diff options
Diffstat (limited to 'arch/powerpc/cpu/ppc4xx/cpu_init.c')
| -rw-r--r-- | arch/powerpc/cpu/ppc4xx/cpu_init.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/powerpc/cpu/ppc4xx/cpu_init.c b/arch/powerpc/cpu/ppc4xx/cpu_init.c index bf208adfe6..970a8c1e2d 100644 --- a/arch/powerpc/cpu/ppc4xx/cpu_init.c +++ b/arch/powerpc/cpu/ppc4xx/cpu_init.c @@ -221,6 +221,66 @@ void reconfigure_pll(u32 new_cpu_freq) #endif } +#ifdef CONFIG_SYS_4xx_CHIP_21_ERRATA +void +chip_21_errata(void) +{ + /* + * See rev 1.09 of the 405EX/405EXr errata. CHIP_21 says that + * sometimes reading the PVR and/or SDR0_ECID results in incorrect + * values. Since the rev-D chip uses the SDR0_ECID bits to control + * internal features, that means the second PCIe or ethernet of an EX + * variant could fail to work. Also, security features of both EX and + * EXr might be incorrectly disabled. + * + * The suggested workaround is as follows (covering rev-C and rev-D): + * + * 1.Read the PVR and SDR0_ECID3. + * + * 2.If the PVR matches an expected Revision C PVR value AND if + * SDR0_ECID3[12:15] is different from PVR[28:31], then processor is + * Revision C: continue executing the initialization code (no reset + * required). else go to step 3. + * + * 3.If the PVR matches an expected Revision D PVR value AND if + * SDR0_ECID3[10:11] matches its expected value, then continue + * executing initialization code, no reset required. else write + * DBCR0[RST] = 0b11 to generate a SysReset. + */ + + u32 pvr; + u32 pvr_28_31; + u32 ecid3; + u32 ecid3_10_11; + u32 ecid3_12_15; + + /* Step 1: */ + pvr = get_pvr(); + mfsdr(SDR0_ECID3, ecid3); + + /* Step 2: */ + pvr_28_31 = pvr & 0xf; + ecid3_10_11 = (ecid3 >> 20) & 0x3; + ecid3_12_15 = (ecid3 >> 16) & 0xf; + if ((pvr == CONFIG_405EX_CHIP21_PVR_REV_C) && + (pvr_28_31 != ecid3_12_15)) { + /* No reset required. */ + return; + } + + /* Step 3: */ + if ((pvr == CONFIG_405EX_CHIP21_PVR_REV_D) && + (ecid3_10_11 == CONFIG_405EX_CHIP21_ECID3_REV_D)) { + /* No reset required. */ + return; + } + + /* Reset required. */ + __asm__ __volatile__ ("sync; isync"); + mtspr(SPRN_DBCR0, 0x30000000); +} +#endif + /* * Breath some life into the CPU... * @@ -235,6 +295,10 @@ cpu_init_f (void) u32 val; #endif +#ifdef CONFIG_SYS_4xx_CHIP_21_ERRATA + chip_21_errata(); +#endif + reconfigure_pll(CONFIG_SYS_PLL_RECONFIG); #if (defined(CONFIG_405EP) || defined (CONFIG_405EX)) && \ |