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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/mips/mm/tlbex.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/mips/mm/tlbex.c')
-rw-r--r--arch/mips/mm/tlbex.c2603
1 files changed, 2603 insertions, 0 deletions
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
new file mode 100644
index 0000000000..b4e1c783e6
--- /dev/null
+++ b/arch/mips/mm/tlbex.c
@@ -0,0 +1,2603 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Synthesize TLB refill handlers at runtime.
+ *
+ * Copyright (C) 2004, 2005, 2006, 2008 Thiemo Seufer
+ * Copyright (C) 2005, 2007, 2008, 2009 Maciej W. Rozycki
+ * Copyright (C) 2006 Ralf Baechle (ralf@linux-mips.org)
+ * Copyright (C) 2008, 2009 Cavium Networks, Inc.
+ * Copyright (C) 2011 MIPS Technologies, Inc.
+ *
+ * ... and the days got worse and worse and now you see
+ * I've gone completely out of my mind.
+ *
+ * They're coming to take me a away haha
+ * they're coming to take me a away hoho hihi haha
+ * to the funny farm where code is beautiful all the time ...
+ *
+ * (Condolences to Napoleon XIV)
+ */
+
+#include <linux/bug.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/smp.h>
+#include <linux/string.h>
+#include <linux/cache.h>
+#include <linux/pgtable.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cpu-type.h>
+#include <asm/mmu_context.h>
+#include <asm/uasm.h>
+#include <asm/setup.h>
+#include <asm/tlbex.h>
+
+static int mips_xpa_disabled;
+
+static int __init xpa_disable(char *s)
+{
+ mips_xpa_disabled = 1;
+
+ return 1;
+}
+
+__setup("noxpa", xpa_disable);
+
+/*
+ * TLB load/store/modify handlers.
+ *
+ * Only the fastpath gets synthesized at runtime, the slowpath for
+ * do_page_fault remains normal asm.
+ */
+extern void tlb_do_page_fault_0(void);
+extern void tlb_do_page_fault_1(void);
+
+struct work_registers {
+ int r1;
+ int r2;
+ int r3;
+};
+
+struct tlb_reg_save {
+ unsigned long a;
+ unsigned long b;
+} ____cacheline_aligned_in_smp;
+
+static struct tlb_reg_save handler_reg_save[NR_CPUS];
+
+static inline int r45k_bvahwbug(void)
+{
+ /* XXX: We should probe for the presence of this bug, but we don't. */
+ return 0;
+}
+
+static inline int r4k_250MHZhwbug(void)
+{
+ /* XXX: We should probe for the presence of this bug, but we don't. */
+ return 0;
+}
+
+extern int sb1250_m3_workaround_needed(void);
+
+static inline int __maybe_unused bcm1250_m3_war(void)
+{
+ if (IS_ENABLED(CONFIG_SB1_PASS_2_WORKAROUNDS))
+ return sb1250_m3_workaround_needed();
+ return 0;
+}
+
+static inline int __maybe_unused r10000_llsc_war(void)
+{
+ return IS_ENABLED(CONFIG_WAR_R10000_LLSC);
+}
+
+static int use_bbit_insns(void)
+{
+ switch (current_cpu_type()) {
+ case CPU_CAVIUM_OCTEON:
+ case CPU_CAVIUM_OCTEON_PLUS:
+ case CPU_CAVIUM_OCTEON2:
+ case CPU_CAVIUM_OCTEON3:
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+static int use_lwx_insns(void)
+{
+ switch (current_cpu_type()) {
+ case CPU_CAVIUM_OCTEON2:
+ case CPU_CAVIUM_OCTEON3:
+ return 1;
+ default:
+ return 0;
+ }
+}
+#if defined(CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE) && \
+ CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE > 0
+static bool scratchpad_available(void)
+{
+ return true;
+}
+static int scratchpad_offset(int i)
+{
+ /*
+ * CVMSEG starts at address -32768 and extends for
+ * CAVIUM_OCTEON_CVMSEG_SIZE 128 byte cache lines.
+ */
+ i += 1; /* Kernel use starts at the top and works down. */
+ return CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE * 128 - (8 * i) - 32768;
+}
+#else
+static bool scratchpad_available(void)
+{
+ return false;
+}
+static int scratchpad_offset(int i)
+{
+ BUG();
+ /* Really unreachable, but evidently some GCC want this. */
+ return 0;
+}
+#endif
+/*
+ * Found by experiment: At least some revisions of the 4kc throw under
+ * some circumstances a machine check exception, triggered by invalid
+ * values in the index register. Delaying the tlbp instruction until
+ * after the next branch, plus adding an additional nop in front of
+ * tlbwi/tlbwr avoids the invalid index register values. Nobody knows
+ * why; it's not an issue caused by the core RTL.
+ *
+ */
+static int m4kc_tlbp_war(void)
+{
+ return current_cpu_type() == CPU_4KC;
+}
+
+/* Handle labels (which must be positive integers). */
+enum label_id {
+ label_second_part = 1,
+ label_leave,
+ label_vmalloc,
+ label_vmalloc_done,
+ label_tlbw_hazard_0,
+ label_split = label_tlbw_hazard_0 + 8,
+ label_tlbl_goaround1,
+ label_tlbl_goaround2,
+ label_nopage_tlbl,
+ label_nopage_tlbs,
+ label_nopage_tlbm,
+ label_smp_pgtable_change,
+ label_r3000_write_probe_fail,
+ label_large_segbits_fault,
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ label_tlb_huge_update,
+#endif
+};
+
+UASM_L_LA(_second_part)
+UASM_L_LA(_leave)
+UASM_L_LA(_vmalloc)
+UASM_L_LA(_vmalloc_done)
+/* _tlbw_hazard_x is handled differently. */
+UASM_L_LA(_split)
+UASM_L_LA(_tlbl_goaround1)
+UASM_L_LA(_tlbl_goaround2)
+UASM_L_LA(_nopage_tlbl)
+UASM_L_LA(_nopage_tlbs)
+UASM_L_LA(_nopage_tlbm)
+UASM_L_LA(_smp_pgtable_change)
+UASM_L_LA(_r3000_write_probe_fail)
+UASM_L_LA(_large_segbits_fault)
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+UASM_L_LA(_tlb_huge_update)
+#endif
+
+static int hazard_instance;
+
+static void uasm_bgezl_hazard(u32 **p, struct uasm_reloc **r, int instance)
+{
+ switch (instance) {
+ case 0 ... 7:
+ uasm_il_bgezl(p, r, 0, label_tlbw_hazard_0 + instance);
+ return;
+ default:
+ BUG();
+ }
+}
+
+static void uasm_bgezl_label(struct uasm_label **l, u32 **p, int instance)
+{
+ switch (instance) {
+ case 0 ... 7:
+ uasm_build_label(l, *p, label_tlbw_hazard_0 + instance);
+ break;
+ default:
+ BUG();
+ }
+}
+
+/*
+ * pgtable bits are assigned dynamically depending on processor feature
+ * and statically based on kernel configuration. This spits out the actual
+ * values the kernel is using. Required to make sense from disassembled
+ * TLB exception handlers.
+ */
+static void output_pgtable_bits_defines(void)
+{
+#define pr_define(fmt, ...) \
+ pr_debug("#define " fmt, ##__VA_ARGS__)
+
+ pr_debug("#include <asm/asm.h>\n");
+ pr_debug("#include <asm/regdef.h>\n");
+ pr_debug("\n");
+
+ pr_define("_PAGE_PRESENT_SHIFT %d\n", _PAGE_PRESENT_SHIFT);
+ pr_define("_PAGE_NO_READ_SHIFT %d\n", _PAGE_NO_READ_SHIFT);
+ pr_define("_PAGE_WRITE_SHIFT %d\n", _PAGE_WRITE_SHIFT);
+ pr_define("_PAGE_ACCESSED_SHIFT %d\n", _PAGE_ACCESSED_SHIFT);
+ pr_define("_PAGE_MODIFIED_SHIFT %d\n", _PAGE_MODIFIED_SHIFT);
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ pr_define("_PAGE_HUGE_SHIFT %d\n", _PAGE_HUGE_SHIFT);
+#endif
+#ifdef _PAGE_NO_EXEC_SHIFT
+ if (cpu_has_rixi)
+ pr_define("_PAGE_NO_EXEC_SHIFT %d\n", _PAGE_NO_EXEC_SHIFT);
+#endif
+ pr_define("_PAGE_GLOBAL_SHIFT %d\n", _PAGE_GLOBAL_SHIFT);
+ pr_define("_PAGE_VALID_SHIFT %d\n", _PAGE_VALID_SHIFT);
+ pr_define("_PAGE_DIRTY_SHIFT %d\n", _PAGE_DIRTY_SHIFT);
+ pr_define("PFN_PTE_SHIFT %d\n", PFN_PTE_SHIFT);
+ pr_debug("\n");
+}
+
+static inline void dump_handler(const char *symbol, const void *start, const void *end)
+{
+ unsigned int count = (end - start) / sizeof(u32);
+ const u32 *handler = start;
+ int i;
+
+ pr_debug("LEAF(%s)\n", symbol);
+
+ pr_debug("\t.set push\n");
+ pr_debug("\t.set noreorder\n");
+
+ for (i = 0; i < count; i++)
+ pr_debug("\t.word\t0x%08x\t\t# %p\n", handler[i], &handler[i]);
+
+ pr_debug("\t.set\tpop\n");
+
+ pr_debug("\tEND(%s)\n", symbol);
+}
+
+/* The only general purpose registers allowed in TLB handlers. */
+#define K0 26
+#define K1 27
+
+/* Some CP0 registers */
+#define C0_INDEX 0, 0
+#define C0_ENTRYLO0 2, 0
+#define C0_TCBIND 2, 2
+#define C0_ENTRYLO1 3, 0
+#define C0_CONTEXT 4, 0
+#define C0_PAGEMASK 5, 0
+#define C0_PWBASE 5, 5
+#define C0_PWFIELD 5, 6
+#define C0_PWSIZE 5, 7
+#define C0_PWCTL 6, 6
+#define C0_BADVADDR 8, 0
+#define C0_PGD 9, 7
+#define C0_ENTRYHI 10, 0
+#define C0_EPC 14, 0
+#define C0_XCONTEXT 20, 0
+
+#ifdef CONFIG_64BIT
+# define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_XCONTEXT)
+#else
+# define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_CONTEXT)
+#endif
+
+/* The worst case length of the handler is around 18 instructions for
+ * R3000-style TLBs and up to 63 instructions for R4000-style TLBs.
+ * Maximum space available is 32 instructions for R3000 and 64
+ * instructions for R4000.
+ *
+ * We deliberately chose a buffer size of 128, so we won't scribble
+ * over anything important on overflow before we panic.
