpc/kernel/misc_32.S +5 -0

@@ -816,6 +816,75 @@ relocate_new_kernel:
 	/* r4 = reboot_code_buffer */
 	/* r5 = start_address      */
 
+#ifdef CONFIG_E500
+	/*
+	 * Since we can't turn off the MMU, we must create an identity
+	 * map for kernel low memory.  We start by invalidating the
+	 * TLB entries we don't need.

Quoted 12 lines

index 8b642ab..db0e749 100644

arch/powerpc/kernel/misc_32.S +5 -0

@@ -816,6 +816,75 @@ relocate_new_kernel:
 	/* r4 = reboot_code_buffer */
 	/* r5 = start_address      */
 
+#ifdef CONFIG_E500
+	/*
+	 * Since we can't turn off the MMU, we must create an identity
+	 * map for kernel low memory.  We start by invalidating the
+	 * TLB entries we don't need.

arch/powerpc/kernel/misc_32.S relocate_new_kernel: · line 833

Quoted 10 lines

arch/powerpc/kernel/misc_32.S +10 -0

+	 *
+	 * First, invalidate the TLB0 entries
+	 */
+	li	r6, 0x04
+	tlbivax	0, r6
+#ifdef CONFIG_SMP
+	tlbsync
+#endif
+	msync
+

This is really E500 specific or should it be CONFIG_FSL_BOOKE ?

Ben.

Add the ability to build a ppc_85xx kernel to run at a physical address of 32MB.

Signed-off-by Dale Farnsworth <[email protected]>

---

arch/powerpc/Kconfig                 |    2 +-
arch/powerpc/kernel/head_fsl_booke.S |   23 ++++++++++++++++++-----
arch/powerpc/mm/fsl_booke_mmu.c      |    6 +++---
3 files changed, 22 insertions(+), 9 deletions(-)

arch/powerpc/Kconfig +0 -0

index 805b4d1..d405298 100644
@@ -253,7 +253,7 @@ config KEXEC
 

config CRASH_DUMP
bool "Build a kdump crash kernel (EXPERIMENTAL)"

arch/powerpc/Kconfig +1 -1

-	depends on PPC_MULTIPLATFORM && EXPERIMENTAL
+	depends on (PPC_MULTIPLATFORM || PPC_85xx) && EXPERIMENTAL

help
Build a kernel suitable for use as a kdump capture kernel. The kernel will be linked at a different address than normal, and

arch/powerpc/kernel/head_fsl_booke.S +0 -0

index 4b98227..1c9685f 100644

arch/powerpc/kernel/head_fsl_booke.S +13 -5

+
 /* As with the other PowerPC ports, it is expected that when code
 * execution begins here, the following registers contain valid, yet
 * optional, information:

@@ -75,6 +81,7 @@ _ENTRY(_start);
 * boot loader and load a single entry in TLB1[0] to map the
 * first 16M of kernel memory.  Any boot info passed from the
 * bootloader needs to live in this first 16M.
+ * Note that for crash (kdump) kernels, the first 64M is mapped.
 *
 * Requirement on bootloader:
 *  - The page we're executing in needs to reside in TLB1 and

@@ -167,7 +174,7 @@ skpinv:	addi	r6,r6,1				/* Increment */
 	mtspr	SPRN_MAS0,r7
 	tlbre
 
-	/* Just modify the entry ID and EPN for the temp mapping */
+	/* Just modify the entry ID, EPN and RPN for the temp mapping */
 	lis	r7,0x1000	/* Set MAS0(TLBSEL) = 1 */
 	rlwimi	r7,r5,16,4,15	/* Setup MAS0 = TLBSEL | ESEL(r5) */
 	mtspr	SPRN_MAS0,r7

