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powerpc: Disable doorbells on Power8 DD1.x

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These processors do not currently support doorbell IPIs, so remove them
from the feature list if we are at DD 1.xx for the 0x004d part.

This fixes a regression caused by d4e58e5928 (powerpc/powernv: Enable
POWER8 doorbell IPIs). With that patch the kernel would hang at boot
when calling smp_call_function_many, as the doorbell would not be
received by the target CPUs:

  .smp_call_function_many+0x2bc/0x3c0 (unreliable)
  .on_each_cpu_mask+0x30/0x100
  .cpuidle_register_driver+0x158/0x1a0
  .cpuidle_register+0x2c/0x110
  .powernv_processor_idle_init+0x23c/0x2c0
  .do_one_initcall+0xd4/0x260
  .kernel_init_freeable+0x25c/0x33c
  .kernel_init+0x1c/0x120
  .ret_from_kernel_thread+0x58/0x7c

Fixes: d4e58e5928 (powerpc/powernv: Enable POWER8 doorbell IPIs)
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Joel Stanley 2014-07-18 11:41:37 +09:30 committed by Benjamin Herrenschmidt
parent f56029410a
commit bd6ba3518f
2 changed files with 21 additions and 0 deletions
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1
arch/powerpc/include/asm/cputable.h
View File

@ -447,6 +447,7 @@ extern const char *powerpc_base_platform;
CPU_FTR_DBELL | CPU_FTR_HAS_PPR | CPU_FTR_DAWR | \
CPU_FTR_ARCH_207S | CPU_FTR_TM_COMP)
#define CPU_FTRS_POWER8E (CPU_FTRS_POWER8 | CPU_FTR_PMAO_BUG)
#define CPU_FTRS_POWER8_DD1 (CPU_FTRS_POWER8 & ~CPU_FTR_DBELL)
#define CPU_FTRS_CELL (CPU_FTR_USE_TB | CPU_FTR_LWSYNC | \
CPU_FTR_PPCAS_ARCH_V2 | CPU_FTR_CTRL | \
CPU_FTR_ALTIVEC_COMP | CPU_FTR_MMCRA | CPU_FTR_SMT | \

20
arch/powerpc/kernel/cputable.c
View File

@ -527,6 +527,26 @@ static struct cpu_spec __initdata cpu_specs[] = {
.machine_check_early = __machine_check_early_realmode_p8,
.platform = "power8",
},
{ /* Power8 DD1: Does not support doorbell IPIs */
.pvr_mask = 0xffffff00,
.pvr_value = 0x004d0100,
.cpu_name = "POWER8 (raw)",
.cpu_features = CPU_FTRS_POWER8_DD1,
.cpu_user_features = COMMON_USER_POWER8,
.cpu_user_features2 = COMMON_USER2_POWER8,
.mmu_features = MMU_FTRS_POWER8,
.icache_bsize = 128,
.dcache_bsize = 128,
.num_pmcs = 6,
.pmc_type = PPC_PMC_IBM,
.oprofile_cpu_type = "ppc64/power8",
.oprofile_type = PPC_OPROFILE_INVALID,
.cpu_setup = __setup_cpu_power8,
.cpu_restore = __restore_cpu_power8,
.flush_tlb = __flush_tlb_power8,
.machine_check_early = __machine_check_early_realmode_p8,
.platform = "power8",
},
{ /* Power8 */
.pvr_mask = 0xffff0000,
.pvr_value = 0x004d0000,