+ */
+static u32 tlb_handler[128];
+
+/* simply assume worst case size for labels and relocs */
+static struct uasm_label labels[128];
+static struct uasm_reloc relocs[128];
+
+static int check_for_high_segbits;
+static bool fill_includes_sw_bits;
+
+static unsigned int kscratch_used_mask;
+
+static inline int __maybe_unused c0_kscratch(void)
+{
+ return 31;
+}
+
+static int allocate_kscratch(void)
+{
+ int r;
+ unsigned int a = cpu_data[0].kscratch_mask & ~kscratch_used_mask;
+
+ r = ffs(a);
+
+ if (r == 0)
+ return -1;
+
+ r--; /* make it zero based */
+
+ kscratch_used_mask |= (1 << r);
+
+ return r;
+}
+
+static int scratch_reg;
+int pgd_reg;
+EXPORT_SYMBOL_GPL(pgd_reg);
+enum vmalloc64_mode {not_refill, refill_scratch, refill_noscratch};
+
+static struct work_registers build_get_work_registers(u32 **p)
+{
+ struct work_registers r;
+
+ if (scratch_reg >= 0) {
+ /* Save in CPU local C0_KScratch? */
+ UASM_i_MTC0(p, 1, c0_kscratch(), scratch_reg);
+ r.r1 = K0;
+ r.r2 = K1;
+ r.r3 = 1;
+ return r;
+ }
+
+ if (num_possible_cpus() > 1) {
+ /* Get smp_processor_id */
+ UASM_i_CPUID_MFC0(p, K0, SMP_CPUID_REG);
+ UASM_i_SRL_SAFE(p, K0, K0, SMP_CPUID_REGSHIFT);
+
+ /* handler_reg_save index in K0 */
+ UASM_i_SLL(p, K0, K0, ilog2(sizeof(struct tlb_reg_save)));
+
+ UASM_i_LA(p, K1, (long)&handler_reg_save);
+ UASM_i_ADDU(p, K0, K0, K1);
+ } else {
+ UASM_i_LA(p, K0, (long)&handler_reg_save);
+ }
+ /* K0 now points to save area, save $1 and $2 */
+ UASM_i_SW(p, 1, offsetof(struct tlb_reg_save, a), K0);
+ UASM_i_SW(p, 2, offsetof(struct tlb_reg_save, b), K0);
+
+ r.r1 = K1;
+ r.r2 = 1;
+ r.r3 = 2;
+ return r;
+}
+
+static void build_restore_work_registers(u32 **p)
+{
+ if (scratch_reg >= 0) {
+ uasm_i_ehb(p);
+ UASM_i_MFC0(p, 1, c0_kscratch(), scratch_reg);
+ return;
+ }
+ /* K0 already points to save area, restore $1 and $2 */
+ UASM_i_LW(p, 1, offsetof(struct tlb_reg_save, a), K0);
+ UASM_i_LW(p, 2, offsetof(struct tlb_reg_save, b), K0);
+}
+
+#ifndef CONFIG_MIPS_PGD_C0_CONTEXT
+
+/*
+ * CONFIG_MIPS_PGD_C0_CONTEXT implies 64 bit and lack of pgd_current,
+ * we cannot do r3000 under these circumstances.
+ *
+ * The R3000 TLB handler is simple.
+ */
+static void build_r3000_tlb_refill_handler(void)
+{
+ long pgdc = (long)pgd_current;
+ u32 *p;
+
+ memset(tlb_handler, 0, sizeof(tlb_handler));
+ p = tlb_handler;
+
+ uasm_i_mfc0(&p, K0, C0_BADVADDR);
+ uasm_i_lui(&p, K1, uasm_rel_hi(pgdc)); /* cp0 delay */
+ uasm_i_lw(&p, K1, uasm_rel_lo(pgdc), K1);
+ uasm_i_srl(&p, K0, K0, 22); /* load delay */
+ uasm_i_sll(&p, K0, K0, 2);
+ uasm_i_addu(&p, K1, K1, K0);
+ uasm_i_mfc0(&p, K0, C0_CONTEXT);
+ uasm_i_lw(&p, K1, 0, K1); /* cp0 delay */
+ uasm_i_andi(&p, K0, K0, 0xffc); /* load delay */
+ uasm_i_addu(&p, K1, K1, K0);
+ uasm_i_lw(&p, K0, 0, K1);
+ uasm_i_nop(&p); /* load delay */
+ uasm_i_mtc0(&p, K0, C0_ENTRYLO0);
+ uasm_i_mfc0(&p, K1, C0_EPC); /* cp0 delay */
+ uasm_i_tlbwr(&p); /* cp0 delay */
+ uasm_i_jr(&p, K1);
+ uasm_i_rfe(&p); /* branch delay */
+
+ if (p > tlb_handler + 32)
+ panic("TLB refill handler space exceeded");
+
+ pr_debug("Wrote TLB refill handler (%u instructions).\n",
+ (unsigned int)(p - tlb_handler));
+
+ memcpy((void *)ebase, tlb_handler, 0x80);
+ local_flush_icache_range(ebase, ebase + 0x80);
+ dump_handler("r3000_tlb_refill", (u32 *)ebase, (u32 *)(ebase + 0x80));
+}
+#endif /* CONFIG_MIPS_PGD_C0_CONTEXT */
+
+/*
+ * The R4000 TLB handler is much more complicated. We have two
+ * consecutive handler areas with 32 instructions space each.
+ * Since they aren't used at the same time, we can overflow in the
+ * other one.To keep things simple, we first assume linear space,
+ * then we relocate it to the final handler layout as needed.
+ */
+static u32 final_handler[64];
+
+/*
+ * Hazards
+ *
+ * From the IDT errata for the QED RM5230 (Nevada), processor revision 1.0:
+ * 2. A timing hazard exists for the TLBP instruction.
+ *
+ * stalling_instruction
+ * TLBP
+ *
+ * The JTLB is being read for the TLBP throughout the stall generated by the
+ * previous instruction. This is not really correct as the stalling instruction
+ * can modify the address used to access the JTLB. The failure symptom is that
+ * the TLBP instruction will use an address created for the stalling instruction
+ * and not the address held in C0_ENHI and thus report the wrong results.
+ *
+ * The software work-around is to not allow the instruction preceding the TLBP
+ * to stall - make it an NOP or some other instruction guaranteed not to stall.
+ *
+ * Errata 2 will not be fixed. This errata is also on the R5000.
+ *
+ * As if we MIPS hackers wouldn't know how to nop pipelines happy ...
+ */
+static void __maybe_unused build_tlb_probe_entry(u32 **p)
+{
+ switch (current_cpu_type()) {
+ /* Found by experiment: R4600 v2.0/R4700 needs this, too. */
+ case CPU_R4600:
+ case CPU_R4700:
+ case CPU_R5000:
+ case CPU_NEVADA:
+ uasm_i_nop(p);
+ uasm_i_tlbp(p);
+ break;
+
+ default:
+ uasm_i_tlbp(p);
+ break;
+ }
+}
+
+void build_tlb_write_entry(u32 **p, struct uasm_label **l,
+ struct uasm_reloc **r,
+ enum tlb_write_entry wmode)
+{
+ void(*tlbw)(u32 **) = NULL;
+
+ switch (wmode) {
+ case tlb_random: tlbw = uasm_i_tlbwr; break;
+ case tlb_indexed: tlbw = uasm_i_tlbwi; break;
+ }
+
+ if (cpu_has_mips_r2_r6) {
+ if (cpu_has_mips_r2_exec_hazard)
+ uasm_i_ehb(p);
+ tlbw(p);
+ return;
+ }
+
+ switch (current_cpu_type()) {
+ case CPU_R4000PC:
+ case CPU_R4000SC:
+ case CPU_R4000MC:
+ case CPU_R4400PC:
+ case CPU_R4400SC:
+ case CPU_R4400MC:
+ /*
+ * This branch uses up a mtc0 hazard nop slot and saves
+ * two nops after the tlbw instruction.
+ */
+ uasm_bgezl_hazard(p, r, hazard_instance);
+ tlbw(p);
+ uasm_bgezl_label(l, p, hazard_instance);
+ hazard_instance++;
+ uasm_i_nop(p);
+ break;
+
+ case CPU_R4600:
+ case CPU_R4700:
+ uasm_i_nop(p);
+ tlbw(p);
+ uasm_i_nop(p);
+ break;
+
+ case CPU_R5000:
+ case CPU_NEVADA:
+ uasm_i_nop(p); /* QED specifies 2 nops hazard */
+ uasm_i_nop(p); /* QED specifies 2 nops hazard */
+ tlbw(p);
+ break;
+
+ case CPU_R4300:
+ case CPU_5KC:
+ case CPU_TX49XX:
+ case CPU_PR4450:
+ uasm_i_nop(p);
+ tlbw(p);
+ break;
+
+ case CPU_R10000:
+ case CPU_R12000:
+ case CPU_R14000:
+ case CPU_R16000:
+ case CPU_4KC:
+ case CPU_4KEC:
+ case CPU_M14KC:
+ case CPU_M14KEC:
+ case CPU_SB1:
+ case CPU_SB1A:
+ case CPU_4KSC:
+ case CPU_20KC:
+ case CPU_25KF:
+ case CPU_BMIPS32:
+ case CPU_BMIPS3300:
+ case CPU_BMIPS4350:
+ case CPU_BMIPS4380:
+ case CPU_BMIPS5000:
+ case CPU_LOONGSON2EF:
+ case CPU_LOONGSON64:
+ case CPU_R5500:
+ if (m4kc_tlbp_war())
+ uasm_i_nop(p);
+ fallthrough;
+ case CPU_ALCHEMY:
+ tlbw(p);
+ break;
+
+ case CPU_RM7000:
+ uasm_i_nop(p);
+ uasm_i_nop(p);
+ uasm_i_nop(p);
+ uasm_i_nop(p);
+ tlbw(p);
+ break;
+
+ case CPU_XBURST:
+ tlbw(p);
+ uasm_i_nop(p);
+ break;
+
+ default:
+ panic("No TLB refill handler yet (CPU type: %d)",
+ current_cpu_type());
+ break;
+ }
+}
+EXPORT_SYMBOL_GPL(build_tlb_write_entry);
+
+static __maybe_unused void build_convert_pte_to_entrylo(u32 **p,
+ unsigned int reg)
+{
+ if (_PAGE_GLOBAL_SHIFT == 0) {
+ /* pte_t is already in EntryLo format */
+ return;
+ }
+
+ if (cpu_has_rixi && _PAGE_NO_EXEC != 0) {
+ if (fill_includes_sw_bits) {
+ UASM_i_ROTR(p, reg, reg, ilog2(_PAGE_GLOBAL));
+ } else {
+ UASM_i_SRL(p, reg, reg, ilog2(_PAGE_NO_EXEC));
+ UASM_i_ROTR(p, reg, reg,
+ ilog2(_PAGE_GLOBAL) - ilog2(_PAGE_NO_EXEC));
+ }
+ } else {
+#ifdef CONFIG_PHYS_ADDR_T_64BIT
+ uasm_i_dsrl_safe(p, reg, reg, ilog2(_PAGE_GLOBAL));
+#else
+ UASM_i_SRL(p, reg, reg, ilog2(_PAGE_GLOBAL));
+#endif
+ }
+}
+
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+
+static void build_restore_pagemask(u32 **p, struct uasm_reloc **r,
+ unsigned int tmp, enum label_id lid,
+ int restore_scratch)
+{
+ if (restore_scratch) {
+ /*
+ * Ensure the MFC0 below observes the value written to the
+ * KScratch register by the prior MTC0.
