On Wed, 2016-08-24 at 15:03 +0530, Aneesh Kumar K.V wrote: > Power9 DD1 requires to update the hid0 register when switching from > hash to radix.
One minor nit. This is bidirectional not just "hash to radix" Could just be: powerpc/mm: Update the HID bit when switching MMU modes Power9 DD1 requires an update to the HID0 register when switching MMU modes ie. radix <-> hash. Otherwise... > Signed-off-by: Aneesh Kumar K.V <[email protected]> Acked-by: Michael Neuling <[email protected]> > --- > arch/powerpc/include/asm/reg.h | 3 +++ > arch/powerpc/mm/hash_utils_64.c | 25 +++++++++++++++++++++++++ > arch/powerpc/mm/pgtable-radix.c | 28 ++++++++++++++++++++++++++++ > 3 files changed, 56 insertions(+) > > diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h > index f69f40f1519a..9dddabc2fced 100644 > --- a/arch/powerpc/include/asm/reg.h > +++ b/arch/powerpc/include/asm/reg.h > @@ -475,6 +475,9 @@ > #define HID0_POWER8_1TO4LPAR __MASK(51) > #define HID0_POWER8_DYNLPARDIS __MASK(48) > > +/* POWER9 HID0 bits */ > +#define HID0_POWER9_RADIX __MASK(63 - 8) > + > #define SPRN_HID1 0x3F1 /* Hardware Implementation Register 1 */ > #ifdef CONFIG_6xx > #define HID1_EMCP (1<<31) /* 7450 Machine Check Pin Enable */ > diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c > index 0821556e16f4..35a6721b3d25 100644 > --- a/arch/powerpc/mm/hash_utils_64.c > +++ b/arch/powerpc/mm/hash_utils_64.c > @@ -711,6 +711,29 @@ int remove_section_mapping(unsigned long start, unsigned > long end) > } > #endif /* CONFIG_MEMORY_HOTPLUG */ > > +static void update_hid_for_hash(void) > +{ > + unsigned long hid0; > + unsigned long rb = 3UL << PPC_BITLSHIFT(53); /* IS = 3 */ > + > + asm volatile("ptesync": : :"memory"); > + /* prs = 0, ric = 2, rs = 0, r = 1 is = 3 */ > + asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1) > + : : "r"(rb), "i"(0), "i"(0), "i"(2), "r"(0) : "memory"); > + asm volatile("eieio; tlbsync; ptesync; isync; slbia": : :"memory"); > + /* > + * now switch the HID > + */ > + hid0 = mfspr(SPRN_HID0); > + hid0 &= ~HID0_POWER9_RADIX; > + mtspr(SPRN_HID0, hid0); > + asm volatile("isync": : :"memory"); > + > + /* Wait for it to happen */ > + while ((mfspr(SPRN_HID0) & HID0_POWER9_RADIX)) > + cpu_relax(); > +} > + > static void __init hash_init_partition_table(phys_addr_t hash_table, > unsigned long htab_size) > { > @@ -737,6 +760,8 @@ static void __init hash_init_partition_table(phys_addr_t > hash_table, > */ > partition_tb->patb1 = 0; > pr_info("Partition table %p\n", partition_tb); > + if (cpu_has_feature(CPU_FTR_POWER9_DD1)) > + update_hid_for_hash(); > /* > * update partition table control register, > * 64 K size. > diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c > index af897d91d09f..8f086352e421 100644 > --- a/arch/powerpc/mm/pgtable-radix.c > +++ b/arch/powerpc/mm/pgtable-radix.c > @@ -294,6 +294,32 @@ found: > return; > } > > +static void update_hid_for_radix(void) > +{ > + unsigned long hid0; > + unsigned long rb = 3UL << PPC_BITLSHIFT(53); /* IS = 3 */ > + > + asm volatile("ptesync": : :"memory"); > + /* prs = 0, ric = 2, rs = 0, r = 1 is = 3 */ > + asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1) > + : : "r"(rb), "i"(1), "i"(0), "i"(2), "r"(0) : "memory"); > + /* prs = 1, ric = 2, rs = 0, r = 1 is = 3 */ > + asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1) > + : : "r"(rb), "i"(1), "i"(1), "i"(2), "r"(0) : "memory"); > + asm volatile("eieio; tlbsync; ptesync; isync; slbia": : :"memory"); > + /* > + * now switch the HID > + */ > + hid0 = mfspr(SPRN_HID0); > + hid0 |= HID0_POWER9_RADIX; > + mtspr(SPRN_HID0, hid0); > + asm volatile("isync": : :"memory"); > + > + /* Wait for it to happen */ > + while (!(mfspr(SPRN_HID0) & HID0_POWER9_RADIX)) > + cpu_relax(); > +} > + > void __init radix__early_init_mmu(void) > { > unsigned long lpcr; > @@ -345,6 +371,8 @@ void __init radix__early_init_mmu(void) > > if (!firmware_has_feature(FW_FEATURE_LPAR)) { > radix_init_native(); > + if (cpu_has_feature(CPU_FTR_POWER9_DD1)) > + update_hid_for_radix(); > lpcr = mfspr(SPRN_LPCR); > mtspr(SPRN_LPCR, lpcr | LPCR_UPRT | LPCR_HR); > radix_init_partition_table();
