From d257d5da39a78b32721ca84b2ba7f461f2f7ed7f Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 6 Feb 2006 23:44:37 -0800 Subject: [PATCH] [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 --- arch/sparc64/kernel/head.S | 1 + arch/sparc64/kernel/ktlb.S | 12 +- arch/sparc64/kernel/sun4v_tlb_miss.S | 219 +++++++++++++++++++++++++++ arch/sparc64/kernel/tsb.S | 89 +++++++++-- arch/sparc64/kernel/vmlinux.lds.S | 3 + arch/sparc64/mm/init.c | 24 ++- include/asm-sparc64/cpudata.h | 8 +- include/asm-sparc64/tsb.h | 11 +- 8 files changed, 349 insertions(+), 18 deletions(-) create mode 100644 arch/sparc64/kernel/sun4v_tlb_miss.S diff --git a/arch/sparc64/kernel/head.S b/arch/sparc64/kernel/head.S index 7840271d7a..03fc0b5b1d 100644 --- a/arch/sparc64/kernel/head.S +++ b/arch/sparc64/kernel/head.S @@ -474,6 +474,7 @@ setup_tba: 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 c133543212..2e55084a0c 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 @@ kvmap_dtlb_obp: 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 0000000000..58ea5dd857 --- /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 + */ + + .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 96e63168d8..818bc9e913 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 @@ tsb_reload: * 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 @@ tsb_tlb_reload: 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 @@ tsb_do_fault: 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 @@ __tsb_context_switch: 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 686bf6b3b0..a09a8a2383 100644 --- a/arch/sparc64/kernel/vmlinux.lds.S +++ b/arch/sparc64/kernel/vmlinux.lds.S @@ -71,6 +71,9 @@ SECTIONS __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 ab50cd9618..e9aac42487 100644 --- a/arch/sparc64/mm/init.c +++ b/arch/sparc64/mm/init.c @@ -1050,8 +1050,25 @@ unsigned long __init find_ecache_flush_span(unsigned long size) 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 @@ static void __init tsb_phys_patch(void) /* 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 @@ void __init paging_init(void) 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); diff --git a/include/asm-sparc64/cpudata.h b/include/asm-sparc64/cpudata.h index 998145b926..a3dc4afc4b 100644 --- a/include/asm-sparc64/cpudata.h +++ b/include/asm-sparc64/cpudata.h @@ -6,6 +6,8 @@ #ifndef _SPARC64_CPUDATA_H #define _SPARC64_CPUDATA_H +#include + #ifndef __ASSEMBLY__ #include @@ -57,6 +59,9 @@ struct trap_per_cpu { /* D-cache line 2 */ unsigned long __pad2[4]; + +/* Dcache lines 3 and 4 */ + struct hv_fault_status fault_info; } __attribute__((aligned(64))); extern struct trap_per_cpu trap_block[NR_CPUS]; extern void init_cur_cpu_trap(void); @@ -88,8 +93,9 @@ extern struct gl_2insn_patch_entry __gl_2insn_patch, __gl_2insn_patch_end; #define TRAP_PER_CPU_THREAD 0x00 #define TRAP_PER_CPU_PGD_PADDR 0x08 +#define TRAP_PER_CPU_FAULT_INFO 0x20 -#define TRAP_BLOCK_SZ_SHIFT 6 +#define TRAP_BLOCK_SZ_SHIFT 7 #include diff --git a/include/asm-sparc64/tsb.h b/include/asm-sparc64/tsb.h index 44709cde56..7f3abc32c4 100644 --- a/include/asm-sparc64/tsb.h +++ b/include/asm-sparc64/tsb.h @@ -53,6 +53,14 @@ * kernel image, so we don't play these games for swapper_tsb access. */ #ifndef __ASSEMBLY__ +struct tsb_ldquad_phys_patch_entry { + unsigned int addr; + unsigned int sun4u_insn; + unsigned int sun4v_insn; +}; +extern struct tsb_ldquad_phys_patch_entry __tsb_ldquad_phys_patch, + __tsb_ldquad_phys_patch_end; + struct tsb_phys_patch_entry { unsigned int addr; unsigned int insn; @@ -61,9 +69,10 @@ extern struct tsb_phys_patch_entry __tsb_phys_patch, __tsb_phys_patch_end; #endif #define TSB_LOAD_QUAD(TSB, REG) \ 661: ldda [TSB] ASI_NUCLEUS_QUAD_LDD, REG; \ - .section .tsb_phys_patch, "ax"; \ + .section .tsb_ldquad_phys_patch, "ax"; \ .word 661b; \ ldda [TSB] ASI_QUAD_LDD_PHYS, REG; \ + ldda [TSB] ASI_QUAD_LDD_PHYS_4V, REG; \ .previous #define TSB_LOAD_TAG_HIGH(TSB, REG) \ -- 2.39.5