+ */
+ if (scratch_reg >= 0)
+ uasm_i_ehb(p);
+
+ /* Reset default page size */
+ if (PM_DEFAULT_MASK >> 16) {
+ uasm_i_lui(p, tmp, PM_DEFAULT_MASK >> 16);
+ uasm_i_ori(p, tmp, tmp, PM_DEFAULT_MASK & 0xffff);
+ uasm_i_mtc0(p, tmp, C0_PAGEMASK);
+ uasm_il_b(p, r, lid);
+ } else if (PM_DEFAULT_MASK) {
+ uasm_i_ori(p, tmp, 0, PM_DEFAULT_MASK);
+ uasm_i_mtc0(p, tmp, C0_PAGEMASK);
+ uasm_il_b(p, r, lid);
+ } else {
+ uasm_i_mtc0(p, 0, C0_PAGEMASK);
+ uasm_il_b(p, r, lid);
+ }
+ if (scratch_reg >= 0)
+ UASM_i_MFC0(p, 1, c0_kscratch(), scratch_reg);
+ else
+ UASM_i_LW(p, 1, scratchpad_offset(0), 0);
+ } else {
+ /* Reset default page size */
+ if (PM_DEFAULT_MASK >> 16) {
+ uasm_i_lui(p, tmp, PM_DEFAULT_MASK >> 16);
+ uasm_i_ori(p, tmp, tmp, PM_DEFAULT_MASK & 0xffff);
+ uasm_il_b(p, r, lid);
+ uasm_i_mtc0(p, tmp, C0_PAGEMASK);
+ } else if (PM_DEFAULT_MASK) {
+ uasm_i_ori(p, tmp, 0, PM_DEFAULT_MASK);
+ uasm_il_b(p, r, lid);
+ uasm_i_mtc0(p, tmp, C0_PAGEMASK);
+ } else {
+ uasm_il_b(p, r, lid);
+ uasm_i_mtc0(p, 0, C0_PAGEMASK);
+ }
+ }
+}
+
+static void build_huge_tlb_write_entry(u32 **p, struct uasm_label **l,
+ struct uasm_reloc **r,
+ unsigned int tmp,
+ enum tlb_write_entry wmode,
+ int restore_scratch)
+{
+ /* Set huge page tlb entry size */
+ uasm_i_lui(p, tmp, PM_HUGE_MASK >> 16);
+ uasm_i_ori(p, tmp, tmp, PM_HUGE_MASK & 0xffff);
+ uasm_i_mtc0(p, tmp, C0_PAGEMASK);
+
+ build_tlb_write_entry(p, l, r, wmode);
+
+ build_restore_pagemask(p, r, tmp, label_leave, restore_scratch);
+}
+
+/*
+ * Check if Huge PTE is present, if so then jump to LABEL.
+ */
+static void
+build_is_huge_pte(u32 **p, struct uasm_reloc **r, unsigned int tmp,
+ unsigned int pmd, int lid)
+{
+ UASM_i_LW(p, tmp, 0, pmd);
+ if (use_bbit_insns()) {
+ uasm_il_bbit1(p, r, tmp, ilog2(_PAGE_HUGE), lid);
+ } else {
+ uasm_i_andi(p, tmp, tmp, _PAGE_HUGE);
+ uasm_il_bnez(p, r, tmp, lid);
+ }
+}
+
+static void build_huge_update_entries(u32 **p, unsigned int pte,
+ unsigned int tmp)
+{
+ int small_sequence;
+
+ /*
+ * A huge PTE describes an area the size of the
+ * configured huge page size. This is twice the
+ * of the large TLB entry size we intend to use.
+ * A TLB entry half the size of the configured
+ * huge page size is configured into entrylo0
+ * and entrylo1 to cover the contiguous huge PTE
+ * address space.
+ */
+ small_sequence = (HPAGE_SIZE >> 7) < 0x10000;
+
+ /* We can clobber tmp. It isn't used after this.*/
+ if (!small_sequence)
+ uasm_i_lui(p, tmp, HPAGE_SIZE >> (7 + 16));
+
+ build_convert_pte_to_entrylo(p, pte);
+ UASM_i_MTC0(p, pte, C0_ENTRYLO0); /* load it */
+ /* convert to entrylo1 */
+ if (small_sequence)
+ UASM_i_ADDIU(p, pte, pte, HPAGE_SIZE >> 7);
+ else
+ UASM_i_ADDU(p, pte, pte, tmp);
+
+ UASM_i_MTC0(p, pte, C0_ENTRYLO1); /* load it */
+}
+
+static void build_huge_handler_tail(u32 **p, struct uasm_reloc **r,
+ struct uasm_label **l,
+ unsigned int pte,
+ unsigned int ptr,
+ unsigned int flush)
+{
+#ifdef CONFIG_SMP
+ UASM_i_SC(p, pte, 0, ptr);
+ uasm_il_beqz(p, r, pte, label_tlb_huge_update);
+ UASM_i_LW(p, pte, 0, ptr); /* Needed because SC killed our PTE */
+#else
+ UASM_i_SW(p, pte, 0, ptr);
+#endif
+ if (cpu_has_ftlb && flush) {
+ BUG_ON(!cpu_has_tlbinv);
+
+ UASM_i_MFC0(p, ptr, C0_ENTRYHI);
+ uasm_i_ori(p, ptr, ptr, MIPS_ENTRYHI_EHINV);
+ UASM_i_MTC0(p, ptr, C0_ENTRYHI);
+ build_tlb_write_entry(p, l, r, tlb_indexed);
+
+ uasm_i_xori(p, ptr, ptr, MIPS_ENTRYHI_EHINV);
+ UASM_i_MTC0(p, ptr, C0_ENTRYHI);
+ build_huge_update_entries(p, pte, ptr);
+ build_huge_tlb_write_entry(p, l, r, pte, tlb_random, 0);
+
+ return;
+ }
+
+ build_huge_update_entries(p, pte, ptr);
+ build_huge_tlb_write_entry(p, l, r, pte, tlb_indexed, 0);
+}
+#endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
+
+#ifdef CONFIG_64BIT
+/*
+ * TMP and PTR are scratch.
+ * TMP will be clobbered, PTR will hold the pmd entry.
+ */
+void build_get_pmde64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
+ unsigned int tmp, unsigned int ptr)
+{
+#ifndef CONFIG_MIPS_PGD_C0_CONTEXT
+ long pgdc = (long)pgd_current;
+#endif
+ /*
+ * The vmalloc handling is not in the hotpath.
+ */
+ uasm_i_dmfc0(p, tmp, C0_BADVADDR);
+
+ if (check_for_high_segbits) {
+ /*
+ * The kernel currently implicitely assumes that the
+ * MIPS SEGBITS parameter for the processor is
+ * (PGDIR_SHIFT+PGDIR_BITS) or less, and will never
+ * allocate virtual addresses outside the maximum
+ * range for SEGBITS = (PGDIR_SHIFT+PGDIR_BITS). But
+ * that doesn't prevent user code from accessing the
+ * higher xuseg addresses. Here, we make sure that
+ * everything but the lower xuseg addresses goes down
+ * the module_alloc/vmalloc path.
+ */
+ uasm_i_dsrl_safe(p, ptr, tmp, PGDIR_SHIFT + PGD_TABLE_ORDER + PAGE_SHIFT - 3);
+ uasm_il_bnez(p, r, ptr, label_vmalloc);
+ } else {
+ uasm_il_bltz(p, r, tmp, label_vmalloc);
+ }
+ /* No uasm_i_nop needed here, since the next insn doesn't touch TMP. */
+
+ if (pgd_reg != -1) {
+ /* pgd is in pgd_reg */
+ if (cpu_has_ldpte)
+ UASM_i_MFC0(p, ptr, C0_PWBASE);
+ else
+ UASM_i_MFC0(p, ptr, c0_kscratch(), pgd_reg);
+ } else {
+#if defined(CONFIG_MIPS_PGD_C0_CONTEXT)
+ /*
+ * &pgd << 11 stored in CONTEXT [23..63].
+ */
+ UASM_i_MFC0(p, ptr, C0_CONTEXT);
+
+ /* Clear lower 23 bits of context. */
+ uasm_i_dins(p, ptr, 0, 0, 23);
+
+ /* insert bit[63:59] of CAC_BASE into bit[11:6] of ptr */
+ uasm_i_ori(p, ptr, ptr, ((u64)(CAC_BASE) >> 53));
+ uasm_i_drotr(p, ptr, ptr, 11);
+#elif defined(CONFIG_SMP)
+ UASM_i_CPUID_MFC0(p, ptr, SMP_CPUID_REG);
+ uasm_i_dsrl_safe(p, ptr, ptr, SMP_CPUID_PTRSHIFT);
+ UASM_i_LA_mostly(p, tmp, pgdc);
+ uasm_i_daddu(p, ptr, ptr, tmp);
+ uasm_i_dmfc0(p, tmp, C0_BADVADDR);
+ uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
+#else
+ UASM_i_LA_mostly(p, ptr, pgdc);
+ uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
+#endif
+ }
+
+ uasm_l_vmalloc_done(l, *p);
+
+ /* get pgd offset in bytes */
+ uasm_i_dsrl_safe(p, tmp, tmp, PGDIR_SHIFT - 3);
+
+ uasm_i_andi(p, tmp, tmp, (PTRS_PER_PGD - 1)<<3);
+ uasm_i_daddu(p, ptr, ptr, tmp); /* add in pgd offset */
+#ifndef __PAGETABLE_PUD_FOLDED
+ uasm_i_dmfc0(p, tmp, C0_BADVADDR); /* get faulting address */
+ uasm_i_ld(p, ptr, 0, ptr); /* get pud pointer */
+ uasm_i_dsrl_safe(p, tmp, tmp, PUD_SHIFT - 3); /* get pud offset in bytes */
+ uasm_i_andi(p, tmp, tmp, (PTRS_PER_PUD - 1) << 3);
+ uasm_i_daddu(p, ptr, ptr, tmp); /* add in pud offset */
+#endif
+#ifndef __PAGETABLE_PMD_FOLDED
+ uasm_i_dmfc0(p, tmp, C0_BADVADDR); /* get faulting address */
+ uasm_i_ld(p, ptr, 0, ptr); /* get pmd pointer */
+ uasm_i_dsrl_safe(p, tmp, tmp, PMD_SHIFT-3); /* get pmd offset in bytes */
+ uasm_i_andi(p, tmp, tmp, (PTRS_PER_PMD - 1)<<3);
+ uasm_i_daddu(p, ptr, ptr, tmp); /* add in pmd offset */
+#endif
+}
+EXPORT_SYMBOL_GPL(build_get_pmde64);
+
+/*
+ * BVADDR is the faulting address, PTR is scratch.
+ * PTR will hold the pgd for vmalloc.
+ */
+static void
+build_get_pgd_vmalloc64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
+ unsigned int bvaddr, unsigned int ptr,
+ enum vmalloc64_mode mode)
+{
+ long swpd = (long)swapper_pg_dir;
+ int single_insn_swpd;
+ int did_vmalloc_branch = 0;
+
+ single_insn_swpd = uasm_in_compat_space_p(swpd) && !uasm_rel_lo(swpd);
+
+ uasm_l_vmalloc(l, *p);
+
+ if (mode != not_refill && check_for_high_segbits) {
+ if (single_insn_swpd) {
+ uasm_il_bltz(p, r, bvaddr, label_vmalloc_done);
+ uasm_i_lui(p, ptr, uasm_rel_hi(swpd));
+ did_vmalloc_branch = 1;
+ /* fall through */
+ } else {
+ uasm_il_bgez(p, r, bvaddr, label_large_segbits_fault);
+ }
+ }
+ if (!did_vmalloc_branch) {
+ if (single_insn_swpd) {
+ uasm_il_b(p, r, label_vmalloc_done);
+ uasm_i_lui(p, ptr, uasm_rel_hi(swpd));
+ } else {
+ UASM_i_LA_mostly(p, ptr, swpd);
+ uasm_il_b(p, r, label_vmalloc_done);
+ if (uasm_in_compat_space_p(swpd))
+ uasm_i_addiu(p, ptr, ptr, uasm_rel_lo(swpd));
+ else
+ uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(swpd));
+ }
+ }
+ if (mode != not_refill && check_for_high_segbits) {
+ uasm_l_large_segbits_fault(l, *p);
+
+ if (mode == refill_scratch && scratch_reg >= 0)
+ uasm_i_ehb(p);
+
+ /*
+ * We get here if we are an xsseg address, or if we are
+ * an xuseg address above (PGDIR_SHIFT+PGDIR_BITS) boundary.
+ *
+ * Ignoring xsseg (assume disabled so would generate
+ * (address errors?), the only remaining possibility
+ * is the upper xuseg addresses. On processors with
+ * TLB_SEGBITS <= PGDIR_SHIFT+PGDIR_BITS, these
+ * addresses would have taken an address error. We try
+ * to mimic that here by taking a load/istream page
+ * fault.
