[PATCH V2 17/68] powerpc/mm/hash: Add support for POWER9 hash
Aneesh Kumar K.V
aneesh.kumar at linux.vnet.ibm.com
Sun Apr 17 05:06:56 AEST 2016
Balbir Singh <bsingharora at gmail.com> writes:
> On 09/04/16 16:13, Aneesh Kumar K.V wrote:
>> PowerISA 3.0 adds a parition table indexed by LPID. Parition table allow
>> us to specify the MMU model that will be used for guest and host
>> translation.
>>
>> This patch add support with SLB based hash model (UPRT = 0). What is
>> required with this model is to support the new hash page table entry
>> format and also setup Partition table such we use hash table for
>> address translation.
>>
>> We don't have segment table support yet.
>>
>> Inorder to make sure we don't load KVM module on Power9 (since we
>> don't have kvm support yet) this patch also disable kvm on Power9
>>
>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
>> ---
>> arch/powerpc/include/asm/book3s/64/mmu-hash.h | 13 +++++++--
>> arch/powerpc/kvm/book3s_hv.c | 6 ++++
>> arch/powerpc/kvm/book3s_pr.c | 6 +++-
>> arch/powerpc/mm/hash_native_64.c | 11 ++++++-
>> arch/powerpc/mm/hash_utils_64.c | 42 +++++++++++++++++++++++++--
>> arch/powerpc/mm/pgtable_64.c | 7 +++++
>> arch/powerpc/platforms/ps3/htab.c | 2 +-
>> arch/powerpc/platforms/pseries/lpar.c | 2 +-
>> 8 files changed, 81 insertions(+), 8 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
>> index ce73736b42db..843b5d839904 100644
>> --- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
>> +++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
>> @@ -78,6 +78,10 @@
>> #define HPTE_V_SECONDARY ASM_CONST(0x0000000000000002)
>> #define HPTE_V_VALID ASM_CONST(0x0000000000000001)
>>
>> +/*
>> + * ISA 3.0 have a different HPTE format.
>> + */
>> +#define HPTE_R_3_0_SSIZE_SHIFT 58
>> #define HPTE_R_PP0 ASM_CONST(0x8000000000000000)
>> #define HPTE_R_TS ASM_CONST(0x4000000000000000)
>> #define HPTE_R_KEY_HI ASM_CONST(0x3000000000000000)
>> @@ -224,7 +228,8 @@ static inline unsigned long hpte_encode_avpn(unsigned long vpn, int psize,
>> */
>> v = (vpn >> (23 - VPN_SHIFT)) & ~(mmu_psize_defs[psize].avpnm);
>> v <<= HPTE_V_AVPN_SHIFT;
>> - v |= ((unsigned long) ssize) << HPTE_V_SSIZE_SHIFT;
>> + if (!cpu_has_feature(CPU_FTR_ARCH_300))
>> + v |= ((unsigned long) ssize) << HPTE_V_SSIZE_SHIFT;
>> return v;
>> }
>>
>> @@ -248,8 +253,12 @@ static inline unsigned long hpte_encode_v(unsigned long vpn, int base_psize,
>> * aligned for the requested page size
>> */
>> static inline unsigned long hpte_encode_r(unsigned long pa, int base_psize,
>> - int actual_psize)
>> + int actual_psize, int ssize)
>> {
>> +
>> + if (cpu_has_feature(CPU_FTR_ARCH_300))
>> + pa |= ((unsigned long) ssize) << HPTE_R_3_0_SSIZE_SHIFT;
>> +
>
> Looks good, I was wondering if we can compute cpu_has_feature(CPU_FTR_ARCH_300) once for the instance
> and use it, but I am just nit-picking. I've never tried using ASM_MMU_FTR_IF(), I don't know
> if you've explored it. Not very important for this patchset though
There were multiple efforts w.r.t. to this. I tried to fix only
radix_enabled() using code patching. But we also had Kevin doing
http://mid.gmane.org/1440072876-8321-1-git-send-email-haokexin@gmail.com
>
>> /* A 4K page needs no special encoding */
>> if (actual_psize == MMU_PAGE_4K)
>> return pa & HPTE_R_RPN;
>> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
>> index baeddb06811d..c07600efcef6 100644
>> --- a/arch/powerpc/kvm/book3s_hv.c
>> +++ b/arch/powerpc/kvm/book3s_hv.c
>> @@ -3083,6 +3083,12 @@ static int kvmppc_core_check_processor_compat_hv(void)
>> if (!cpu_has_feature(CPU_FTR_HVMODE) ||
>> !cpu_has_feature(CPU_FTR_ARCH_206))
>> return -EIO;
>> + /*
>> + * Disable KVM for Power9, untill the required bits merged.
>> + */
>> + if (cpu_has_feature(CPU_FTR_ARCH_300))
>> + return -EIO;
>> +
>> return 0;
>> }
>>
>> diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
>> index 95bceca8f40e..ffbaf40b7f31 100644
>> --- a/arch/powerpc/kvm/book3s_pr.c
>> +++ b/arch/powerpc/kvm/book3s_pr.c
>> @@ -1683,7 +1683,11 @@ static void kvmppc_core_destroy_vm_pr(struct kvm *kvm)
>>
>> static int kvmppc_core_check_processor_compat_pr(void)
>> {
>> - /* we are always compatible */
>> + /*
>> + * Disable KVM for Power9 untill the required bits merged.