@@ -177,9 +184,12 @@ skpinv:	addi	r6,r6,1				/* Increment */
 	ori	r6,r6,(MAS1_TSIZE(BOOKE_PAGESZ_4K))@l
 	mtspr	SPRN_MAS1,r6
 	mfspr	r6,SPRN_MAS2
-	li	r7,0		/* temp EPN = 0 */
+	lis	r7,PHYSICAL_START@h
 	rlwimi	r7,r6,0,20,31
 	mtspr	SPRN_MAS2,r7
+	mfspr	r6,SPRN_MAS3
+	rlwimi	r7,r6,0,20,31
+	mtspr	SPRN_MAS3,r7
 	tlbwe
 
 	xori	r6,r4,1

@@ -222,11 +232,11 @@ skpinv:	addi	r6,r6,1				/* Increment */
 	lis	r6,0x1000		/* Set MAS0(TLBSEL) = TLB1(1), ESEL = 0 */
 	mtspr	SPRN_MAS0,r6
 	lis	r6,(MAS1_VALID|MAS1_IPROT)@h
-	ori	r6,r6,(MAS1_TSIZE(BOOKE_PAGESZ_16M))@l
+	ori	r6,r6,(MAS1_TSIZE(INITIAL_BOOKE_PAGESZ))@l
 	mtspr	SPRN_MAS1,r6
 	li	r7,0
-	lis	r6,KERNELBASE@h
-	ori	r6,r6,KERNELBASE@l
+	lis	r6,PAGE_OFFSET@h
+	ori	r6,r6,PAGE_OFFSET@l
 	rlwimi	r6,r7,0,20,31
 	mtspr	SPRN_MAS2,r6
 	li	r7,(MAS3_SX|MAS3_SW|MAS3_SR)

@@ -234,6 +244,9 @@ skpinv:	addi	r6,r6,1				/* Increment */
 	tlbwe
 
 /* 7. Jump to KERNELBASE mapping */
+	lis	r6,KERNELBASE@h
+	ori	r6,r6,KERNELBASE@l
+	rlwimi	r6,r7,0,20,31
 	lis	r7,MSR_KERNEL@h
 	ori	r7,r7,MSR_KERNEL@l
 	bl	1f			/* Find our address */

arch/powerpc/mm/fsl_booke_mmu.c +3 -3

index 17139da..c93a966 100644
@@ -165,15 +165,15 @@ void invalidate_tlbcam_entry(int index)
 void __init cam_mapin_ram(unsigned long cam0, unsigned long cam1,
 		unsigned long cam2)
 {
-	settlbcam(0, KERNELBASE, PPC_MEMSTART, cam0, _PAGE_KERNEL, 0);
+	settlbcam(0, PAGE_OFFSET, PPC_MEMSTART, cam0, _PAGE_KERNEL, 0);
 	tlbcam_index++;
 	if (cam1) {
 		tlbcam_index++;
-		settlbcam(1, KERNELBASE+cam0, PPC_MEMSTART+cam0, cam1,  
 _PAGE_KERNEL, 0);
+		settlbcam(1, PAGE_OFFSET+cam0, PPC_MEMSTART+cam0, cam1,  
 _PAGE_KERNEL, 0);
 	}
 	if (cam2) {
 		tlbcam_index++;
-		settlbcam(2, KERNELBASE+cam0+cam1, PPC_MEMSTART+cam0+cam1, cam2,  
 _PAGE_KERNEL, 0);
+		settlbcam(2, PAGE_OFFSET+cam0+cam1, PPC_MEMSTART+cam0+cam1, cam2,  

_PAGE_KERNEL, 0);
	}
}

Quoted 32 lines · Dale Farnsworth

Add the ability to build a ppc_85xx kernel to run at a physical address of 32MB.