+ */
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(p, 0);
+ UASM_i_LA(p, ptr, (unsigned long)tlb_do_page_fault_0);
+ uasm_i_jr(p, ptr);
+
+ if (mode == refill_scratch) {
+ if (scratch_reg >= 0)
+ UASM_i_MFC0(p, 1, c0_kscratch(), scratch_reg);
+ else
+ UASM_i_LW(p, 1, scratchpad_offset(0), 0);
+ } else {
+ uasm_i_nop(p);
+ }
+ }
+}
+
+#else /* !CONFIG_64BIT */
+
+/*
+ * TMP and PTR are scratch.
+ * TMP will be clobbered, PTR will hold the pgd entry.
+ */
+void build_get_pgde32(u32 **p, unsigned int tmp, unsigned int ptr)
+{
+ if (pgd_reg != -1) {
+ /* pgd is in pgd_reg */
+ uasm_i_mfc0(p, ptr, c0_kscratch(), pgd_reg);
+ uasm_i_mfc0(p, tmp, C0_BADVADDR); /* get faulting address */
+ } else {
+ long pgdc = (long)pgd_current;
+
+ /* 32 bit SMP has smp_processor_id() stored in CONTEXT. */
+#ifdef CONFIG_SMP
+ uasm_i_mfc0(p, ptr, SMP_CPUID_REG);
+ UASM_i_LA_mostly(p, tmp, pgdc);
+ uasm_i_srl(p, ptr, ptr, SMP_CPUID_PTRSHIFT);
+ uasm_i_addu(p, ptr, tmp, ptr);
+#else
+ UASM_i_LA_mostly(p, ptr, pgdc);
+#endif
+ uasm_i_mfc0(p, tmp, C0_BADVADDR); /* get faulting address */
+ uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
+ }
+ uasm_i_srl(p, tmp, tmp, PGDIR_SHIFT); /* get pgd only bits */
+ uasm_i_sll(p, tmp, tmp, PGD_T_LOG2);
+ uasm_i_addu(p, ptr, ptr, tmp); /* add in pgd offset */
+}
+EXPORT_SYMBOL_GPL(build_get_pgde32);
+
+#endif /* !CONFIG_64BIT */
+
+static void build_adjust_context(u32 **p, unsigned int ctx)
+{
+ unsigned int shift = 4 - (PTE_T_LOG2 + 1) + PAGE_SHIFT - 12;
+ unsigned int mask = (PTRS_PER_PTE / 2 - 1) << (PTE_T_LOG2 + 1);
+
+ if (shift)
+ UASM_i_SRL(p, ctx, ctx, shift);
+ uasm_i_andi(p, ctx, ctx, mask);
+}
+
+void build_get_ptep(u32 **p, unsigned int tmp, unsigned int ptr)
+{
+ /*
+ * Bug workaround for the Nevada. It seems as if under certain
+ * circumstances the move from cp0_context might produce a
+ * bogus result when the mfc0 instruction and its consumer are
+ * in a different cacheline or a load instruction, probably any
+ * memory reference, is between them.
+ */
+ switch (current_cpu_type()) {
+ case CPU_NEVADA:
+ UASM_i_LW(p, ptr, 0, ptr);
+ GET_CONTEXT(p, tmp); /* get context reg */
+ break;
+
+ default:
+ GET_CONTEXT(p, tmp); /* get context reg */
+ UASM_i_LW(p, ptr, 0, ptr);
+ break;
+ }
+
+ build_adjust_context(p, tmp);
+ UASM_i_ADDU(p, ptr, ptr, tmp); /* add in offset */
+}
+EXPORT_SYMBOL_GPL(build_get_ptep);
+
+void build_update_entries(u32 **p, unsigned int tmp, unsigned int ptep)
+{
+ int pte_off_even = 0;
+ int pte_off_odd = sizeof(pte_t);
+
+#if defined(CONFIG_CPU_MIPS32) && defined(CONFIG_PHYS_ADDR_T_64BIT)
+ /* The low 32 bits of EntryLo is stored in pte_high */
+ pte_off_even += offsetof(pte_t, pte_high);
+ pte_off_odd += offsetof(pte_t, pte_high);
+#endif
+
+ if (IS_ENABLED(CONFIG_XPA)) {
+ uasm_i_lw(p, tmp, pte_off_even, ptep); /* even pte */
+ UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL));
+ UASM_i_MTC0(p, tmp, C0_ENTRYLO0);
+
+ if (cpu_has_xpa && !mips_xpa_disabled) {
+ uasm_i_lw(p, tmp, 0, ptep);
+ uasm_i_ext(p, tmp, tmp, 0, 24);
+ uasm_i_mthc0(p, tmp, C0_ENTRYLO0);
+ }
+
+ uasm_i_lw(p, tmp, pte_off_odd, ptep); /* odd pte */
+ UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL));
+ UASM_i_MTC0(p, tmp, C0_ENTRYLO1);
+
+ if (cpu_has_xpa && !mips_xpa_disabled) {
+ uasm_i_lw(p, tmp, sizeof(pte_t), ptep);
+ uasm_i_ext(p, tmp, tmp, 0, 24);
+ uasm_i_mthc0(p, tmp, C0_ENTRYLO1);
+ }
+ return;
+ }
+
+ UASM_i_LW(p, tmp, pte_off_even, ptep); /* get even pte */
+ UASM_i_LW(p, ptep, pte_off_odd, ptep); /* get odd pte */
+ if (r45k_bvahwbug())
+ build_tlb_probe_entry(p);
+ build_convert_pte_to_entrylo(p, tmp);
+ if (r4k_250MHZhwbug())
+ UASM_i_MTC0(p, 0, C0_ENTRYLO0);
+ UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
+ build_convert_pte_to_entrylo(p, ptep);
+ if (r45k_bvahwbug())
+ uasm_i_mfc0(p, tmp, C0_INDEX);
+ if (r4k_250MHZhwbug())
+ UASM_i_MTC0(p, 0, C0_ENTRYLO1);
+ UASM_i_MTC0(p, ptep, C0_ENTRYLO1); /* load it */
+}
+EXPORT_SYMBOL_GPL(build_update_entries);
+
+struct mips_huge_tlb_info {
+ int huge_pte;
+ int restore_scratch;
+ bool need_reload_pte;
+};
+
+static struct mips_huge_tlb_info
+build_fast_tlb_refill_handler (u32 **p, struct uasm_label **l,
+ struct uasm_reloc **r, unsigned int tmp,
+ unsigned int ptr, int c0_scratch_reg)
+{
+ struct mips_huge_tlb_info rv;
+ unsigned int even, odd;
+ int vmalloc_branch_delay_filled = 0;
+ const int scratch = 1; /* Our extra working register */
+
+ rv.huge_pte = scratch;
+ rv.restore_scratch = 0;
+ rv.need_reload_pte = false;
+
+ if (check_for_high_segbits) {
+ UASM_i_MFC0(p, tmp, C0_BADVADDR);
+
+ if (pgd_reg != -1)
+ UASM_i_MFC0(p, ptr, c0_kscratch(), pgd_reg);
+ else
+ UASM_i_MFC0(p, ptr, C0_CONTEXT);
+
+ if (c0_scratch_reg >= 0)
+ UASM_i_MTC0(p, scratch, c0_kscratch(), c0_scratch_reg);
+ else
+ UASM_i_SW(p, scratch, scratchpad_offset(0), 0);
+
+ uasm_i_dsrl_safe(p, scratch, tmp,
+ PGDIR_SHIFT + PGD_TABLE_ORDER + PAGE_SHIFT - 3);
+ uasm_il_bnez(p, r, scratch, label_vmalloc);
+
+ if (pgd_reg == -1) {
+ vmalloc_branch_delay_filled = 1;
+ /* Clear lower 23 bits of context. */
+ uasm_i_dins(p, ptr, 0, 0, 23);
+ }
+ } else {
+ if (pgd_reg != -1)
+ UASM_i_MFC0(p, ptr, c0_kscratch(), pgd_reg);
+ else
+ UASM_i_MFC0(p, ptr, C0_CONTEXT);
+
+ UASM_i_MFC0(p, tmp, C0_BADVADDR);
+
+ if (c0_scratch_reg >= 0)
+ UASM_i_MTC0(p, scratch, c0_kscratch(), c0_scratch_reg);
+ else
+ UASM_i_SW(p, scratch, scratchpad_offset(0), 0);
+
+ if (pgd_reg == -1)
+ /* Clear lower 23 bits of context. */
+ uasm_i_dins(p, ptr, 0, 0, 23);
+
+ uasm_il_bltz(p, r, tmp, label_vmalloc);
+ }
+
+ if (pgd_reg == -1) {
+ vmalloc_branch_delay_filled = 1;
+ /* insert bit[63:59] of CAC_BASE into bit[11:6] of ptr */
+ uasm_i_ori(p, ptr, ptr, ((u64)(CAC_BASE) >> 53));
+
+ uasm_i_drotr(p, ptr, ptr, 11);
+ }
+
+#ifdef __PAGETABLE_PMD_FOLDED
+#define LOC_PTEP scratch
+#else
+#define LOC_PTEP ptr
+#endif
+
+ if (!vmalloc_branch_delay_filled)
+ /* get pgd offset in bytes */
+ uasm_i_dsrl_safe(p, scratch, tmp, PGDIR_SHIFT - 3);
+
+ uasm_l_vmalloc_done(l, *p);
+
+ /*
+ * tmp ptr
+ * fall-through case = badvaddr *pgd_current
+ * vmalloc case = badvaddr swapper_pg_dir
+ */
+
+ if (vmalloc_branch_delay_filled)
+ /* get pgd offset in bytes */
+ uasm_i_dsrl_safe(p, scratch, tmp, PGDIR_SHIFT - 3);
+
+#ifdef __PAGETABLE_PMD_FOLDED
+ GET_CONTEXT(p, tmp); /* get context reg */
+#endif
+ uasm_i_andi(p, scratch, scratch, (PTRS_PER_PGD - 1) << 3);
+
+ if (use_lwx_insns()) {
+ UASM_i_LWX(p, LOC_PTEP, scratch, ptr);
+ } else {
+ uasm_i_daddu(p, ptr, ptr, scratch); /* add in pgd offset */
+ uasm_i_ld(p, LOC_PTEP, 0, ptr); /* get pmd pointer */
+ }
+
+#ifndef __PAGETABLE_PUD_FOLDED
+ /* get pud offset in bytes */
+ uasm_i_dsrl_safe(p, scratch, tmp, PUD_SHIFT - 3);
+ uasm_i_andi(p, scratch, scratch, (PTRS_PER_PUD - 1) << 3);
+
+ if (use_lwx_insns()) {
+ UASM_i_LWX(p, ptr, scratch, ptr);
+ } else {
+ uasm_i_daddu(p, ptr, ptr, scratch); /* add in pmd offset */
+ UASM_i_LW(p, ptr, 0, ptr);
+ }
+ /* ptr contains a pointer to PMD entry */
+ /* tmp contains the address */
+#endif
+
+#ifndef __PAGETABLE_PMD_FOLDED
+ /* get pmd offset in bytes */
+ uasm_i_dsrl_safe(p, scratch, tmp, PMD_SHIFT - 3);
+ uasm_i_andi(p, scratch, scratch, (PTRS_PER_PMD - 1) << 3);
+ GET_CONTEXT(p, tmp); /* get context reg */
+
+ if (use_lwx_insns()) {
+ UASM_i_LWX(p, scratch, scratch, ptr);
+ } else {
+ uasm_i_daddu(p, ptr, ptr, scratch); /* add in pmd offset */
+ UASM_i_LW(p, scratch, 0, ptr);
+ }
+#endif
+ /* Adjust the context during the load latency. */
+ build_adjust_context(p, tmp);
+
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ uasm_il_bbit1(p, r, scratch, ilog2(_PAGE_HUGE), label_tlb_huge_update);
+ /*
+ * The in the LWX case we don't want to do the load in the
+ * delay slot. It cannot issue in the same cycle and may be
+ * speculative and unneeded.
