[SPARC64]: Initial sun4v TLB miss handling infrastructure.
Things are a little tricky because, unlike sun4u, we have
to:
1) do a hypervisor trap to do the TLB load.
2) do the TSB lookup calculations by hand
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc64/kernel/head.S b/arch/sparc64/kernel/head.S
index 7840271..03fc0b5 100644
--- a/arch/sparc64/kernel/head.S
+++ b/arch/sparc64/kernel/head.S
@@ -474,6 +474,7 @@
sparc64_boot_end:
#include "systbls.S"
+#include "sun4v_tlb_miss.S"
#include "ktlb.S"
#include "tsb.S"
#include "etrap.S"
diff --git a/arch/sparc64/kernel/ktlb.S b/arch/sparc64/kernel/ktlb.S
index c133543..2e55084 100644
--- a/arch/sparc64/kernel/ktlb.S
+++ b/arch/sparc64/kernel/ktlb.S
@@ -16,12 +16,16 @@
.text
.align 32
- .globl kvmap_itlb
kvmap_itlb:
/* g6: TAG TARGET */
mov TLB_TAG_ACCESS, %g4
ldxa [%g4] ASI_IMMU, %g4
+ /* sun4v_itlb_miss branches here with the missing virtual
+ * address already loaded into %g4
+ */
+kvmap_itlb_4v:
+
kvmap_itlb_nonlinear:
/* Catch kernel NULL pointer calls. */
sethi %hi(PAGE_SIZE), %g5
@@ -94,11 +98,15 @@
nop
.align 32
- .globl kvmap_dtlb
kvmap_dtlb:
/* %g6: TAG TARGET */
mov TLB_TAG_ACCESS, %g4
ldxa [%g4] ASI_DMMU, %g4
+
+ /* sun4v_dtlb_miss branches here with the missing virtual
+ * address already loaded into %g4
+ */
+kvmap_dtlb_4v:
brgez,pn %g4, kvmap_dtlb_nonlinear
nop
diff --git a/arch/sparc64/kernel/sun4v_tlb_miss.S b/arch/sparc64/kernel/sun4v_tlb_miss.S
new file mode 100644
index 0000000..58ea5dd
--- /dev/null
+++ b/arch/sparc64/kernel/sun4v_tlb_miss.S
@@ -0,0 +1,219 @@
+/* sun4v_tlb_miss.S: Sun4v TLB miss handlers.
+ *
+ * Copyright (C) 2006 <davem@davemloft.net>
+ */
+
+ .text
+ .align 32
+
+sun4v_itlb_miss:
+ /* Load CPU ID into %g3. */
+ mov SCRATCHPAD_CPUID, %g1
+ ldxa [%g1] ASI_SCRATCHPAD, %g3
+
+ /* Load UTSB reg into %g1. */
+ ldxa [%g1 + %g1] ASI_SCRATCHPAD, %g1
+
+ /* Load &trap_block[smp_processor_id()] into %g2. */
+ sethi %hi(trap_block), %g2
+ or %g2, %lo(trap_block), %g2
+ sllx %g3, TRAP_BLOCK_SZ_SHIFT, %g3
+ add %g2, %g3, %g2
+
+ /* Create a TAG TARGET, "(vaddr>>22) | (ctx << 48)", in %g6.
+ * Branch if kernel TLB miss. The kernel TSB and user TSB miss
+ * code wants the missing virtual address in %g4, so that value
+ * cannot be modified through the entirety of this handler.