Signed-off-by Dale Farnsworth <[email protected]>

---

arch/powerpc/Kconfig                 |    2 +-
arch/powerpc/kernel/head_fsl_booke.S |   23 ++++++++++++++++++-----
arch/powerpc/mm/fsl_booke_mmu.c      |    6 +++---
3 files changed, 22 insertions(+), 9 deletions(-)

arch/powerpc/Kconfig +0 -0

index 805b4d1..d405298 100644
@@ -253,7 +253,7 @@ config KEXEC
 

config CRASH_DUMP
bool "Build a kdump crash kernel (EXPERIMENTAL)"

arch/powerpc/Kconfig +1 -1

-	depends on PPC_MULTIPLATFORM && EXPERIMENTAL
+	depends on (PPC_MULTIPLATFORM || PPC_85xx) && EXPERIMENTAL

help
Build a kernel suitable for use as a kdump capture kernel. The kernel will be linked at a different address than normal, and

arch/powerpc/ renamed from arch/powerpc/kernel/head_fsl_booke.S +0 -0

kernel/head_fsl_booke.S
index 4b98227..1c9685f 100644

arch/powerpc/kernel/head_fsl_booke.S +0 -0

@@ -41,6 +41,12 @@
 #include <asm/asm-offsets.h>
 #include "head_booke.h"
 

arch/powerpc/kernel/head_fsl_booke.S line 48

Quoted 5 lines

arch/powerpc/kernel/head_fsl_booke.S +5 -0

+#ifdef CONFIG_CRASH_DUMP
+#define INITIAL_BOOKE_PAGESZ (BOOKE_PAGESZ_64M)
+#else
+#define INITIAL_BOOKE_PAGESZ (BOOKE_PAGESZ_16M)
+#endif

I'm ok with bumping the first page to 64M in all cases.

The rest looks good. Does this mean we can boot a e500 kernel at a non-zero physical address? (can we run or is the non-zero phy just for a short period of init time).

Quoted 34 lines · Kumar Gala

Quoted 32 lines · Dale Farnsworth

Add the ability to build a ppc_85xx kernel to run at a physical address of 32MB.

Signed-off-by Dale Farnsworth <[email protected]>

---

arch/powerpc/Kconfig                 |    2 +-
arch/powerpc/kernel/head_fsl_booke.S |   23 ++++++++++++++++++-----
arch/powerpc/mm/fsl_booke_mmu.c      |    6 +++---
3 files changed, 22 insertions(+), 9 deletions(-)

arch/powerpc/Kconfig +0 -0

index 805b4d1..d405298 100644
@@ -253,7 +253,7 @@ config KEXEC
 

config CRASH_DUMP
bool "Build a kdump crash kernel (EXPERIMENTAL)"

arch/powerpc/Kconfig +1 -1

-	depends on PPC_MULTIPLATFORM && EXPERIMENTAL
+	depends on (PPC_MULTIPLATFORM || PPC_85xx) && EXPERIMENTAL

help
Build a kernel suitable for use as a kdump capture kernel. The kernel will be linked at a different address than normal, and

arch/powerpc/ renamed from arch/powerpc/kernel/head_fsl_booke.S +0 -0

kernel/head_fsl_booke.S
index 4b98227..1c9685f 100644

arch/powerpc/kernel/head_fsl_booke.S +0 -0

@@ -41,6 +41,12 @@
 #include <asm/asm-offsets.h>
 #include "head_booke.h"
 

Quoted 7 lines

arch/powerpc/kernel/head_fsl_booke.S line 48

Quoted 5 lines

arch/powerpc/kernel/head_fsl_booke.S +5 -0

+#ifdef CONFIG_CRASH_DUMP
+#define INITIAL_BOOKE_PAGESZ (BOOKE_PAGESZ_64M)
+#else
+#define INITIAL_BOOKE_PAGESZ (BOOKE_PAGESZ_16M)
+#endif

I'm ok with bumping the first page to 64M in all cases.

OK, I'll make that change in the next rev. Thanks.

<snip>

Quoted 3 lines

The rest looks good. Does this mean we can boot a e500 kernel at a non-zero physical address? (can we run or is the non-zero phy just for a short period of init time).

Yes, with this series of patches, we can boot and run with a classic ppc or e500 kernel at 32MB physical (0xc2000000 virtual). Note that on classic, we still need memory at phys 0 for the exception vectors. On e500 IIRC, we don't use the vectors at phys 0, but we still write the trampoline vectors there. I just didn't bother making that conditional.