+ */
+ if (use_lwx_insns())
+ uasm_i_nop(p);
+#endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
+
+
+ /* build_update_entries */
+ if (use_lwx_insns()) {
+ even = ptr;
+ odd = tmp;
+ UASM_i_LWX(p, even, scratch, tmp);
+ UASM_i_ADDIU(p, tmp, tmp, sizeof(pte_t));
+ UASM_i_LWX(p, odd, scratch, tmp);
+ } else {
+ UASM_i_ADDU(p, ptr, scratch, tmp); /* add in offset */
+ even = tmp;
+ odd = ptr;
+ UASM_i_LW(p, even, 0, ptr); /* get even pte */
+ UASM_i_LW(p, odd, sizeof(pte_t), ptr); /* get odd pte */
+ }
+ if (cpu_has_rixi) {
+ uasm_i_drotr(p, even, even, ilog2(_PAGE_GLOBAL));
+ UASM_i_MTC0(p, even, C0_ENTRYLO0); /* load it */
+ uasm_i_drotr(p, odd, odd, ilog2(_PAGE_GLOBAL));
+ } else {
+ uasm_i_dsrl_safe(p, even, even, ilog2(_PAGE_GLOBAL));
+ UASM_i_MTC0(p, even, C0_ENTRYLO0); /* load it */
+ uasm_i_dsrl_safe(p, odd, odd, ilog2(_PAGE_GLOBAL));
+ }
+ UASM_i_MTC0(p, odd, C0_ENTRYLO1); /* load it */
+
+ if (c0_scratch_reg >= 0) {
+ uasm_i_ehb(p);
+ UASM_i_MFC0(p, scratch, c0_kscratch(), c0_scratch_reg);
+ build_tlb_write_entry(p, l, r, tlb_random);
+ uasm_l_leave(l, *p);
+ rv.restore_scratch = 1;
+ } else if (PAGE_SHIFT == 14 || PAGE_SHIFT == 13) {
+ build_tlb_write_entry(p, l, r, tlb_random);
+ uasm_l_leave(l, *p);
+ UASM_i_LW(p, scratch, scratchpad_offset(0), 0);
+ } else {
+ UASM_i_LW(p, scratch, scratchpad_offset(0), 0);
+ build_tlb_write_entry(p, l, r, tlb_random);
+ uasm_l_leave(l, *p);
+ rv.restore_scratch = 1;
+ }
+
+ uasm_i_eret(p); /* return from trap */
+
+ return rv;
+}
+
+/*
+ * For a 64-bit kernel, we are using the 64-bit XTLB refill exception
+ * because EXL == 0. If we wrap, we can also use the 32 instruction
+ * slots before the XTLB refill exception handler which belong to the
+ * unused TLB refill exception.
+ */
+#define MIPS64_REFILL_INSNS 32
+
+static void build_r4000_tlb_refill_handler(void)
+{
+ u32 *p = tlb_handler;
+ struct uasm_label *l = labels;
+ struct uasm_reloc *r = relocs;
+ u32 *f;
+ unsigned int final_len;
+ struct mips_huge_tlb_info htlb_info __maybe_unused;
+ enum vmalloc64_mode vmalloc_mode __maybe_unused;
+
+ memset(tlb_handler, 0, sizeof(tlb_handler));
+ memset(labels, 0, sizeof(labels));
+ memset(relocs, 0, sizeof(relocs));
+ memset(final_handler, 0, sizeof(final_handler));
+
+ if (IS_ENABLED(CONFIG_64BIT) && (scratch_reg >= 0 || scratchpad_available()) && use_bbit_insns()) {
+ htlb_info = build_fast_tlb_refill_handler(&p, &l, &r, K0, K1,
+ scratch_reg);
+ vmalloc_mode = refill_scratch;
+ } else {
+ htlb_info.huge_pte = K0;
+ htlb_info.restore_scratch = 0;
+ htlb_info.need_reload_pte = true;
+ vmalloc_mode = refill_noscratch;
+ /*
+ * create the plain linear handler
+ */
+ if (bcm1250_m3_war()) {
+ unsigned int segbits = 44;
+
+ uasm_i_dmfc0(&p, K0, C0_BADVADDR);
+ uasm_i_dmfc0(&p, K1, C0_ENTRYHI);
+ uasm_i_xor(&p, K0, K0, K1);
+ uasm_i_dsrl_safe(&p, K1, K0, 62);
+ uasm_i_dsrl_safe(&p, K0, K0, 12 + 1);
+ uasm_i_dsll_safe(&p, K0, K0, 64 + 12 + 1 - segbits);
+ uasm_i_or(&p, K0, K0, K1);
+ uasm_il_bnez(&p, &r, K0, label_leave);
+ /* No need for uasm_i_nop */
+ }
+
+#ifdef CONFIG_64BIT
+ build_get_pmde64(&p, &l, &r, K0, K1); /* get pmd in K1 */
+#else
+ build_get_pgde32(&p, K0, K1); /* get pgd in K1 */
+#endif
+
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ build_is_huge_pte(&p, &r, K0, K1, label_tlb_huge_update);
+#endif
+
+ build_get_ptep(&p, K0, K1);
+ build_update_entries(&p, K0, K1);
+ build_tlb_write_entry(&p, &l, &r, tlb_random);
+ uasm_l_leave(&l, p);
+ uasm_i_eret(&p); /* return from trap */
+ }
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ uasm_l_tlb_huge_update(&l, p);
+ if (htlb_info.need_reload_pte)
+ UASM_i_LW(&p, htlb_info.huge_pte, 0, K1);
+ build_huge_update_entries(&p, htlb_info.huge_pte, K1);
+ build_huge_tlb_write_entry(&p, &l, &r, K0, tlb_random,
+ htlb_info.restore_scratch);
+#endif
+
+#ifdef CONFIG_64BIT
+ build_get_pgd_vmalloc64(&p, &l, &r, K0, K1, vmalloc_mode);
+#endif
+
+ /*
+ * Overflow check: For the 64bit handler, we need at least one
+ * free instruction slot for the wrap-around branch. In worst
+ * case, if the intended insertion point is a delay slot, we
+ * need three, with the second nop'ed and the third being
+ * unused.
+ */
+ switch (boot_cpu_type()) {
+ default:
+ if (sizeof(long) == 4) {
+ fallthrough;
+ case CPU_LOONGSON2EF:
+ /* Loongson2 ebase is different than r4k, we have more space */
+ if ((p - tlb_handler) > 64)
+ panic("TLB refill handler space exceeded");
+ /*
+ * Now fold the handler in the TLB refill handler space.
+ */
+ f = final_handler;
+ /* Simplest case, just copy the handler. */
+ uasm_copy_handler(relocs, labels, tlb_handler, p, f);
+ final_len = p - tlb_handler;
+ break;
+ } else {
+ if (((p - tlb_handler) > (MIPS64_REFILL_INSNS * 2) - 1)
+ || (((p - tlb_handler) > (MIPS64_REFILL_INSNS * 2) - 3)
+ && uasm_insn_has_bdelay(relocs,
+ tlb_handler + MIPS64_REFILL_INSNS - 3)))
+ panic("TLB refill handler space exceeded");
+ /*
+ * Now fold the handler in the TLB refill handler space.
+ */
+ f = final_handler + MIPS64_REFILL_INSNS;
+ if ((p - tlb_handler) <= MIPS64_REFILL_INSNS) {
+ /* Just copy the handler. */
+ uasm_copy_handler(relocs, labels, tlb_handler, p, f);
+ final_len = p - tlb_handler;
+ } else {
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ const enum label_id ls = label_tlb_huge_update;
+#else
+ const enum label_id ls = label_vmalloc;
+#endif
+ u32 *split;
+ int ov = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(labels) && labels[i].lab != ls; i++)
+ ;
+ BUG_ON(i == ARRAY_SIZE(labels));
+ split = labels[i].addr;
+
+ /*
+ * See if we have overflown one way or the other.
+ */
+ if (split > tlb_handler + MIPS64_REFILL_INSNS ||
+ split < p - MIPS64_REFILL_INSNS)
+ ov = 1;
+
+ if (ov) {
+ /*
+ * Split two instructions before the end. One
+ * for the branch and one for the instruction
+ * in the delay slot.
+ */
+ split = tlb_handler + MIPS64_REFILL_INSNS - 2;
+
+ /*
+ * If the branch would fall in a delay slot,
+ * we must back up an additional instruction
+ * so that it is no longer in a delay slot.
