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author | Sergei Shtylyov <sshtylyov@ru.mvista.com> | 2006-05-26 19:44:54 +0400 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 2006-06-06 00:15:13 +0100 |
commit | 9370b35175ca43fad7d24bc7b391473f3becbee8 (patch) | |
tree | 4d1f3e7a0708c86da26720288711f8702b00b601 /arch/mips/mm | |
parent | cac4bcbce0e800f2219a27b66aaeb4a33f2e3dbc (diff) | |
download | kernel_samsung_smdk4412-9370b35175ca43fad7d24bc7b391473f3becbee8.zip kernel_samsung_smdk4412-9370b35175ca43fad7d24bc7b391473f3becbee8.tar.gz kernel_samsung_smdk4412-9370b35175ca43fad7d24bc7b391473f3becbee8.tar.bz2 |
[MIPS] Save write-only Config.OD from being clobbered
Save the Config.OD bit from being clobbered by coherency_setup(). This
bit, when set, fixes various errata in the early steppings of Au1x00
SOCs. Unfortunately, the bit was write-only on the most early of them.
In addition, also restore the bit after a wakeup from sleep.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/mm')
-rw-r--r-- | arch/mips/mm/c-r4k.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c index 6b35417..4a43924 100644 --- a/arch/mips/mm/c-r4k.c +++ b/arch/mips/mm/c-r4k.c @@ -1161,6 +1161,31 @@ static void __init setup_scache(void) c->options |= MIPS_CPU_SUBSET_CACHES; } +void au1x00_fixup_config_od(void) +{ + /* + * c0_config.od (bit 19) was write only (and read as 0) + * on the early revisions of Alchemy SOCs. It disables the bus + * transaction overlapping and needs to be set to fix various errata. + */ + switch (read_c0_prid()) { + case 0x00030100: /* Au1000 DA */ + case 0x00030201: /* Au1000 HA */ + case 0x00030202: /* Au1000 HB */ + case 0x01030200: /* Au1500 AB */ + /* + * Au1100 errata actually keeps silence about this bit, so we set it + * just in case for those revisions that require it to be set according + * to arch/mips/au1000/common/cputable.c + */ + case 0x02030200: /* Au1100 AB */ + case 0x02030201: /* Au1100 BA */ + case 0x02030202: /* Au1100 BC */ + set_c0_config(1 << 19); + break; + } +} + static inline void coherency_setup(void) { change_c0_config(CONF_CM_CMASK, CONF_CM_DEFAULT); @@ -1181,6 +1206,15 @@ static inline void coherency_setup(void) case CPU_R4400MC: clear_c0_config(CONF_CU); break; + /* + * We need to catch the ealry Alchemy SOCs with + * the write-only co_config.od bit and set it back to one... + */ + case CPU_AU1000: /* rev. DA, HA, HB */ + case CPU_AU1100: /* rev. AB, BA, BC ?? */ + case CPU_AU1500: /* rev. AB */ + au1x00_fixup_config_od(); + break; } } |