I'll post an updated series soon, with hopes of getting it into 2.6.25

Quoted 43 lines · Dale Farnsworth

Quoted 41 lines · Kumar Gala

Quoted 29 lines · Dale Farnsworth

Add the ability to build a ppc_85xx kernel to run at a physical address of 32MB.

Signed-off-by Dale Farnsworth <[email protected]>

---

arch/powerpc/Kconfig                 |    2 +-
arch/powerpc/kernel/head_fsl_booke.S |   23 ++++++++++++++++++-----
arch/powerpc/mm/fsl_booke_mmu.c      |    6 +++---
3 files changed, 22 insertions(+), 9 deletions(-)

arch/powerpc/Kconfig +0 -0

index 805b4d1..d405298 100644
@@ -253,7 +253,7 @@ config KEXEC
 

config CRASH_DUMP
bool "Build a kdump crash kernel (EXPERIMENTAL)"

arch/powerpc/Kconfig +1 -1

-	depends on PPC_MULTIPLATFORM && EXPERIMENTAL
+	depends on (PPC_MULTIPLATFORM || PPC_85xx) && EXPERIMENTAL

help
Build a kernel suitable for use as a kdump capture kernel. The kernel will be linked at a different address than normal, and

arch/powerpc/ renamed from arch/powerpc/kernel/head_fsl_booke.S +0 -0

kernel/head_fsl_booke.S
index 4b98227..1c9685f 100644

arch/powerpc/kernel/head_fsl_booke.S line 48

Quoted 8 lines

arch/powerpc/kernel/head_fsl_booke.S +5 -0

@@ -41,6 +41,12 @@
 #include <asm/asm-offsets.h>
 #include "head_booke.h"
 
+#ifdef CONFIG_CRASH_DUMP
+#define INITIAL_BOOKE_PAGESZ (BOOKE_PAGESZ_64M)
+#else
+#define INITIAL_BOOKE_PAGESZ (BOOKE_PAGESZ_16M)
+#endif

I'm ok with bumping the first page to 64M in all cases.

Quoted 1 line

OK, I'll make that change in the next rev. Thanks.

I'm about to commit a version of this patch, why did you need to bump to 64M?

Quoted 6 lines

<snip>

Quoted 3 lines

The rest looks good. Does this mean we can boot a e500 kernel at a non-zero physical address? (can we run or is the non-zero phy just for a short period of init time).

Quoted 6 lines

Yes, with this series of patches, we can boot and run with a classic ppc or e500 kernel at 32MB physical (0xc2000000 virtual). Note that on classic, we still need memory at phys 0 for the exception vectors. On e500 IIRC, we don't use the vectors at phys 0, but we still write the trampoline vectors there. I just didn't bother making that conditional.

trampoline vectors?

Quoted 1 line

I'll post an updated series soon, with hopes of getting it into 2.6.25

Add the ability to build a ppc_85xx kernel to run at a physical address of 32MB.

Signed-off-by Dale Farnsworth <[email protected]>

---
 arch/powerpc/Kconfig                 |    2 +-
 arch/powerpc/kernel/head_fsl_booke.S |   23 ++++++++++++++++++-----
 arch/powerpc/mm/fsl_booke_mmu.c      |    6 +++---
 3 files changed, 22 insertions(+), 9 deletions(-)

This is needed for the ppc32 /dev/oldmem driver of crash dump.