+ */
+ if (uasm_insn_has_bdelay(relocs, split - 1))
+ split--;
+ }
+ /* Copy first part of the handler. */
+ uasm_copy_handler(relocs, labels, tlb_handler, split, f);
+ f += split - tlb_handler;
+
+ if (ov) {
+ /* Insert branch. */
+ uasm_l_split(&l, final_handler);
+ uasm_il_b(&f, &r, label_split);
+ if (uasm_insn_has_bdelay(relocs, split))
+ uasm_i_nop(&f);
+ else {
+ uasm_copy_handler(relocs, labels,
+ split, split + 1, f);
+ uasm_move_labels(labels, f, f + 1, -1);
+ f++;
+ split++;
+ }
+ }
+
+ /* Copy the rest of the handler. */
+ uasm_copy_handler(relocs, labels, split, p, final_handler);
+ final_len = (f - (final_handler + MIPS64_REFILL_INSNS)) +
+ (p - split);
+ }
+ }
+ break;
+ }
+
+ uasm_resolve_relocs(relocs, labels);
+ pr_debug("Wrote TLB refill handler (%u instructions).\n",
+ final_len);
+
+ memcpy((void *)ebase, final_handler, 0x100);
+ local_flush_icache_range(ebase, ebase + 0x100);
+ dump_handler("r4000_tlb_refill", (u32 *)ebase, (u32 *)(ebase + 0x100));
+}
+
+static void setup_pw(void)
+{
+ unsigned int pwctl;
+ unsigned long pgd_i, pgd_w;
+#ifndef __PAGETABLE_PMD_FOLDED
+ unsigned long pmd_i, pmd_w;
+#endif
+ unsigned long pt_i, pt_w;
+ unsigned long pte_i, pte_w;
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ unsigned long psn;
+
+ psn = ilog2(_PAGE_HUGE); /* bit used to indicate huge page */
+#endif
+ pgd_i = PGDIR_SHIFT; /* 1st level PGD */
+#ifndef __PAGETABLE_PMD_FOLDED
+ pgd_w = PGDIR_SHIFT - PMD_SHIFT + PGD_TABLE_ORDER;
+
+ pmd_i = PMD_SHIFT; /* 2nd level PMD */
+ pmd_w = PMD_SHIFT - PAGE_SHIFT;
+#else
+ pgd_w = PGDIR_SHIFT - PAGE_SHIFT + PGD_TABLE_ORDER;
+#endif
+
+ pt_i = PAGE_SHIFT; /* 3rd level PTE */
+ pt_w = PAGE_SHIFT - 3;
+
+ pte_i = ilog2(_PAGE_GLOBAL);
+ pte_w = 0;
+ pwctl = 1 << 30; /* Set PWDirExt */
+
+#ifndef __PAGETABLE_PMD_FOLDED
+ write_c0_pwfield(pgd_i << 24 | pmd_i << 12 | pt_i << 6 | pte_i);
+ write_c0_pwsize(1 << 30 | pgd_w << 24 | pmd_w << 12 | pt_w << 6 | pte_w);
+#else
+ write_c0_pwfield(pgd_i << 24 | pt_i << 6 | pte_i);
+ write_c0_pwsize(1 << 30 | pgd_w << 24 | pt_w << 6 | pte_w);
+#endif
+
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ pwctl |= (1 << 6 | psn);
+#endif
+ write_c0_pwctl(pwctl);
+ write_c0_kpgd((long)swapper_pg_dir);
+ kscratch_used_mask |= (1 << 7); /* KScratch6 is used for KPGD */
+}
+
+static void build_loongson3_tlb_refill_handler(void)
+{
+ u32 *p = tlb_handler;
+ struct uasm_label *l = labels;
+ struct uasm_reloc *r = relocs;
+
+ memset(labels, 0, sizeof(labels));
+ memset(relocs, 0, sizeof(relocs));
+ memset(tlb_handler, 0, sizeof(tlb_handler));
+
+ if (check_for_high_segbits) {
+ uasm_i_dmfc0(&p, K0, C0_BADVADDR);
+ uasm_i_dsrl_safe(&p, K1, K0, PGDIR_SHIFT + PGD_TABLE_ORDER + PAGE_SHIFT - 3);
+ uasm_il_beqz(&p, &r, K1, label_vmalloc);
+ uasm_i_nop(&p);
+
+ uasm_il_bgez(&p, &r, K0, label_large_segbits_fault);
+ uasm_i_nop(&p);
+ uasm_l_vmalloc(&l, p);
+ }
+
+ uasm_i_dmfc0(&p, K1, C0_PGD);
+
+ uasm_i_lddir(&p, K0, K1, 3); /* global page dir */
+#ifndef __PAGETABLE_PMD_FOLDED
+ uasm_i_lddir(&p, K1, K0, 1); /* middle page dir */
+#endif
+ uasm_i_ldpte(&p, K1, 0); /* even */
+ uasm_i_ldpte(&p, K1, 1); /* odd */
+ uasm_i_tlbwr(&p);
+
+ /* restore page mask */
+ if (PM_DEFAULT_MASK >> 16) {
+ uasm_i_lui(&p, K0, PM_DEFAULT_MASK >> 16);
+ uasm_i_ori(&p, K0, K0, PM_DEFAULT_MASK & 0xffff);
+ uasm_i_mtc0(&p, K0, C0_PAGEMASK);
+ } else if (PM_DEFAULT_MASK) {
+ uasm_i_ori(&p, K0, 0, PM_DEFAULT_MASK);
+ uasm_i_mtc0(&p, K0, C0_PAGEMASK);
+ } else {
+ uasm_i_mtc0(&p, 0, C0_PAGEMASK);
+ }
+
+ uasm_i_eret(&p);
+
+ if (check_for_high_segbits) {
+ uasm_l_large_segbits_fault(&l, p);
+ UASM_i_LA(&p, K1, (unsigned long)tlb_do_page_fault_0);
+ uasm_i_jr(&p, K1);
+ uasm_i_nop(&p);
+ }
+
+ uasm_resolve_relocs(relocs, labels);
+ memcpy((void *)(ebase + 0x80), tlb_handler, 0x80);
+ local_flush_icache_range(ebase + 0x80, ebase + 0x100);
+ dump_handler("loongson3_tlb_refill",
+ (u32 *)(ebase + 0x80), (u32 *)(ebase + 0x100));
+}
+
+static void build_setup_pgd(void)
+{
+ const int a0 = 4;
+ const int __maybe_unused a1 = 5;
+ const int __maybe_unused a2 = 6;
+ u32 *p = (u32 *)msk_isa16_mode((ulong)tlbmiss_handler_setup_pgd);
+#ifndef CONFIG_MIPS_PGD_C0_CONTEXT
+ long pgdc = (long)pgd_current;
+#endif
+
+ memset(p, 0, tlbmiss_handler_setup_pgd_end - (char *)p);
+ memset(labels, 0, sizeof(labels));
+ memset(relocs, 0, sizeof(relocs));
+ pgd_reg = allocate_kscratch();
+#ifdef CONFIG_MIPS_PGD_C0_CONTEXT
+ if (pgd_reg == -1) {
+ struct uasm_label *l = labels;
+ struct uasm_reloc *r = relocs;
+
+ /* PGD << 11 in c0_Context */
+ /*
+ * If it is a ckseg0 address, convert to a physical
+ * address. Shifting right by 29 and adding 4 will
+ * result in zero for these addresses.
+ *
+ */
+ UASM_i_SRA(&p, a1, a0, 29);
+ UASM_i_ADDIU(&p, a1, a1, 4);
+ uasm_il_bnez(&p, &r, a1, label_tlbl_goaround1);
+ uasm_i_nop(&p);
+ uasm_i_dinsm(&p, a0, 0, 29, 64 - 29);
+ uasm_l_tlbl_goaround1(&l, p);
+ UASM_i_SLL(&p, a0, a0, 11);
+ UASM_i_MTC0(&p, a0, C0_CONTEXT);
+ uasm_i_jr(&p, 31);
+ uasm_i_ehb(&p);
+ } else {
+ /* PGD in c0_KScratch */
+ if (cpu_has_ldpte)
+ UASM_i_MTC0(&p, a0, C0_PWBASE);
+ else
+ UASM_i_MTC0(&p, a0, c0_kscratch(), pgd_reg);
+ uasm_i_jr(&p, 31);
+ uasm_i_ehb(&p);
+ }
+#else
+#ifdef CONFIG_SMP
+ /* Save PGD to pgd_current[smp_processor_id()] */
+ UASM_i_CPUID_MFC0(&p, a1, SMP_CPUID_REG);
+ UASM_i_SRL_SAFE(&p, a1, a1, SMP_CPUID_PTRSHIFT);
+ UASM_i_LA_mostly(&p, a2, pgdc);
+ UASM_i_ADDU(&p, a2, a2, a1);
+ UASM_i_SW(&p, a0, uasm_rel_lo(pgdc), a2);
+#else
+ UASM_i_LA_mostly(&p, a2, pgdc);
+ UASM_i_SW(&p, a0, uasm_rel_lo(pgdc), a2);
+#endif /* SMP */
+
+ /* if pgd_reg is allocated, save PGD also to scratch register */
+ if (pgd_reg != -1) {
+ UASM_i_MTC0(&p, a0, c0_kscratch(), pgd_reg);
+ uasm_i_jr(&p, 31);
+ uasm_i_ehb(&p);
+ } else {
+ uasm_i_jr(&p, 31);
+ uasm_i_nop(&p);
+ }
+#endif
+ if (p >= (u32 *)tlbmiss_handler_setup_pgd_end)
+ panic("tlbmiss_handler_setup_pgd space exceeded");
+
+ uasm_resolve_relocs(relocs, labels);
+ pr_debug("Wrote tlbmiss_handler_setup_pgd (%u instructions).\n",
+ (unsigned int)(p - (u32 *)tlbmiss_handler_setup_pgd));
+
+ dump_handler("tlbmiss_handler", tlbmiss_handler_setup_pgd,
+ tlbmiss_handler_setup_pgd_end);
+}
+
+static void
+iPTE_LW(u32 **p, unsigned int pte, unsigned int ptr)
+{
+#ifdef CONFIG_SMP
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(p, 0);
+# ifdef CONFIG_PHYS_ADDR_T_64BIT
+ if (cpu_has_64bits)
+ uasm_i_lld(p, pte, 0, ptr);
+ else
+# endif
+ UASM_i_LL(p, pte, 0, ptr);
+#else
+# ifdef CONFIG_PHYS_ADDR_T_64BIT
+ if (cpu_has_64bits)
+ uasm_i_ld(p, pte, 0, ptr);
+ else
+# endif
+ UASM_i_LW(p, pte, 0, ptr);
+#endif
+}
+
+static void
+iPTE_SW(u32 **p, struct uasm_reloc **r, unsigned int pte, unsigned int ptr,
+ unsigned int mode, unsigned int scratch)
+{
+ unsigned int hwmode = mode & (_PAGE_VALID | _PAGE_DIRTY);
+ unsigned int swmode = mode & ~hwmode;
+
+ if (IS_ENABLED(CONFIG_XPA) && !cpu_has_64bits) {
+ uasm_i_lui(p, scratch, swmode >> 16);
+ uasm_i_or(p, pte, pte, scratch);
+ BUG_ON(swmode & 0xffff);
+ } else {
+ uasm_i_ori(p, pte, pte, mode);
+ }
+
+#ifdef CONFIG_SMP
+# ifdef CONFIG_PHYS_ADDR_T_64BIT
+ if (cpu_has_64bits)
+ uasm_i_scd(p, pte, 0, ptr);
+ else
+# endif
+ UASM_i_SC(p, pte, 0, ptr);
+
+ if (r10000_llsc_war())
+ uasm_il_beqzl(p, r, pte, label_smp_pgtable_change);
+ else
+ uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
+
+# ifdef CONFIG_PHYS_ADDR_T_64BIT
+ if (!cpu_has_64bits) {
+ /* no uasm_i_nop needed */
+ uasm_i_ll(p, pte, sizeof(pte_t) / 2, ptr);
+ uasm_i_ori(p, pte, pte, hwmode);
+ BUG_ON(hwmode & ~0xffff);
+ uasm_i_sc(p, pte, sizeof(pte_t) / 2, ptr);
+ uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
+ /* no uasm_i_nop needed */
+ uasm_i_lw(p, pte, 0, ptr);
+ } else
+ uasm_i_nop(p);
+# else
+ uasm_i_nop(p);
+# endif
+#else
+# ifdef CONFIG_PHYS_ADDR_T_64BIT
+ if (cpu_has_64bits)
+ uasm_i_sd(p, pte, 0, ptr);
+ else
+# endif
+ UASM_i_SW(p, pte, 0, ptr);
+
+# ifdef CONFIG_PHYS_ADDR_T_64BIT
+ if (!cpu_has_64bits) {
+ uasm_i_lw(p, pte, sizeof(pte_t) / 2, ptr);
+ uasm_i_ori(p, pte, pte, hwmode);
+ BUG_ON(hwmode & ~0xffff);
+ uasm_i_sw(p, pte, sizeof(pte_t) / 2, ptr);
+ uasm_i_lw(p, pte, 0, ptr);
+ }
+# endif
+#endif
+}
+
+/*
+ * Check if PTE is present, if not then jump to LABEL. PTR points to
+ * the page table where this PTE is located, PTE will be re-loaded
+ * with it's original value.
+ */
+static void
+build_pte_present(u32 **p, struct uasm_reloc **r,
+ int pte, int ptr, int scratch, enum label_id lid)
+{
+ int t = scratch >= 0 ? scratch : pte;
+ int cur = pte;
+
+ if (cpu_has_rixi) {
+ if (use_bbit_insns()) {
+ uasm_il_bbit0(p, r, pte, ilog2(_PAGE_PRESENT), lid);
+ uasm_i_nop(p);
+ } else {
+ if (_PAGE_PRESENT_SHIFT) {
+ uasm_i_srl(p, t, cur, _PAGE_PRESENT_SHIFT);
+ cur = t;
+ }
+ uasm_i_andi(p, t, cur, 1);
+ uasm_il_beqz(p, r, t, lid);
+ if (pte == t)
+ /* You lose the SMP race :-(*/
+ iPTE_LW(p, pte, ptr);
+ }
+ } else {
+ if (_PAGE_PRESENT_SHIFT) {
+ uasm_i_srl(p, t, cur, _PAGE_PRESENT_SHIFT);
+ cur = t;
+ }
+ uasm_i_andi(p, t, cur,
+ (_PAGE_PRESENT | _PAGE_NO_READ) >> _PAGE_PRESENT_SHIFT);
+ uasm_i_xori(p, t, t, _PAGE_PRESENT >> _PAGE_PRESENT_SHIFT);
+ uasm_il_bnez(p, r, t, lid);
+ if (pte == t)
+ /* You lose the SMP race :-(*/
+ iPTE_LW(p, pte, ptr);
+ }
+}
+
+/* Make PTE valid, store result in PTR. */
+static void
+build_make_valid(u32 **p, struct uasm_reloc **r, unsigned int pte,
+ unsigned int ptr, unsigned int scratch)
+{
+ unsigned int mode = _PAGE_VALID | _PAGE_ACCESSED;
+
+ iPTE_SW(p, r, pte, ptr, mode, scratch);
+}
+
+/*
+ * Check if PTE can be written to, if not branch to LABEL. Regardless
+ * restore PTE with value from PTR when done.
