Erratum A004510 says that under certain load conditions, modified cache lines can be discarded, causing data corruption.
To work around this, several CCSR and DCSR register updates need to be made in a careful manner, so that there is no other transaction in corenet when the update is made.
The update is made from a locked cacheline, with a delay before to flush any previous activity, and a delay after to flush the CCSR/DCSR update. We can't use a readback because that would be another corenet transaction, which is not allowed.
We lock the subsequent cacheline to prevent it from being fetched while we're executing the previous cacheline. It is filled with nops so that a branch doesn't cause us to fetch another cacheline.
Ordinarily we are running in a cache-inhibited mapping at this point, so we temporarily change that. We make it guarded so that we should never see a speculative load, and we never do an explicit load. Thus, only the I-cache should ever fill from this mapping, and we flush/unlock it afterward. Thus we should avoid problems from any potential cache aliasing between inhibited and non-inhibited mappings.
NOTE that if PAMU is used with this patch, it will need to use a dedicated LAW as described in the erratum. This is the responsibility of the OS that sets up PAMU.
Signed-off-by: Scott Wood scottwood@freescale.com --- README | 25 +++ arch/powerpc/cpu/mpc85xx/cmd_errata.c | 3 + arch/powerpc/cpu/mpc85xx/release.S | 27 +++ arch/powerpc/cpu/mpc85xx/start.S | 284 +++++++++++++++++++++++++++++ arch/powerpc/include/asm/config_mpc85xx.h | 17 ++ arch/powerpc/include/asm/processor.h | 2 + 6 files changed, 358 insertions(+)
diff --git a/README b/README index fb9d904..abfb019 100644 --- a/README +++ b/README @@ -383,6 +383,31 @@ The following options need to be configured: symbol should be set to the TLB1 entry to be used for this purpose.
+ CONFIG_SYS_FSL_ERRATUM_A004510 + + Enables a workaround for erratum A004510. If set, + then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and + CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. + + CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV + CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) + + Defines one or two SoC revisions (low 8 bits of SVR) + for which the A004510 workaround should be applied. + + The rest of SVR is either not relevant to the decision + of whether the erratum is present (e.g. p2040 versus + p2041) or is implied by the build target, which controls + whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. + + See Freescale App Note 4493 for more information about + this erratum. + + CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY + + This is the value to write into CCSR offset 0x18600 + according to the A004510 workaround. + - Generic CPU options: CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
diff --git a/arch/powerpc/cpu/mpc85xx/cmd_errata.c b/arch/powerpc/cpu/mpc85xx/cmd_errata.c index 4e1a54a..b88b43d 100644 --- a/arch/powerpc/cpu/mpc85xx/cmd_errata.c +++ b/arch/powerpc/cpu/mpc85xx/cmd_errata.c @@ -120,6 +120,9 @@ static int do_errata(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) if ((SVR_MAJ(svr) == 1) || IS_SVR_REV(svr, 2, 0)) puts("Work-around for Erratum NMG ETSEC129 enabled\n"); #endif +#ifdef CONFIG_SYS_FSL_ERRATUM_A004510 + puts("Work-around for Erratum A004510 enabled\n"); +#endif return 0; }
diff --git a/arch/powerpc/cpu/mpc85xx/release.S b/arch/powerpc/cpu/mpc85xx/release.S index 1860684..b19beeb 100644 --- a/arch/powerpc/cpu/mpc85xx/release.S +++ b/arch/powerpc/cpu/mpc85xx/release.S @@ -74,6 +74,33 @@ __secondary_start_page: mtspr 977,r3 #endif