+ */
+ ldx [%g2 + TRAP_PER_CPU_FAULT_INFO + HV_FAULT_I_ADDR_OFFSET], %g4
+ ldx [%g2 + TRAP_PER_CPU_FAULT_INFO + HV_FAULT_I_CTX_OFFSET], %g5
+ srlx %g4, 22, %g3
+ sllx %g5, 48, %g6
+ or %g6, %g3, %g6
+ brz,pn %g5, kvmap_itlb_4v
+ nop
+
+ /* Create TSB pointer. This is something like:
+ *
+ * index_mask = (512 << (tsb_reg & 0x7UL)) - 1UL;
+ * tsb_base = tsb_reg & ~0x7UL;
+ */
+ and %g1, 0x7, %g3
+ andn %g1, 0x7, %g1
+ mov 512, %g7
+ sllx %g7, %g3, %g7
+ sub %g7, 1, %g7
+
+ /* TSB index mask is in %g7, tsb base is in %g1. Compute
+ * the TSB entry pointer into %g1:
+ *
+ * tsb_index = ((vaddr >> PAGE_SHIFT) & tsb_mask);
+ * tsb_ptr = tsb_base + (tsb_index * 16);
+ */
+ srlx %g4, PAGE_SHIFT, %g3
+ and %g3, %g7, %g3
+ sllx %g3, 4, %g3
+ add %g1, %g3, %g1
+
+ /* Load TSB tag/pte into %g2/%g3 and compare the tag. */
+ ldda [%g1] ASI_QUAD_LDD_PHYS, %g2
+ cmp %g2, %g6
+ sethi %hi(_PAGE_EXEC), %g7
+ bne,a,pn %xcc, tsb_miss_page_table_walk
+ mov FAULT_CODE_ITLB, %g3
+ andcc %g3, %g7, %g0
+ be,a,pn %xcc, tsb_do_fault
+ mov FAULT_CODE_ITLB, %g3
+
+ /* We have a valid entry, make hypervisor call to load
+ * I-TLB and return from trap.
+ *
+ * %g3: PTE
+ * %g4: vaddr
+ * %g6: TAG TARGET (only "CTX << 48" part matters)
+ */
+sun4v_itlb_load:
+ mov %o0, %g1 ! save %o0
+ mov %o1, %g2 ! save %o1
+ mov %o2, %g5 ! save %o2
+ mov %o3, %g7 ! save %o3
+ mov %g4, %o0 ! vaddr
+ srlx %g6, 48, %o1 ! ctx
+ mov %g3, %o2 ! PTE
+ mov HV_MMU_IMMU, %o3 ! flags
+ ta HV_MMU_MAP_ADDR_TRAP
+ mov %g1, %o0 ! restore %o0
+ mov %g2, %o1 ! restore %o1
+ mov %g5, %o2 ! restore %o2
+ mov %g7, %o3 ! restore %o3
+
+ retry
+
+sun4v_dtlb_miss:
+ /* Load CPU ID into %g3. */
+ mov SCRATCHPAD_CPUID, %g1
+ ldxa [%g1] ASI_SCRATCHPAD, %g3
+
+ /* Load UTSB reg into %g1. */
+ ldxa [%g1 + %g1] ASI_SCRATCHPAD, %g1
+
+ /* Load &trap_block[smp_processor_id()] into %g2. */
+ sethi %hi(trap_block), %g2
+ or %g2, %lo(trap_block), %g2
+ sllx %g3, TRAP_BLOCK_SZ_SHIFT, %g3
+ add %g2, %g3, %g2
+
+ /* Create a TAG TARGET, "(vaddr>>22) | (ctx << 48)", in %g6.
+ * Branch if kernel TLB miss. The kernel TSB and user TSB miss
+ * code wants the missing virtual address in %g4, so that value
+ * cannot be modified through the entirety of this handler.
+ */
+ ldx [%g2 + TRAP_PER_CPU_FAULT_INFO + HV_FAULT_D_ADDR_OFFSET], %g4
+ ldx [%g2 + TRAP_PER_CPU_FAULT_INFO + HV_FAULT_D_CTX_OFFSET], %g5
+ srlx %g4, 22, %g3
+ sllx %g5, 48, %g6
+ or %g6, %g3, %g6
+ brz,pn %g5, kvmap_dtlb_4v
+ nop
+
+ /* Create TSB pointer. This is something like:
+ *
+ * index_mask = (512 << (tsb_reg & 0x7UL)) - 1UL;
+ * tsb_base = tsb_reg & ~0x7UL;
+ */
+ and %g1, 0x7, %g3
+ andn %g1, 0x7, %g1
+ mov 512, %g7
+ sllx %g7, %g3, %g7
+ sub %g7, 1, %g7
+
+ /* TSB index mask is in %g7, tsb base is in %g1. Compute
+ * the TSB entry pointer into %g1:
+ *
+ * tsb_index = ((vaddr >> PAGE_SHIFT) & tsb_mask);
+ * tsb_ptr = tsb_base + (tsb_index * 16);
+ */
+ srlx %g4, PAGE_SHIFT, %g3
+ and %g3, %g7, %g3
+ sllx %g3, 4, %g3
+ add %g1, %g3, %g1
+
+ /* Load TSB tag/pte into %g2/%g3 and compare the tag. */
+ ldda [%g1] ASI_QUAD_LDD_PHYS, %g2
+ cmp %g2, %g6
+ bne,a,pn %xcc, tsb_miss_page_table_walk
+ mov FAULT_CODE_ITLB, %g3
+
+ /* We have a valid entry, make hypervisor call to load
+ * D-TLB and return from trap.