+ */
+static void
+build_pte_writable(u32 **p, struct uasm_reloc **r,
+ unsigned int pte, unsigned int ptr, int scratch,
+ enum label_id lid)
+{
+ int t = scratch >= 0 ? scratch : pte;
+ int cur = pte;
+
+ if (_PAGE_PRESENT_SHIFT) {
+ uasm_i_srl(p, t, cur, _PAGE_PRESENT_SHIFT);
+ cur = t;
+ }
+ uasm_i_andi(p, t, cur,
+ (_PAGE_PRESENT | _PAGE_WRITE) >> _PAGE_PRESENT_SHIFT);
+ uasm_i_xori(p, t, t,
+ (_PAGE_PRESENT | _PAGE_WRITE) >> _PAGE_PRESENT_SHIFT);
+ uasm_il_bnez(p, r, t, lid);
+ if (pte == t)
+ /* You lose the SMP race :-(*/
+ iPTE_LW(p, pte, ptr);
+ else
+ uasm_i_nop(p);
+}
+
+/* Make PTE writable, update software status bits as well, then store
+ * at PTR.
+ */
+static void
+build_make_write(u32 **p, struct uasm_reloc **r, unsigned int pte,
+ unsigned int ptr, unsigned int scratch)
+{
+ unsigned int mode = (_PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID
+ | _PAGE_DIRTY);
+
+ iPTE_SW(p, r, pte, ptr, mode, scratch);
+}
+
+/*
+ * Check if PTE can be modified, if not branch to LABEL. Regardless
+ * restore PTE with value from PTR when done.
+ */
+static void
+build_pte_modifiable(u32 **p, struct uasm_reloc **r,
+ unsigned int pte, unsigned int ptr, int scratch,
+ enum label_id lid)
+{
+ if (use_bbit_insns()) {
+ uasm_il_bbit0(p, r, pte, ilog2(_PAGE_WRITE), lid);
+ uasm_i_nop(p);
+ } else {
+ int t = scratch >= 0 ? scratch : pte;
+ uasm_i_srl(p, t, pte, _PAGE_WRITE_SHIFT);
+ uasm_i_andi(p, t, t, 1);
+ uasm_il_beqz(p, r, t, lid);
+ if (pte == t)
+ /* You lose the SMP race :-(*/
+ iPTE_LW(p, pte, ptr);
+ }
+}
+
+#ifndef CONFIG_MIPS_PGD_C0_CONTEXT
+
+
+/*
+ * R3000 style TLB load/store/modify handlers.
+ */
+
+/*
+ * This places the pte into ENTRYLO0 and writes it with tlbwi.
+ * Then it returns.
+ */
+static void
+build_r3000_pte_reload_tlbwi(u32 **p, unsigned int pte, unsigned int tmp)
+{
+ uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
+ uasm_i_mfc0(p, tmp, C0_EPC); /* cp0 delay */
+ uasm_i_tlbwi(p);
+ uasm_i_jr(p, tmp);
+ uasm_i_rfe(p); /* branch delay */
+}
+
+/*
+ * This places the pte into ENTRYLO0 and writes it with tlbwi
+ * or tlbwr as appropriate. This is because the index register
+ * may have the probe fail bit set as a result of a trap on a
+ * kseg2 access, i.e. without refill. Then it returns.
+ */
+static void
+build_r3000_tlb_reload_write(u32 **p, struct uasm_label **l,
+ struct uasm_reloc **r, unsigned int pte,
+ unsigned int tmp)
+{
+ uasm_i_mfc0(p, tmp, C0_INDEX);
+ uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
+ uasm_il_bltz(p, r, tmp, label_r3000_write_probe_fail); /* cp0 delay */
+ uasm_i_mfc0(p, tmp, C0_EPC); /* branch delay */
+ uasm_i_tlbwi(p); /* cp0 delay */
+ uasm_i_jr(p, tmp);
+ uasm_i_rfe(p); /* branch delay */
+ uasm_l_r3000_write_probe_fail(l, *p);
+ uasm_i_tlbwr(p); /* cp0 delay */
+ uasm_i_jr(p, tmp);
+ uasm_i_rfe(p); /* branch delay */
+}
+
+static void
+build_r3000_tlbchange_handler_head(u32 **p, unsigned int pte,
+ unsigned int ptr)
+{
+ long pgdc = (long)pgd_current;
+
+ uasm_i_mfc0(p, pte, C0_BADVADDR);
+ uasm_i_lui(p, ptr, uasm_rel_hi(pgdc)); /* cp0 delay */
+ uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
+ uasm_i_srl(p, pte, pte, 22); /* load delay */
+ uasm_i_sll(p, pte, pte, 2);
+ uasm_i_addu(p, ptr, ptr, pte);
+ uasm_i_mfc0(p, pte, C0_CONTEXT);
+ uasm_i_lw(p, ptr, 0, ptr); /* cp0 delay */
+ uasm_i_andi(p, pte, pte, 0xffc); /* load delay */
+ uasm_i_addu(p, ptr, ptr, pte);
+ uasm_i_lw(p, pte, 0, ptr);
+ uasm_i_tlbp(p); /* load delay */
+}
+
+static void build_r3000_tlb_load_handler(void)
+{
+ u32 *p = (u32 *)handle_tlbl;
+ struct uasm_label *l = labels;
+ struct uasm_reloc *r = relocs;
+
+ memset(p, 0, handle_tlbl_end - (char *)p);
+ memset(labels, 0, sizeof(labels));
+ memset(relocs, 0, sizeof(relocs));
+
+ build_r3000_tlbchange_handler_head(&p, K0, K1);
+ build_pte_present(&p, &r, K0, K1, -1, label_nopage_tlbl);
+ uasm_i_nop(&p); /* load delay */
+ build_make_valid(&p, &r, K0, K1, -1);
+ build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
+
+ uasm_l_nopage_tlbl(&l, p);
+ uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
+ uasm_i_nop(&p);
+
+ if (p >= (u32 *)handle_tlbl_end)
+ panic("TLB load handler fastpath space exceeded");
+
+ uasm_resolve_relocs(relocs, labels);
+ pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
+ (unsigned int)(p - (u32 *)handle_tlbl));
+
+ dump_handler("r3000_tlb_load", handle_tlbl, handle_tlbl_end);
+}
+
+static void build_r3000_tlb_store_handler(void)
+{
+ u32 *p = (u32 *)handle_tlbs;
+ struct uasm_label *l = labels;
+ struct uasm_reloc *r = relocs;
+
+ memset(p, 0, handle_tlbs_end - (char *)p);
+ memset(labels, 0, sizeof(labels));
+ memset(relocs, 0, sizeof(relocs));
+
+ build_r3000_tlbchange_handler_head(&p, K0, K1);
+ build_pte_writable(&p, &r, K0, K1, -1, label_nopage_tlbs);
+ uasm_i_nop(&p); /* load delay */
+ build_make_write(&p, &r, K0, K1, -1);
+ build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
+
+ uasm_l_nopage_tlbs(&l, p);
+ uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
+ uasm_i_nop(&p);
+
+ if (p >= (u32 *)handle_tlbs_end)
+ panic("TLB store handler fastpath space exceeded");
+
+ uasm_resolve_relocs(relocs, labels);
+ pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
+ (unsigned int)(p - (u32 *)handle_tlbs));
+
+ dump_handler("r3000_tlb_store", handle_tlbs, handle_tlbs_end);
+}
+
+static void build_r3000_tlb_modify_handler(void)
+{
+ u32 *p = (u32 *)handle_tlbm;
+ struct uasm_label *l = labels;
+ struct uasm_reloc *r = relocs;
+
+ memset(p, 0, handle_tlbm_end - (char *)p);
+ memset(labels, 0, sizeof(labels));
+ memset(relocs, 0, sizeof(relocs));
+
+ build_r3000_tlbchange_handler_head(&p, K0, K1);
+ build_pte_modifiable(&p, &r, K0, K1, -1, label_nopage_tlbm);
+ uasm_i_nop(&p); /* load delay */
+ build_make_write(&p, &r, K0, K1, -1);
+ build_r3000_pte_reload_tlbwi(&p, K0, K1);
+
+ uasm_l_nopage_tlbm(&l, p);
+ uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
+ uasm_i_nop(&p);
+
+ if (p >= (u32 *)handle_tlbm_end)
+ panic("TLB modify handler fastpath space exceeded");
+
+ uasm_resolve_relocs(relocs, labels);
+ pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
+ (unsigned int)(p - (u32 *)handle_tlbm));
+
+ dump_handler("r3000_tlb_modify", handle_tlbm, handle_tlbm_end);
+}
+#endif /* CONFIG_MIPS_PGD_C0_CONTEXT */
+
+static bool cpu_has_tlbex_tlbp_race(void)
+{
+ /*
+ * When a Hardware Table Walker is running it can replace TLB entries
+ * at any time, leading to a race between it & the CPU.
+ */
+ if (cpu_has_htw)
+ return true;
+
+ /*
+ * If the CPU shares FTLB RAM with its siblings then our entry may be
+ * replaced at any time by a sibling performing a write to the FTLB.
+ */
+ if (cpu_has_shared_ftlb_ram)
+ return true;
+
+ /* In all other cases there ought to be no race condition to handle */
+ return false;
+}
+
+/*
+ * R4000 style TLB load/store/modify handlers.
+ */
+static struct work_registers
+build_r4000_tlbchange_handler_head(u32 **p, struct uasm_label **l,
+ struct uasm_reloc **r)
+{
+ struct work_registers wr = build_get_work_registers(p);
+
+#ifdef CONFIG_64BIT
+ build_get_pmde64(p, l, r, wr.r1, wr.r2); /* get pmd in ptr */
+#else
+ build_get_pgde32(p, wr.r1, wr.r2); /* get pgd in ptr */
+#endif
+
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ /*
+ * For huge tlb entries, pmd doesn't contain an address but
+ * instead contains the tlb pte. Check the PAGE_HUGE bit and
+ * see if we need to jump to huge tlb processing.
