From 90f30a710a3c619b5405860a686c4ddfc495d4b6 Mon Sep 17 00:00:00 2001 From: Dave Liu Date: Thu, 2 Nov 2006 18:05:50 -0600 Subject: [PATCH] mpc83xx: Fix the incorrect dcbz operation The 834x rev1.x silicon has one CPU5 errata. The issue is when the data cache locked with HID0[DLOCK], the dcbz instruction looks like no-op inst. The right behavior of the data cache is when the data cache Locked with HID0[DLOCK], the dcbz instruction allocates new tags in cache. The 834x rev3.0 and later and 8360 have not this bug inside. So, when 834x rev3.0/8360 are working with ECC, the dcbz instruction will corrupt the stack in cache, the processor will checkstop reset. However, the 834x rev1.x can work with ECC with these code, because the sillicon has this cache bug. The dcbz will not corrupt the stack in cache. Really, it is the fault code running on fault sillicon. This patch fix the incorrect dcbz operation. Instead of CPU FP writing to initialise the ECC. CHANGELOG: * Fix the incorrect dcbz operation instead of CPU FP writing to initialise the ECC memory. Otherwise, it will corrupt the stack in cache, The processor will checkstop reset. Signed-off-by: Dave Liu --- board/mpc8360emds/mpc8360emds.c | 4 +++ cpu/mpc83xx/spd_sdram.c | 52 ++++++++++++--------------------- cpu/mpc83xx/start.S | 12 ++++++++ include/common.h | 5 ++++ 4 files changed, 39 insertions(+), 34 deletions(-) diff --git a/board/mpc8360emds/mpc8360emds.c b/board/mpc8360emds/mpc8360emds.c index 5bbaa5cf2e..a9b1d9eb32 100644 --- a/board/mpc8360emds/mpc8360emds.c +++ b/board/mpc8360emds/mpc8360emds.c @@ -535,6 +535,7 @@ int do_ecc(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[]) /* write memory location injecting errors */ ppcDWstore((u32 *) i, pattern); + __asm__ __volatile__("sync"); /* disable injects */ ddr->ecc_err_inject &= ~ECC_ERR_INJECT_EIEN; @@ -543,10 +544,12 @@ int do_ecc(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[]) /* read data, this generates ECC error */ ppcDWload((u32 *) i, ret); + __asm__ __volatile__("sync"); /* re-initialize memory, double word write the location again, * generates new ECC code this time */ ppcDWstore((u32 *) i, writeback); + __asm__ __volatile__("sync"); } enable_interrupts(); return 0; @@ -588,6 +591,7 @@ int do_ecc(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[]) * double word write the location again, * generates new ECC code this time */ ppcDWstore((u32 *) i, writeback); + __asm__ __volatile__("sync"); } enable_interrupts(); return 0; diff --git a/cpu/mpc83xx/spd_sdram.c b/cpu/mpc83xx/spd_sdram.c index acc8c9e79b..b91c6130e7 100644 --- a/cpu/mpc83xx/spd_sdram.c +++ b/cpu/mpc83xx/spd_sdram.c @@ -562,54 +562,38 @@ static __inline__ unsigned long get_tbms (void) /* #define CONFIG_DDR_ECC_INIT_VIA_DMA */ void ddr_enable_ecc(unsigned int dram_size) { - uint *p; volatile immap_t *immap = (immap_t *)CFG_IMMRBAR; volatile ddr83xx_t *ddr= &immap->ddr; unsigned long t_start, t_end; + register u64 *p; + register uint size; + unsigned int pattern[2]; #if defined(CONFIG_DDR_ECC_INIT_VIA_DMA) uint i; #endif - - debug("Initialize a Cachline in DRAM\n"); icache_enable(); - -#if defined(CONFIG_DDR_ECC_INIT_VIA_DMA) - /* Initialise DMA for direct Transfers */ - dma_init(); -#endif - t_start = get_tbms(); + pattern[0] = 0xdeadbeef; + pattern[1] = 0xdeadbeef; #if !defined(CONFIG_DDR_ECC_INIT_VIA_DMA) - debug("DDR init: Cache flush method\n"); - for (p = 0; p < (uint *)(dram_size); p++) { - if (((unsigned int)p & 0x1f) == 0) { - ppcDcbz((unsigned long) p); - } - - /* write pattern to cache and flush */ - *p = (unsigned int)0xdeadbeef; - - if (((unsigned int)p & 0x1c) == 0x1c) { - ppcDcbf((unsigned long) p); - } + debug("ddr init: CPU FP write method\n"); + size = dram_size; + for (p = 0; p < (u64*)(size); p++) { + ppcDWstore((u32*)p, pattern); } + __asm__ __volatile__ ("sync"); #else - printf("DDR init: DMA method\n"); - for (p = 0; p < (uint *)(8 * 1024); p++) { - /* zero one data cache line */ - if (((unsigned int)p & 0x1f) == 0) { - ppcDcbz((unsigned long)p); - } - - /* write pattern to it and flush */ - *p = (unsigned int)0xdeadbeef; - - if (((unsigned int)p & 0x1c) == 0x1c) { - ppcDcbf((unsigned long)p); - } + debug("ddr init: DMA method\n"); + size = 0x2000; + for (p = 0; p < (u64*)(size); p++) { + ppcDWstore((u32*)p, pattern); } + __asm__ __volatile__ ("sync"); + /* Initialise DMA for direct transfer */ + dma_init(); + /* Start DMA to transfer */ dma_xfer((uint *)0x2000, 0x2000, (uint *)0); /* 8K */ dma_xfer((uint *)0x4000, 0x4000, (uint *)0); /* 16K */ dma_xfer((uint *)0x8000, 0x8000, (uint *)0); /* 32K */ diff --git a/cpu/mpc83xx/start.S b/cpu/mpc83xx/start.S index a7ed3c5b2c..c43835c8dc 100644 --- a/cpu/mpc83xx/start.S +++ b/cpu/mpc83xx/start.S @@ -870,6 +870,18 @@ ppcDcbz: dcbz r0,r3 blr + .globl ppcDWstore +ppcDWstore: + lfd 1, 0(r4) + stfd 1, 0(r3) + blr + + .globl ppcDWload +ppcDWload: + lfd 1, 0(r3) + stfd 1, 0(r4) + blr + /*-------------------------------------------------------------------*/ /* diff --git a/include/common.h b/include/common.h index 349d5cf726..0be8372cc5 100644 --- a/include/common.h +++ b/include/common.h @@ -402,6 +402,11 @@ void ppcSync(void); void ppcDcbz(unsigned long value); #endif +#if defined (CONFIG_MPC83XX) +void ppcDWload(unsigned int *addr, unsigned int *ret); +void ppcDWstore(unsigned int *addr, unsigned int *value); +#endif + /* $(CPU)/cpu.c */ int checkcpu (void); int checkicache (void); -- 2.25.1