+ *
+ * %g3: PTE
+ * %g4: vaddr
+ * %g6: TAG TARGET (only "CTX << 48" part matters)
+ */
+sun4v_dtlb_load:
+ mov %o0, %g1 ! save %o0
+ mov %o1, %g2 ! save %o1
+ mov %o2, %g5 ! save %o2
+ mov %o3, %g7 ! save %o3
+ mov %g4, %o0 ! vaddr
+ srlx %g6, 48, %o1 ! ctx
+ mov %g3, %o2 ! PTE
+ mov HV_MMU_DMMU, %o3 ! flags
+ ta HV_MMU_MAP_ADDR_TRAP
+ mov %g1, %o0 ! restore %o0
+ mov %g2, %o1 ! restore %o1
+ mov %g5, %o2 ! restore %o2
+ mov %g7, %o3 ! restore %o3
+
+ retry
+
+sun4v_dtlb_prot:
+ /* Load CPU ID into %g3. */
+ mov SCRATCHPAD_CPUID, %g1
+ ldxa [%g1] ASI_SCRATCHPAD, %g3
+
+ /* Load &trap_block[smp_processor_id()] into %g2. */
+ sethi %hi(trap_block), %g2
+ or %g2, %lo(trap_block), %g2
+ sllx %g3, TRAP_BLOCK_SZ_SHIFT, %g3
+ add %g2, %g3, %g2
+
+ ldx [%g2 + TRAP_PER_CPU_FAULT_INFO + HV_FAULT_D_ADDR_OFFSET], %g5
+ rdpr %tl, %g1
+ cmp %g1, 1
+ bgu,pn %xcc, winfix_trampoline
+ nop
+ ba,pt %xcc, sparc64_realfault_common
+ mov FAULT_CODE_DTLB | FAULT_CODE_WRITE, %g4
+
+#define BRANCH_ALWAYS 0x10680000
+#define NOP 0x01000000
+#define SUN4V_DO_PATCH(OLD, NEW) \
+ sethi %hi(NEW), %g1; \
+ or %g1, %lo(NEW), %g1; \
+ sethi %hi(OLD), %g2; \
+ or %g2, %lo(OLD), %g2; \
+ sub %g1, %g2, %g1; \
+ sethi %hi(BRANCH_ALWAYS), %g3; \
+ srl %g1, 2, %g1; \
+ or %g3, %lo(BRANCH_ALWAYS), %g3; \
+ or %g3, %g1, %g3; \
+ stw %g3, [%g2]; \
+ sethi %hi(NOP), %g3; \
+ or %g3, %lo(NOP), %g3; \
+ stw %g3, [%g2 + 0x4]; \
+ flush %g2;
+
+ .globl sun4v_patch_tlb_handlers
+ .type sun4v_patch_tlb_handlers,#function
+sun4v_patch_tlb_handlers:
+ SUN4V_DO_PATCH(tl0_iamiss, sun4v_itlb_miss)
+ SUN4V_DO_PATCH(tl1_iamiss, sun4v_itlb_miss)
+ SUN4V_DO_PATCH(tl0_damiss, sun4v_dtlb_miss)
+ SUN4V_DO_PATCH(tl1_damiss, sun4v_dtlb_miss)
+ SUN4V_DO_PATCH(tl0_daprot, sun4v_dtlb_prot)
+ SUN4V_DO_PATCH(tl1_daprot, sun4v_dtlb_prot)
+ retl
+ nop
+ .size sun4v_patch_tlb_handlers,.-sun4v_patch_tlb_handlers
diff --git a/arch/sparc64/kernel/tsb.S b/arch/sparc64/kernel/tsb.S
index 96e6316..818bc9e 100644
--- a/arch/sparc64/kernel/tsb.S
+++ b/arch/sparc64/kernel/tsb.S
@@ -18,30 +18,33 @@
* %g4: available temporary
* %g5: available temporary
* %g6: TAG TARGET
- * %g7: physical address base of the linux page