>> + */
>> + if (cpu_has_feature(CPU_FTR_ARCH_300))
>> + return -EIO;
>> return 0;
>> }
>>
>> diff --git a/arch/powerpc/mm/hash_native_64.c b/arch/powerpc/mm/hash_native_64.c
>> index 8eaac81347fd..d873f6507f72 100644
>> --- a/arch/powerpc/mm/hash_native_64.c
>> +++ b/arch/powerpc/mm/hash_native_64.c
>> @@ -221,7 +221,7 @@ static long native_hpte_insert(unsigned long hpte_group, unsigned long vpn,
>> return -1;
>>
>> hpte_v = hpte_encode_v(vpn, psize, apsize, ssize) | vflags | HPTE_V_VALID;
>> - hpte_r = hpte_encode_r(pa, psize, apsize) | rflags;
>> + hpte_r = hpte_encode_r(pa, psize, apsize, ssize) | rflags;
>>
>> if (!(vflags & HPTE_V_BOLTED)) {
>> DBG_LOW(" i=%x hpte_v=%016lx, hpte_r=%016lx\n",
>> @@ -719,6 +719,12 @@ static void native_flush_hash_range(unsigned long number, int local)
>> local_irq_restore(flags);
>> }
>>
>> +static int native_update_partition_table(u64 patb1)
>> +{
>> + partition_tb->patb1 = cpu_to_be64(patb1);
>
> Do we need to tell the hardware that patb1 was updated?
>
you mean do we need sync instructions around ? I checked ISA and don't
find anthing specific.
>> + return 0;
>> +}
>> +
>> void __init hpte_init_native(void)
>> {
>> ppc_md.hpte_invalidate = native_hpte_invalidate;
>> @@ -729,4 +735,7 @@ void __init hpte_init_native(void)
>> ppc_md.hpte_clear_all = native_hpte_clear;
>> ppc_md.flush_hash_range = native_flush_hash_range;
>> ppc_md.hugepage_invalidate = native_hugepage_invalidate;
>> +
>> + if (cpu_has_feature(CPU_FTR_ARCH_300))
>> + ppc_md.update_partition_table = native_update_partition_table;
>> }
>> diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
>> index e924690a5a0e..43e0d86b7ca1 100644
>> --- a/arch/powerpc/mm/hash_utils_64.c
>> +++ b/arch/powerpc/mm/hash_utils_64.c
>> @@ -674,6 +674,41 @@ int remove_section_mapping(unsigned long start, unsigned long end)
>> }
>> #endif /* CONFIG_MEMORY_HOTPLUG */
>>
>> +static void __init hash_init_partition_table(phys_addr_t hash_table,
>> + unsigned long pteg_count)
>> +{
>> + unsigned long ps_field;
>> + unsigned long htab_size;
>> + unsigned long patb_size = 1UL << PATB_SIZE_SHIFT;
>> +
>> + /*
>> + * slb llp encoding for the page size used in VPM real mode.
>> + * We can ignore that for lpid 0
>> + */
>> + ps_field = 0;
>> + htab_size = __ilog2(pteg_count) - 11;
>> +
>> + BUILD_BUG_ON_MSG((PATB_SIZE_SHIFT > 24), "Partition table size too large.");
>> + partition_tb = __va(memblock_alloc_base(patb_size, patb_size,
>> + MEMBLOCK_ALLOC_ANYWHERE));
>> +
>> + /* Initialize the Partition Table with no entries */
>> + memset((void *)partition_tb, 0, patb_size);
>> + partition_tb->patb0 = cpu_to_be64(ps_field | hash_table | htab_size);
>> + /*
>> + * FIXME!! This should be done via update_partition table
>> + * For now UPRT is 0 for us.
>> + */
>> + partition_tb->patb1 = 0;
>
> So the design is that we allocate upto 2^24/16 entries for the partition table
> and set the first entry LPID0 to use HPT with ps_field set to 0 and patb1
> to be updated by the callback we provide via native_update_partition_table?
For hash with SLB we will always find patb1 to be 0. Once we get
segment table, we will have a if(MMU_FTR_SEG_TABLE) here to do this
correctly.
>
>> + DBG("Partition table %p\n", partition_tb);
>> + /*
>> + * update partition table control register,
>> + * 64 K size.
>> + */
>> + mtspr(SPRN_PTCR, __pa(partition_tb) | (PATB_SIZE_SHIFT - 12));
>> +
>> +}
>> +
>> static void __init htab_initialize(void)
>> {
>> unsigned long table;
>> @@ -742,8 +777,11 @@ static void __init htab_initialize(void)
>> /* Initialize the HPT with no entries */
>> memset((void *)table, 0, htab_size_bytes);
>>
>> - /* Set SDR1 */
>> - mtspr(SPRN_SDR1, _SDR1);
>> + if (!cpu_has_feature(CPU_FTR_ARCH_300))
>> + /* Set SDR1 */
>> + mtspr(SPRN_SDR1, _SDR1);
>> + else
>> + hash_init_partition_table(table, pteg_count);
>> }
>>
>> prot = pgprot_val(PAGE_KERNEL);
>> diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
>> index 98c91ad18ba7..5fff787da17a 100644
>> --- a/arch/powerpc/mm/pgtable_64.c
>> +++ b/arch/powerpc/mm/pgtable_64.c
>> @@ -69,6 +69,13 @@
>> #endif
>> #endif
>
> <snip>
>
> Otherwise looks good!
>
> Balbir Singh
Thanks
-aneesh
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