On 07/03/2013 07:52 PM, Sethi Varun-B16395 wrote:

quoted

-----Original Message-----
From: Linuxppc-dev [mailto:linuxppc-dev-
bounces+varun.sethi=freescale.com@lists.ozlabs.org] On Behalf Of Tiejun
Chen
Sent: Thursday, June 20, 2013 1:23 PM
To: benh@kernel.crashing.org
Cc: linuxppc-dev@lists.ozlabs.org; linux-kernel@vger.kernel.org
Subject: [v2][PATCH 1/7] powerpc/book3e: support CONFIG_RELOCATABLE

book3e is different with book3s since 3s includes the exception vectors
code in head_64.S as it relies on absolute addressing which is only
possible within this compilation unit. So we have to get that label
address with got.

And when boot a relocated kernel, we should reset ipvr properly again
after .relocate.

Signed-off-by: Tiejun Chen <redacted>
---
  arch/powerpc/include/asm/exception-64e.h |    8 ++++++++
  arch/powerpc/kernel/exceptions-64e.S     |   15 ++++++++++++++-
  arch/powerpc/kernel/head_64.S            |   22 ++++++++++++++++++++++
  arch/powerpc/lib/feature-fixups.c        |    7 +++++++
  4 files changed, 51 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/exception-64e.h

b/arch/powerpc/include/asm/exception-64e.h
index 51fa43e..89e940d 100644

--- a/arch/powerpc/include/asm/exception-64e.h
+++ b/arch/powerpc/include/asm/exception-64e.h

@@ -214,10 +214,18 @@ exc_##label##_book3e:
  #define TLB_MISS_STATS_SAVE_INFO_BOLTED  #endif

+#ifndef CONFIG_RELOCATABLE
  #define SET_IVOR(vector_number, vector_offset)	\
  	li	r3,vector_offset@l; 		\
  	ori	r3,r3,interrupt_base_book3e@l;	\
  	mtspr	SPRN_IVOR##vector_number,r3;
+#else
+#define SET_IVOR(vector_number, vector_offset)	\
+	LOAD_REG_ADDR(r3,interrupt_base_book3e);\
+	rlwinm	r3,r3,0,15,0;			\
+	ori	r3,r3,vector_offset@l;		\
+	mtspr	SPRN_IVOR##vector_number,r3;
+#endif

[Sethi Varun-B16395] Please add a documentation note here.

Okay.

quoted

  #endif /* _ASM_POWERPC_EXCEPTION_64E_H */

diff --git a/arch/powerpc/kernel/exceptions-64e.S

b/arch/powerpc/kernel/exceptions-64e.S
index 645170a..4b23119 100644

--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S

@@ -1097,7 +1097,15 @@ skpinv:	addi	r6,r6,1

	/* Increment */
   * r4 = MAS0 w/TLBSEL & ESEL for the temp mapping
   */
  	/* Now we branch the new virtual address mapped by this entry */
+#ifdef CONFIG_RELOCATABLE
+	/* We have to find out address from lr. */
+	bl	1f		/* Find our address */
+1:	mflr	r6
+	addi	r6,r6,(2f - 1b)
+	tovirt(r6,r6)
+#else
  	LOAD_REG_IMMEDIATE(r6,2f)
+#endif
  	lis	r7,MSR_KERNEL@h
  	ori	r7,r7,MSR_KERNEL@l
  	mtspr	SPRN_SRR0,r6

@@ -1348,9 +1356,14 @@ _GLOBAL(book3e_secondary_thread_init)
  	mflr	r28
  	b	3b

-_STATIC(init_core_book3e)
+_GLOBAL(init_core_book3e)
  	/* Establish the interrupt vector base */
+#ifdef CONFIG_RELOCATABLE
+	tovirt(r2,r2)
+	LOAD_REG_ADDR(r3, interrupt_base_book3e) #else
  	LOAD_REG_IMMEDIATE(r3, interrupt_base_book3e)
+#endif
  	mtspr	SPRN_IVPR,r3
  	sync
  	blr

[Sethi Varun-B16395] Please add a documentation note here as well.

Okay.

quoted

diff --git a/arch/powerpc/kernel/head_64.S

b/arch/powerpc/kernel/head_64.S index b61363d..0942f3a 100644

--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S

@@ -414,12 +414,22 @@ _STATIC(__after_prom_start)
  	/* process relocations for the final address of the kernel */
  	lis	r25,PAGE_OFFSET@highest	/* compute virtual base of kernel */
  	sldi	r25,r25,32
+#if defined(CONFIG_PPC_BOOK3E)
+	tovirt(r26,r26)			/* on booke, we already run at

PAGE_OFFSET */
+#endif
  	lwz	r7,__run_at_load-_stext(r26)
+#if defined(CONFIG_PPC_BOOK3E)
+	tophys(r26,r26)			/* Restore for the remains. */
+#endif
  	cmplwi	cr0,r7,1	/* flagged to stay where we are ? */
  	bne	1f
  	add	r25,r25,r26
  1:	mr	r3,r25
  	bl	.relocate
+#if defined(CONFIG_PPC_BOOK3E)
+	/* We should set ivpr again after .relocate. */
+	bl	.init_core_book3e
+#endif
  #endif

[Sethi Varun-B16395] A more detailed note over here would be useful.

Okay.

quoted

  /*

@@ -447,12 +457,24 @@ _STATIC(__after_prom_start)
   * variable __run_at_load, if it is set the kernel is treated as

relocatable
   * kernel, otherwise it will be moved to PHYSICAL_START
   */
+#if defined(CONFIG_PPC_BOOK3E)
+	tovirt(r26,r26)			/* on booke, we already run at
PAGE_OFFSET */
+#endif
  	lwz	r7,__run_at_load-_stext(r26)
+#if defined(CONFIG_PPC_BOOK3E)
+	tophys(r26,r26)			/* Restore for the remains. */
+#endif
  	cmplwi	cr0,r7,1
  	bne	3f

+#ifdef CONFIG_PPC_BOOK3E
+	LOAD_REG_ADDR(r5, interrupt_end_book3e)
+	LOAD_REG_ADDR(r11, _stext)
+	sub	r5,r5,r11
+#else
  	/* just copy interrupts */
  	LOAD_REG_IMMEDIATE(r5, __end_interrupts - _stext)
+#endif
  	b	5f
  3:
  #endif

diff --git a/arch/powerpc/lib/feature-fixups.c

b/arch/powerpc/lib/feature-fixups.c
index 7a8a748..13f20ed 100644

--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c

@@ -135,13 +135,20 @@ void do_final_fixups(void)  #if

defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
  	int *src, *dest;
  	unsigned long length;
+#ifdef CONFIG_PPC_BOOK3E
+	extern char interrupt_end_book3e[];
+#endif

[Sethi Varun-B16395] You can simply move this to sections.h and remove the ifdefs.

I would replace interrupt_end_book3e with __end_interrupts then we can have a 
unique label for book3e and book3s as Bharat mentioned previously.

Thanks

Tiejun