+ * %g7: available temporary, will be loaded by us with
+ * the physical address base of the linux page
* tables for the current address space
*/
- .globl tsb_miss_dtlb
tsb_miss_dtlb:
mov TLB_TAG_ACCESS, %g4
ldxa [%g4] ASI_DMMU, %g4
ba,pt %xcc, tsb_miss_page_table_walk
nop
- .globl tsb_miss_itlb
tsb_miss_itlb:
mov TLB_TAG_ACCESS, %g4
ldxa [%g4] ASI_IMMU, %g4
ba,pt %xcc, tsb_miss_page_table_walk
nop
+ /* The sun4v TLB miss handlers jump directly here instead
+ * of tsb_miss_{d,i}tlb with the missing virtual address
+ * already loaded into %g4.
+ */
tsb_miss_page_table_walk:
TRAP_LOAD_PGD_PHYS(%g7, %g5)
USER_PGTABLE_WALK_TL1(%g4, %g7, %g5, %g2, tsb_do_fault)
tsb_reload:
- TSB_LOCK_TAG(%g1, %g2, %g4)
+ TSB_LOCK_TAG(%g1, %g2, %g7)
/* Load and check PTE. */
ldxa [%g5] ASI_PHYS_USE_EC, %g5
@@ -52,9 +55,9 @@
* bother putting it into the TSB.
*/
srlx %g5, 32, %g2
- sethi %hi(_PAGE_ALL_SZ_BITS >> 32), %g4
+ sethi %hi(_PAGE_ALL_SZ_BITS >> 32), %g7
+ and %g2, %g7, %g2
sethi %hi(_PAGE_SZBITS >> 32), %g7
- and %g2, %g4, %g2
cmp %g2, %g7
bne,a,pn %xcc, tsb_tlb_reload
TSB_STORE(%g1, %g0)
@@ -68,12 +71,54 @@
nop
tsb_dtlb_load:
- stxa %g5, [%g0] ASI_DTLB_DATA_IN
+
+661: stxa %g5, [%g0] ASI_DTLB_DATA_IN
retry
+ .section .gl_2insn_patch, "ax"
+ .word 661b
+ nop
+ nop
+ .previous
+
+ /* For sun4v the ASI_DTLB_DATA_IN store and the retry
+ * instruction get nop'd out and we get here to branch
+ * to the sun4v tlb load code. The registers are setup
+ * as follows:
+ *
+ * %g4: vaddr
+ * %g5: PTE
+ * %g6: TAG
+ *
+ * The sun4v TLB load wants the PTE in %g3 so we fix that
+ * up here.
+ */
+ ba,pt %xcc, sun4v_dtlb_load
+ mov %g5, %g3
tsb_itlb_load:
- stxa %g5, [%g0] ASI_ITLB_DATA_IN
+
+661: stxa %g5, [%g0] ASI_ITLB_DATA_IN
retry
+ .section .gl_2insn_patch, "ax"
+ .word 661b
+ nop
+ nop
+ .previous
+
+ /* For sun4v the ASI_ITLB_DATA_IN store and the retry
+ * instruction get nop'd out and we get here to branch
+ * to the sun4v tlb load code. The registers are setup
+ * as follows:
+ *
+ * %g4: vaddr
+ * %g5: PTE
+ * %g6: TAG
+ *
+ * The sun4v TLB load wants the PTE in %g3 so we fix that
+ * up here.
+ */
+ ba,pt %xcc, sun4v_itlb_load
+ mov %g5, %g3
/* No valid entry in the page tables, do full fault
* processing.