+#ifdef CONFIG_SYS_FSL_ERRATUM_A004510 + mfspr r3,SPRN_SVR + rlwinm r3,r3,0,0xff + li r4,CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV + cmpw r3,r4 + beq 1f + +#ifdef CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 + li r4,CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 + cmpw r3,r4 + beq 1f +#endif + + /* Not a supported revision affected by erratum */ + b 2f + +1: /* Erratum says set bits 55:60 to 001001 */ + msync + isync + mfspr r3,976 + li r4,0x48 + rlwimi r3,r4,0,0x1f8 + mtspr 976,r3 + isync +2: +#endif + /* Enable branch prediction */ lis r3,BUCSR_ENABLE@h ori r3,r3,BUCSR_ENABLE@l diff --git a/arch/powerpc/cpu/mpc85xx/start.S b/arch/powerpc/cpu/mpc85xx/start.S index 742eade..43d20fe 100644 --- a/arch/powerpc/cpu/mpc85xx/start.S +++ b/arch/powerpc/cpu/mpc85xx/start.S @@ -86,6 +86,35 @@ _start_e500: li r1,MSR_DE mtmsr r1
+#ifdef CONFIG_SYS_FSL_ERRATUM_A004510 + mfspr r3,SPRN_SVR + rlwinm r3,r3,0,0xff + li r4,CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV + cmpw r3,r4 + beq 1f + +#ifdef CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 + li r4,CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 + cmpw r3,r4 + beq 1f +#endif + + /* Not a supported revision affected by erratum */ + li r27,0 + b 2f + +1: li r27,1 /* Remember for later that we have the erratum */ + /* Erratum says set bits 55:60 to 001001 */ + msync + isync + mfspr r3,976 + li r4,0x48 + rlwimi r3,r4,0,0x1f8 + mtspr 976,r3 + isync +2: +#endif + #if defined(CONFIG_SECURE_BOOT) && defined(CONFIG_E500MC) /* ISBC uses L2 as stack. * Disable L2 cache here so that u-boot can enable it later @@ -443,6 +472,14 @@ nexti: mflr r1 /* R1 = our PC */ mfspr r2, MAS2 andc r2, r2, r3 or r2, r2, r1 +#ifdef CONFIG_SYS_FSL_ERRATUM_A004510 + cmpwi r27,0 + beq 1f + andi. r15, r2, MAS2_I|MAS2_G /* save the old I/G for later */ + rlwinm r2, r2, 0, ~MAS2_I + ori r2, r2, MAS2_G +1: +#endif mtspr MAS2, r2 /* Set the EPN to our PC base address */
mfspr r2, MAS3 @@ -729,6 +766,253 @@ delete_temp_tlbs: tlbwe #endif /* #if (CONFIG_SYS_CCSRBAR_DEFAULT != CONFIG_SYS_CCSRBAR_PHYS) */
+#ifdef CONFIG_SYS_FSL_ERRATUM_A004510 +#define DCSR_LAWBARH0 (CONFIG_SYS_CCSRBAR + 0x1000) +#define LAW_SIZE_1M 0x13 +#define DCSRBAR_LAWAR (LAW_EN | (0x1d << 20) | LAW_SIZE_1M) + + cmpwi r27,0 + beq 9f + + /* + * Create a TLB entry for CCSR + * + * We're executing out of TLB1 entry in r14, and that's the only + * TLB entry that exists. To allocate some TLB entries for our + * own use, flip a bit high enough that we won't flip it again + * via incrementing. + */ + + xori r8, r14, 32 + lis r0, MAS0_TLBSEL(1)@h + rlwimi r0, r8, 16, MAS0_ESEL_MSK + lis r1, FSL_BOOKE_MAS1(1, 1, 0, 0, BOOKE_PAGESZ_16M)@h + ori r1, r1, FSL_BOOKE_MAS1(1, 1, 0, 0, BOOKE_PAGESZ_16M)@l + lis r7, CONFIG_SYS_CCSRBAR@h + ori r7, r7, CONFIG_SYS_CCSRBAR@l + ori r2, r7, MAS2_I|MAS2_G + lis r3, FSL_BOOKE_MAS3(CONFIG_SYS_CCSRBAR_PHYS_LOW, 0, (MAS3_SW|MAS3_SR))@h + ori r3, r3, FSL_BOOKE_MAS3(CONFIG_SYS_CCSRBAR_PHYS_LOW, 0, (MAS3_SW|MAS3_SR))@l + lis r4, CONFIG_SYS_CCSRBAR_PHYS_HIGH@h + ori r4, r4, CONFIG_SYS_CCSRBAR_PHYS_HIGH@l + mtspr MAS0, r0 + mtspr MAS1, r1 + mtspr MAS2, r2 + mtspr MAS3, r3 + mtspr MAS7, r4 + isync + tlbwe + isync + msync + + /* Map DCSR temporarily to physical address zero */ + li r0, 0 + lis r3, DCSRBAR_LAWAR@h + ori r3, r3, DCSRBAR_LAWAR@l + + stw r0, 0xc00(r7) /* LAWBARH0 */ + stw r0, 0xc04(r7) /* LAWBARL0 */ + sync + stw r3, 0xc08(r7) /* LAWAR0 */ + + /* Read back from LAWAR to ensure the update is complete. */ + lwz r3, 0xc08(r7) /* LAWAR0 */ + isync + + /* Create a TLB entry for DCSR at zero */ + + addi r9, r8, 1 + lis r0, MAS0_TLBSEL(1)@h + rlwimi r0, r9, 16, MAS0_ESEL_MSK + lis r1, FSL_BOOKE_MAS1(1, 1, 0, 0, BOOKE_PAGESZ_1M)@h + ori r1, r1, FSL_BOOKE_MAS1(1, 1, 0, 0, BOOKE_PAGESZ_1M)@l + li r6, 0 /* DCSR effective address */ + ori r2, r6, MAS2_I|MAS2_G + li r3, MAS3_SW|MAS3_SR + li r4, 0 + mtspr MAS0, r0 + mtspr MAS1, r1 + mtspr MAS2, r2 + mtspr MAS3, r3 + mtspr MAS7, r4 + isync + tlbwe + isync + msync + + /* enable the timebase */ +#define CTBENR 0xe2084 + li r3, 1 + addis r4, r7, CTBENR@ha + stw r3, CTBENR@l(r4) + lwz r3, CTBENR@l(r4) + twi 0,r3,0 + isync + + .macro erratum_set_ccsr offset value + addis r3, r7, \offset@ha + lis r4, \value@h + addi r3, r3, \offset@l + ori r4, r4, \value@l + bl erratum_set_value + .endm + + .macro erratum_set_dcsr offset value + addis r3, r6, \offset@ha + lis r4, \value@h + addi r3, r3, \offset@l + ori r4, r4, \value@l + bl erratum_set_value + .endm + + erratum_set_dcsr 0xb0e08 0xe0201800 + erratum_set_dcsr 0xb0e18 0xe0201800 + erratum_set_dcsr 0xb0e38 0xe0400000 + erratum_set_dcsr 0xb0008 0x00900000 + erratum_set_dcsr 0xb0e40 0xe00a0000 + erratum_set_ccsr 0x18600 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY + erratum_set_ccsr 0x10f00 0x415e5000 + erratum_set_ccsr 0x11f00 0x415e5000 + + /* Make temp mapping uncacheable again, if it was initially */ + bl 2f +2: mflr r3 + tlbsx 0, r3 + mfspr r4, MAS2 + rlwimi r4, r15, 0, MAS2_I + rlwimi r4, r15, 0, MAS2_G + mtspr MAS2, r4 + isync + tlbwe + isync + msync + + /* Clear the cache */ + lis r3,(L1CSR1_ICFI|L1CSR1_ICLFR)@h + ori r3,r3,(L1CSR1_ICFI|L1CSR1_ICLFR)@l + sync + isync + mtspr SPRN_L1CSR1,r3 + isync +2: sync + mfspr r4,SPRN_L1CSR1 + and. r4,r4,r3 + bne 2b + + lis r3,(L1CSR1_CPE|L1CSR1_ICE)@h + ori r3,r3,(L1CSR1_CPE|L1CSR1_ICE)@l + sync + isync + mtspr SPRN_L1CSR1,r3 + isync +2: sync + mfspr r4,SPRN_L1CSR1 + and. r4,r4,r3 + beq 2b + + /* Remove temporary mappings */ + lis r0, MAS0_TLBSEL(1)@h + rlwimi r0, r9, 16, MAS0_ESEL_MSK + li r3, 0 + mtspr MAS0, r0 + mtspr MAS1, r3 + isync + tlbwe + isync + msync + + li r3, 0 + stw r3, 0xc08(r7) /* LAWAR0 */ + lwz r3, 0xc08(r7) + isync + + lis r0, MAS0_TLBSEL(1)@h + rlwimi r0, r8, 16, MAS0_ESEL_MSK + li r3, 0 + mtspr MAS0, r0 + mtspr MAS1, r3 + isync + tlbwe + isync + msync + + b 9f + + /* r3 = addr, r4 = value, clobbers r5, r11, r12 */ +erratum_set_value: + /* Lock two cache lines into I-Cache */ + sync + mfspr r11, SPRN_L1CSR1 + rlwinm r11, r11, 0, ~L1CSR1_ICUL + sync + isync + mtspr SPRN_L1CSR1, r11 + isync + + mflr r12 + bl 5f +5: mflr r5 + addi r5, r5, 2f - 5b + icbtls 0, 0, r5 + addi r5, r5, 64 + + sync + mfspr r11, SPRN_L1CSR1 +3: andi. r11, r11, L1CSR1_ICUL + bne 3b + + icbtls 0, 0, r5 + addi r5, r5, 64 + + sync + mfspr r11, SPRN_L1CSR1 +3: andi. r11, r11, L1CSR1_ICUL + bne 3b + + b 2f + .align 6 + /* Inside a locked cacheline, wait a while, write, then wait a while */ +2: sync + + mfspr r5, SPRN_TBRL + addis r11, r5, 0x10000@h /* wait 65536 timebase ticks */ +4: mfspr r5, SPRN_TBRL + subf. r5, r5, r11 + bgt 4b + + stw r4, 0(r3) + + mfspr r5, SPRN_TBRL + addis r11, r5, 0x10000@h /* wait 65536 timebase ticks */ +4: mfspr r5, SPRN_TBRL + subf. r5, r5, r11 + bgt 4b + + sync + + /* + * Fill out the rest of this cache line and the next with nops, + * to ensure that nothing outside the locked area will be + * fetched due to a branch. + */ + .rept 19 + nop + .endr + + sync + mfspr