From 026a2078791b64aede220b1b1a3e4dfe4ab175e7 Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Wed, 26 Jan 2011 13:41:05 +0100 Subject: [PATCH 1/3] microblaze: Fix DTB passing from bootloader Little endian system needs to check OF_DT_HEADER but it is swapped because it is in big-endian. Microblaze LE provides lwr instruction which loads magic number in BIG endian format which can be compared. There is used the fact that if you write 0x1 as word and load it as byte then you get for big-endian zero and 1 for little-endian. Signed-off-by: Michal Simek --- arch/microblaze/kernel/head.S | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/arch/microblaze/kernel/head.S b/arch/microblaze/kernel/head.S index 42434008209e..0db20b5abb54 100644 --- a/arch/microblaze/kernel/head.S +++ b/arch/microblaze/kernel/head.S @@ -77,8 +77,18 @@ real_start: We ensure r7 points to a valid FDT, just in case the bootloader is broken or non-existent */ beqi r7, no_fdt_arg /* NULL pointer? don't copy */ - lw r11, r0, r7 /* Does r7 point to a */ - rsubi r11, r11, OF_DT_HEADER /* valid FDT? */ +/* Does r7 point to a valid FDT? Load HEADER magic number */ + /* Run time Big/Little endian platform */ + /* Save 1 as word and load byte - 0 - BIG, 1 - LITTLE */ + addik r11, r0, 0x1 /* BIG/LITTLE checking value */ + /* __bss_start will be zeroed later - it is just temp location */ + swi r11, r0, TOPHYS(__bss_start) + lbui r11, r0, TOPHYS(__bss_start) + beqid r11, big_endian /* DO NOT break delay stop dependency */ + lw r11, r0, r7 /* Big endian load in delay slot */ + lwr r11, r0, r7 /* Little endian load */ +big_endian: + rsubi r11, r11, OF_DT_HEADER /* Check FDT header */ beqi r11, _prepare_copy_fdt or r7, r0, r0 /* clear R7 when not valid DTB */ bnei r11, no_fdt_arg /* No - get out of here */ From 9c749e177ccc0b3ee9589425c7255079e7a726fc Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Fri, 28 Jan 2011 13:14:58 +0100 Subject: [PATCH 2/3] microblaze: Fix unaligned issue on MMU system with BS=0 DIV=1 Unaligned code use shift for finding register operand. There is used BSRLI(r8,r8,2) macro which is expand for BS=0, DIV=1 by ori rD, r0, (1 << imm); \ idivu rD, rD, rA but if rD is equal rA then ori instruction rewrite value which should be devide. The patch remove this macro which use idivu instruction because idivu takes 32/34 cycles. The highest shifting is 20 which takes 20 cycles. Signed-off-by: Michal Simek --- arch/microblaze/kernel/hw_exception_handler.S | 4 ---- 1 file changed, 4 deletions(-) diff --git a/arch/microblaze/kernel/hw_exception_handler.S b/arch/microblaze/kernel/hw_exception_handler.S index 25f6e07d8de8..782680de3121 100644 --- a/arch/microblaze/kernel/hw_exception_handler.S +++ b/arch/microblaze/kernel/hw_exception_handler.S @@ -147,10 +147,6 @@ #if CONFIG_XILINX_MICROBLAZE0_USE_BARREL > 0 #define BSRLI(rD, rA, imm) \ bsrli rD, rA, imm - #elif CONFIG_XILINX_MICROBLAZE0_USE_DIV > 0 - #define BSRLI(rD, rA, imm) \ - ori rD, r0, (1 << imm); \ - idivu rD, rD, rA #else #define BSRLI(rD, rA, imm) BSRLI ## imm (rD, rA) /* Only the used shift constants defined here - add more if needed */ From de93c3c119382cb888ca8a94b642dbcf8035525e Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Fri, 28 Jan 2011 13:26:54 +0100 Subject: [PATCH 3/3] microblaze: Fix ASM optimized code for LE Microblaze little-endian doesn't support ASM optimized library functions(memcpy/memmove). Kconfig doens't contain any information about endian that's why it is necessary to check it in the source code. The code is used with barrel shifter is used. Signed-off-by: Michal Simek --- arch/microblaze/lib/fastcopy.S | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/microblaze/lib/fastcopy.S b/arch/microblaze/lib/fastcopy.S index fdc48bb065d8..62021d7e249e 100644 --- a/arch/microblaze/lib/fastcopy.S +++ b/arch/microblaze/lib/fastcopy.S @@ -29,6 +29,10 @@ * between mem locations with size of xfer spec'd in bytes */ +#ifdef __MICROBLAZEEL__ +#error Microblaze LE not support ASM optimized lib func. Disable OPT_LIB_ASM. +#endif + #include .text .globl memcpy