@@ -95,10 +140,17 @@
nop
tsb_do_dtlb_fault:
- rdpr %tl, %g4
- cmp %g4, 1
- mov TLB_TAG_ACCESS, %g4
+ rdpr %tl, %g3
+ cmp %g3, 1
+
+661: mov TLB_TAG_ACCESS, %g4
ldxa [%g4] ASI_DMMU, %g5
+ .section .gl_2insn_patch, "ax"
+ .word 661b
+ mov %g4, %g5
+ nop
+ .previous
+
be,pt %xcc, sparc64_realfault_common
mov FAULT_CODE_DTLB, %g4
ba,pt %xcc, winfix_trampoline
@@ -196,12 +248,23 @@
add %g2, %g1, %g2
stx %o0, [%g2 + TRAP_PER_CPU_PGD_PADDR]
- mov TSB_REG, %g1
+661: mov TSB_REG, %g1
stxa %o1, [%g1] ASI_DMMU
+ .section .gl_2insn_patch, "ax"
+ .word 661b
+ mov SCRATCHPAD_UTSBREG1, %g1
+ stxa %o1, [%g1] ASI_SCRATCHPAD
+ .previous
+
membar #Sync
- stxa %o1, [%g1] ASI_IMMU
+661: stxa %o1, [%g1] ASI_IMMU
membar #Sync
+ .section .gl_2insn_patch, "ax"
+ .word 661b
+ nop
+ nop
+ .previous
brz %o2, 9f
nop
diff --git a/arch/sparc64/kernel/vmlinux.lds.S b/arch/sparc64/kernel/vmlinux.lds.S
index 686bf6b..a09a8a23 100644
--- a/arch/sparc64/kernel/vmlinux.lds.S
+++ b/arch/sparc64/kernel/vmlinux.lds.S
@@ -71,6 +71,9 @@
__con_initcall_end = .;
SECURITY_INIT
. = ALIGN(4);
+ __tsb_ldquad_phys_patch = .;
+ .tsb_ldquad_phys_patch : { *(.tsb_ldquad_phys_patch) }
+ __tsb_ldquad_phys_patch_end = .;
__tsb_phys_patch = .;
.tsb_phys_patch : { *(.tsb_phys_patch) }
__tsb_phys_patch_end = .;
diff --git a/arch/sparc64/mm/init.c b/arch/sparc64/mm/init.c
index ab50cd9..e9aac42 100644
--- a/arch/sparc64/mm/init.c
+++ b/arch/sparc64/mm/init.c
@@ -1050,8 +1050,25 @@
static void __init tsb_phys_patch(void)
{
+ struct tsb_ldquad_phys_patch_entry *pquad;
struct tsb_phys_patch_entry *p;
+ pquad = &__tsb_ldquad_phys_patch;
+ while (pquad < &__tsb_ldquad_phys_patch_end) {
+ unsigned long addr = pquad->addr;
+
+ if (tlb_type == hypervisor)
+ *(unsigned int *) addr = pquad->sun4v_insn;
+ else
+ *(unsigned int *) addr = pquad->sun4u_insn;
+ wmb();
+ __asm__ __volatile__("flush %0"
+ : /* no outputs */
+ : "r" (addr));
+
+ pquad++;
+ }
+
p = &__tsb_phys_patch;
while (p < &__tsb_phys_patch_end) {
unsigned long addr = p->addr;
@@ -1069,6 +1086,7 @@
/* paging_init() sets up the page tables */
extern void cheetah_ecache_flush_init(void);
+extern void sun4v_patch_tlb_handlers(void);
static unsigned long last_valid_pfn;
pgd_t swapper_pg_dir[2048];
@@ -1078,9 +1096,13 @@
unsigned long end_pfn, pages_avail, shift;
unsigned long real_end, i;
- if (tlb_type == cheetah_plus)
+ if (tlb_type == cheetah_plus ||
+ tlb_type == hypervisor)
tsb_phys_patch();
+ if (tlb_type == hypervisor)
+ sun4v_patch_tlb_handlers();
+
/* Find available physical memory... */
read_obp_memory("available", &pavail[0], &pavail_ents);