Signed-off-by Dale Farnsworth <[email protected]>

---
 include/asm-powerpc/highmem.h |   18 ++++++++++++++++++
 1 files changed, 18 insertions(+), 0 deletions(-)

include/asm-powerpc/highmem.h +18 -0

index f7b21ee..88d9e05 100644
@@ -117,6 +117,24 @@ static inline void kunmap_atomic(void *kvaddr, enum km_type type)
 	pagefault_enable();
 }
 
+/* This is the same as kmap_atomic() but can map memory that doesn't
+ * have a struct page associated with it.
+ */
+static inline void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
+{
+	unsigned int idx;
+	unsigned long vaddr;
+
+	pagefault_disable();
+
+	idx = type + KM_TYPE_NR * smp_processor_id();
+	vaddr = KMAP_FIX_BEGIN + idx * PAGE_SIZE;
+	set_pte_at(&init_mm, vaddr, kmap_pte+idx, pfn_pte(pfn, kmap_prot));
+	flush_tlb_page(NULL, vaddr);
+
+	return (void*) vaddr;
+}
+
 static inline struct page *kmap_atomic_to_page(void *ptr)
 {
 	unsigned long idx, vaddr = (unsigned long) ptr;

Quoted 1 line · Dale Farnsworth

This is needed for the ppc32 /dev/oldmem driver of crash dump.

Kumar's working (well, last I heard he was) on a fixmap mechanism so we can do that sort of thing without CONFIG_HIGHMEM, you may want to sync with him here, that would allow to shrink the crash kernel by not having highmem selected.

Cheers,
Ben.

Quoted 34 lines

Signed-off-by Dale Farnsworth <[email protected]>

---
 include/asm-powerpc/highmem.h |   18 ++++++++++++++++++
 1 files changed, 18 insertions(+), 0 deletions(-)

include/asm-powerpc/highmem.h +18 -0

index f7b21ee..88d9e05 100644
@@ -117,6 +117,24 @@ static inline void kunmap_atomic(void *kvaddr, enum km_type type)
 	pagefault_enable();
 }
 
+/* This is the same as kmap_atomic() but can map memory that doesn't
+ * have a struct page associated with it.
+ */
+static inline void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
+{
+	unsigned int idx;
+	unsigned long vaddr;
+
+	pagefault_disable();
+
+	idx = type + KM_TYPE_NR * smp_processor_id();
+	vaddr = KMAP_FIX_BEGIN + idx * PAGE_SIZE;
+	set_pte_at(&init_mm, vaddr, kmap_pte+idx, pfn_pte(pfn, kmap_prot));
+	flush_tlb_page(NULL, vaddr);
+
+	return (void*) vaddr;
+}
+
 static inline struct page *kmap_atomic_to_page(void *ptr)
 {
 	unsigned long idx, vaddr = (unsigned long) ptr;

Quoted 9 lines · Benjamin Herrenschmidt

Quoted 1 line · Dale Farnsworth

This is needed for the ppc32 /dev/oldmem driver of crash dump.

Kumar's working (well, last I heard he was) on a fixmap mechanism so we can do that sort of thing without CONFIG_HIGHMEM, you may want to sync with him here, that would allow to shrink the crash kernel by not having highmem selected.

Quoted 2 lines

Cheers,
Ben.

Kumar, are you close to posting something that would make the patch below unnecessary (or change it significantly)? If so, I'll hold off.

This patch series adds kexec and kdump support for ppc32 in arch/powerpc. It has been successfully tested on the mpc8548_cds and prpmc2800 platforms. Mark Greer and I are preparing patches to the kexec-tools package as well.

Quoted 6 lines · Dale Farnsworth

This patch series adds kexec and kdump support for ppc32 in arch/ powerpc.
It has been successfully tested on the mpc8548_cds and prpmc2800 platforms.
Mark Greer and I are preparing patches to the kexec-tools package as well.

Dale, can you look at updating your patchset now that we've made some progress on other patches.

Quoted 8 lines · Kumar Gala

Quoted 6 lines · Dale Farnsworth

This patch series adds kexec and kdump support for ppc32 in arch/ powerpc.
It has been successfully tested on the mpc8548_cds and prpmc2800 platforms.
Mark Greer and I are preparing patches to the kexec-tools package as well.

Quoted 2 lines

Dale, can you look at updating your patchset now that we've made some progress on other patches.

Yes. It'll take a couple of weeks for me to fit it in though.