r11, SPRN_L1CSR1 + rlwinm r11, r11, 0, ~L1CSR1_ICUL + sync + isync + mtspr SPRN_L1CSR1, r11 + isync + + mtlr r12 + blr + +9: +#endif + create_init_ram_area: lis r6,FSL_BOOKE_MAS0(1, 15, 0)@h ori r6,r6,FSL_BOOKE_MAS0(1, 15, 0)@l diff --git a/arch/powerpc/include/asm/config_mpc85xx.h b/arch/powerpc/include/asm/config_mpc85xx.h index 17bba26..fd30f15 100644 --- a/arch/powerpc/include/asm/config_mpc85xx.h +++ b/arch/powerpc/include/asm/config_mpc85xx.h @@ -357,6 +357,10 @@ #define CONFIG_SYS_FSL_SRIO_MAX_PORTS 2 #define CONFIG_SYS_FSL_SRIO_OB_WIN_NUM 9 #define CONFIG_SYS_FSL_SRIO_IB_WIN_NUM 5 +#define CONFIG_SYS_FSL_ERRATUM_A004510 +#define CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 0x10 +#define CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 0x11 +#define CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 0xf0000000
#elif defined(CONFIG_PPC_P3041) #define CONFIG_MAX_CPUS 4 @@ -381,6 +385,10 @@ #define CONFIG_SYS_FSL_SRIO_MAX_PORTS 2 #define CONFIG_SYS_FSL_SRIO_OB_WIN_NUM 9 #define CONFIG_SYS_FSL_SRIO_IB_WIN_NUM 5 +#define CONFIG_SYS_FSL_ERRATUM_A004510 +#define CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 0x10 +#define CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 0x11 +#define CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 0xf0000000
#elif defined(CONFIG_PPC_P3060) #define CONFIG_MAX_CPUS 8 @@ -400,6 +408,9 @@ #define CONFIG_SYS_FSL_SRIO_MAX_PORTS 2 #define CONFIG_SYS_FSL_SRIO_OB_WIN_NUM 9 #define CONFIG_SYS_FSL_SRIO_IB_WIN_NUM 5 +#define CONFIG_SYS_FSL_ERRATUM_A004510 +#define CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 0x10 +#define CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 0xff000000
#elif defined(CONFIG_PPC_P4080) /* also supports P4040 */ #define CONFIG_MAX_CPUS 8 @@ -436,6 +447,9 @@ #define CONFIG_SYS_FSL_SRIO_IB_WIN_NUM 5 #define CONFIG_SYS_FSL_RMU #define CONFIG_SYS_FSL_SRIO_MSG_UNIT_NUM 2 +#define CONFIG_SYS_FSL_ERRATUM_A004510 +#define CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 0x20 +#define CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 0xff000000
#elif defined(CONFIG_PPC_P5020) /* also supports P5010 */ #define CONFIG_MAX_CPUS 2 @@ -459,6 +473,9 @@ #define CONFIG_SYS_FSL_SRIO_MAX_PORTS 2 #define CONFIG_SYS_FSL_SRIO_OB_WIN_NUM 9 #define CONFIG_SYS_FSL_SRIO_IB_WIN_NUM 5 +#define CONFIG_SYS_FSL_ERRATUM_A004510 +#define CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 0x10 +#define CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 0xc0000000
#elif defined(CONFIG_BSC9131) #define CONFIG_MAX_CPUS 1 diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index 0de3685..60a11ea 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -486,11 +486,13 @@ #define SPRN_L2CFG0 0x207 /* L2 Cache Configuration Register 0 */ #define SPRN_L1CSR0 0x3f2 /* L1 Data Cache Control and Status Register 0 */ #define L1CSR0_CPE 0x00010000 /* Data Cache Parity Enable */ +#define L1CSR0_CUL 0x00000400 /* (D-)Cache Unable to Lock */ #define L1CSR0_DCLFR 0x00000100 /* D-Cache Lock Flash Reset */ #define L1CSR0_DCFI 0x00000002 /* Data Cache Flash Invalidate */ #define L1CSR0_DCE 0x00000001 /* Data Cache Enable */ #define SPRN_L1CSR1 0x3f3 /* L1 Instruction Cache Control and Status Register 1 */ #define L1CSR1_CPE 0x00010000 /* Instruction Cache Parity Enable */ +#define L1CSR1_ICUL 0x00000400 /* I-Cache Unable to Lock */ #define L1CSR1_ICLFR 0x00000100 /* I-Cache Lock Flash Reset */ #define L1CSR1_ICFI 0x00000002 /* Instruction Cache Flash Invalidate */ #define L1CSR1_ICE 0x00000001 /* Instruction Cache Enable */