+ */
+ build_is_huge_pte(p, r, wr.r1, wr.r2, label_tlb_huge_update);
+#endif
+
+ UASM_i_MFC0(p, wr.r1, C0_BADVADDR);
+ UASM_i_LW(p, wr.r2, 0, wr.r2);
+ UASM_i_SRL(p, wr.r1, wr.r1, PAGE_SHIFT - PTE_T_LOG2);
+ uasm_i_andi(p, wr.r1, wr.r1, (PTRS_PER_PTE - 1) << PTE_T_LOG2);
+ UASM_i_ADDU(p, wr.r2, wr.r2, wr.r1);
+
+#ifdef CONFIG_SMP
+ uasm_l_smp_pgtable_change(l, *p);
+#endif
+ iPTE_LW(p, wr.r1, wr.r2); /* get even pte */
+ if (!m4kc_tlbp_war()) {
+ build_tlb_probe_entry(p);
+ if (cpu_has_tlbex_tlbp_race()) {
+ /* race condition happens, leaving */
+ uasm_i_ehb(p);
+ uasm_i_mfc0(p, wr.r3, C0_INDEX);
+ uasm_il_bltz(p, r, wr.r3, label_leave);
+ uasm_i_nop(p);
+ }
+ }
+ return wr;
+}
+
+static void
+build_r4000_tlbchange_handler_tail(u32 **p, struct uasm_label **l,
+ struct uasm_reloc **r, unsigned int tmp,
+ unsigned int ptr)
+{
+ uasm_i_ori(p, ptr, ptr, sizeof(pte_t));
+ uasm_i_xori(p, ptr, ptr, sizeof(pte_t));
+ build_update_entries(p, tmp, ptr);
+ build_tlb_write_entry(p, l, r, tlb_indexed);
+ uasm_l_leave(l, *p);
+ build_restore_work_registers(p);
+ uasm_i_eret(p); /* return from trap */
+
+#ifdef CONFIG_64BIT
+ build_get_pgd_vmalloc64(p, l, r, tmp, ptr, not_refill);
+#endif
+}
+
+static void build_r4000_tlb_load_handler(void)
+{
+ u32 *p = (u32 *)msk_isa16_mode((ulong)handle_tlbl);
+ struct uasm_label *l = labels;
+ struct uasm_reloc *r = relocs;
+ struct work_registers wr;
+
+ memset(p, 0, handle_tlbl_end - (char *)p);
+ memset(labels, 0, sizeof(labels));
+ memset(relocs, 0, sizeof(relocs));
+
+ if (bcm1250_m3_war()) {
+ unsigned int segbits = 44;
+
+ uasm_i_dmfc0(&p, K0, C0_BADVADDR);
+ uasm_i_dmfc0(&p, K1, C0_ENTRYHI);
+ uasm_i_xor(&p, K0, K0, K1);
+ uasm_i_dsrl_safe(&p, K1, K0, 62);
+ uasm_i_dsrl_safe(&p, K0, K0, 12 + 1);
+ uasm_i_dsll_safe(&p, K0, K0, 64 + 12 + 1 - segbits);
+ uasm_i_or(&p, K0, K0, K1);
+ uasm_il_bnez(&p, &r, K0, label_leave);
+ /* No need for uasm_i_nop */
+ }
+
+ wr = build_r4000_tlbchange_handler_head(&p, &l, &r);
+ build_pte_present(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbl);
+ if (m4kc_tlbp_war())
+ build_tlb_probe_entry(&p);
+
+ if (cpu_has_rixi && !cpu_has_rixiex) {
+ /*
+ * If the page is not _PAGE_VALID, RI or XI could not
+ * have triggered it. Skip the expensive test..
+ */
+ if (use_bbit_insns()) {
+ uasm_il_bbit0(&p, &r, wr.r1, ilog2(_PAGE_VALID),
+ label_tlbl_goaround1);
+ } else {
+ uasm_i_andi(&p, wr.r3, wr.r1, _PAGE_VALID);
+ uasm_il_beqz(&p, &r, wr.r3, label_tlbl_goaround1);
+ }
+ uasm_i_nop(&p);
+
+ /*
+ * Warn if something may race with us & replace the TLB entry
+ * before we read it here. Everything with such races should
+ * also have dedicated RiXi exception handlers, so this
+ * shouldn't be hit.
+ */
+ WARN(cpu_has_tlbex_tlbp_race(), "Unhandled race in RiXi path");
+
+ uasm_i_tlbr(&p);
+
+ if (cpu_has_mips_r2_exec_hazard)
+ uasm_i_ehb(&p);
+
+ /* Examine entrylo 0 or 1 based on ptr. */
+ if (use_bbit_insns()) {
+ uasm_i_bbit0(&p, wr.r2, ilog2(sizeof(pte_t)), 8);
+ } else {
+ uasm_i_andi(&p, wr.r3, wr.r2, sizeof(pte_t));
+ uasm_i_beqz(&p, wr.r3, 8);
+ }
+ /* load it in the delay slot*/
+ UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO0);
+ /* load it if ptr is odd */
+ UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO1);
+ /*
+ * If the entryLo (now in wr.r3) is valid (bit 1), RI or
+ * XI must have triggered it.
+ */
+ if (use_bbit_insns()) {
+ uasm_il_bbit1(&p, &r, wr.r3, 1, label_nopage_tlbl);
+ uasm_i_nop(&p);
+ uasm_l_tlbl_goaround1(&l, p);
+ } else {
+ uasm_i_andi(&p, wr.r3, wr.r3, 2);
+ uasm_il_bnez(&p, &r, wr.r3, label_nopage_tlbl);
+ uasm_i_nop(&p);
+ }
+ uasm_l_tlbl_goaround1(&l, p);
+ }
+ build_make_valid(&p, &r, wr.r1, wr.r2, wr.r3);
+ build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);
+
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ /*
+ * This is the entry point when build_r4000_tlbchange_handler_head
+ * spots a huge page.
+ */
+ uasm_l_tlb_huge_update(&l, p);
+ iPTE_LW(&p, wr.r1, wr.r2);
+ build_pte_present(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbl);
+ build_tlb_probe_entry(&p);
+
+ if (cpu_has_rixi && !cpu_has_rixiex) {
+ /*
+ * If the page is not _PAGE_VALID, RI or XI could not
+ * have triggered it. Skip the expensive test..
+ */
+ if (use_bbit_insns()) {
+ uasm_il_bbit0(&p, &r, wr.r1, ilog2(_PAGE_VALID),
+ label_tlbl_goaround2);
+ } else {
+ uasm_i_andi(&p, wr.r3, wr.r1, _PAGE_VALID);
+ uasm_il_beqz(&p, &r, wr.r3, label_tlbl_goaround2);
+ }
+ uasm_i_nop(&p);
+
+ /*
+ * Warn if something may race with us & replace the TLB entry
+ * before we read it here. Everything with such races should
+ * also have dedicated RiXi exception handlers, so this
+ * shouldn't be hit.
+ */
+ WARN(cpu_has_tlbex_tlbp_race(), "Unhandled race in RiXi path");
+
+ uasm_i_tlbr(&p);
+
+ if (cpu_has_mips_r2_exec_hazard)
+ uasm_i_ehb(&p);
+
+ /* Examine entrylo 0 or 1 based on ptr. */
+ if (use_bbit_insns()) {
+ uasm_i_bbit0(&p, wr.r2, ilog2(sizeof(pte_t)), 8);
+ } else {
+ uasm_i_andi(&p, wr.r3, wr.r2, sizeof(pte_t));
+ uasm_i_beqz(&p, wr.r3, 8);
+ }
+ /* load it in the delay slot*/
+ UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO0);
+ /* load it if ptr is odd */
+ UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO1);
+ /*
+ * If the entryLo (now in wr.r3) is valid (bit 1), RI or
+ * XI must have triggered it.
+ */
+ if (use_bbit_insns()) {
+ uasm_il_bbit0(&p, &r, wr.r3, 1, label_tlbl_goaround2);
+ } else {
+ uasm_i_andi(&p, wr.r3, wr.r3, 2);
+ uasm_il_beqz(&p, &r, wr.r3, label_tlbl_goaround2);
+ }
+ if (PM_DEFAULT_MASK == 0)
+ uasm_i_nop(&p);
+ /*
+ * We clobbered C0_PAGEMASK, restore it. On the other branch
+ * it is restored in build_huge_tlb_write_entry.
+ */
+ build_restore_pagemask(&p, &r, wr.r3, label_nopage_tlbl, 0);
+
+ uasm_l_tlbl_goaround2(&l, p);
+ }
+ uasm_i_ori(&p, wr.r1, wr.r1, (_PAGE_ACCESSED | _PAGE_VALID));
+ build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2, 1);
+#endif
+
+ uasm_l_nopage_tlbl(&l, p);
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(&p, 0);
+ build_restore_work_registers(&p);
+#ifdef CONFIG_CPU_MICROMIPS
+ if ((unsigned long)tlb_do_page_fault_0 & 1) {
+ uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_0));
+ uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_0));
+ uasm_i_jr(&p, K0);
+ } else
+#endif
+ uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
+ uasm_i_nop(&p);
+
+ if (p >= (u32 *)handle_tlbl_end)
+ panic("TLB load handler fastpath space exceeded");
+
+ uasm_resolve_relocs(relocs, labels);
+ pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
+ (unsigned int)(p - (u32 *)handle_tlbl));
+
+ dump_handler("r4000_tlb_load", handle_tlbl, handle_tlbl_end);
+}
+
+static void build_r4000_tlb_store_handler(void)
+{
+ u32 *p = (u32 *)msk_isa16_mode((ulong)handle_tlbs);
+ struct uasm_label *l = labels;
+ struct uasm_reloc *r = relocs;
+ struct work_registers wr;
+
+ memset(p, 0, handle_tlbs_end - (char *)p);
+ memset(labels, 0, sizeof(labels));
+ memset(relocs, 0, sizeof(relocs));
+
+ wr = build_r4000_tlbchange_handler_head(&p, &l, &r);
+ build_pte_writable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbs);
+ if (m4kc_tlbp_war())
+ build_tlb_probe_entry(&p);
+ build_make_write(&p, &r, wr.r1, wr.r2, wr.r3);
+ build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);
+
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ /*
+ * This is the entry point when
+ * build_r4000_tlbchange_handler_head spots a huge page.
+ */
+ uasm_l_tlb_huge_update(&l, p);
+ iPTE_LW(&p, wr.r1, wr.r2);
+ build_pte_writable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbs);
+ build_tlb_probe_entry(&p);
+ uasm_i_ori(&p, wr.r1, wr.r1,
+ _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY);
+ build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2, 1);
+#endif
+
+ uasm_l_nopage_tlbs(&l, p);
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(&p, 0);
+ build_restore_work_registers(&p);
+#ifdef CONFIG_CPU_MICROMIPS
+ if ((unsigned long)tlb_do_page_fault_1 & 1) {
+ uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_1));
+ uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_1));
+ uasm_i_jr(&p, K0);
+ } else
+#endif
+ uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
+ uasm_i_nop(&p);
+
+ if (p >= (u32 *)handle_tlbs_end)
+ panic("TLB store handler fastpath space exceeded");
+
+ uasm_resolve_relocs(relocs, labels);
+ pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
+ (unsigned int)(p - (u32 *)handle_tlbs));
+
+ dump_handler("r4000_tlb_store", handle_tlbs, handle_tlbs_end);
+}
+
+static void build_r4000_tlb_modify_handler(void)
+{
+ u32 *p = (u32 *)msk_isa16_mode((ulong)handle_tlbm);
+ struct uasm_label *l = labels;
+ struct uasm_reloc *r = relocs;
+ struct work_registers wr;
+
+ memset(p, 0, handle_tlbm_end - (char *)p);
+ memset(labels, 0, sizeof(labels));
+ memset(relocs, 0, sizeof(relocs));
+
+ wr = build_r4000_tlbchange_handler_head(&p, &l, &r);
+ build_pte_modifiable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbm);
+ if (m4kc_tlbp_war())
+ build_tlb_probe_entry(&p);
+ /* Present and writable bits set, set accessed and dirty bits. */
+ build_make_write(&p, &r, wr.r1, wr.r2, wr.r3);
+ build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);
+
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ /*
+ * This is the entry point when
+ * build_r4000_tlbchange_handler_head spots a huge page.
+ */
+ uasm_l_tlb_huge_update(&l, p);
+ iPTE_LW(&p, wr.r1, wr.r2);
+ build_pte_modifiable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbm);
+ build_tlb_probe_entry(&p);
+ uasm_i_ori(&p, wr.r1, wr.r1,
+ _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY);
+ build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2, 0);
+#endif
+
+ uasm_l_nopage_tlbm(&l, p);
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(&p, 0);
+ build_restore_work_registers(&p);
+#ifdef CONFIG_CPU_MICROMIPS
+ if ((unsigned long)tlb_do_page_fault_1 & 1) {
+ uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_1));
+ uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_1));
+ uasm_i_jr(&p, K0);
+ } else
+#endif
+ uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
+ uasm_i_nop(&p);
+
+ if (p >= (u32 *)handle_tlbm_end)
+ panic("TLB modify handler fastpath space exceeded");
+
+ uasm_resolve_relocs(relocs, labels);
+ pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
+ (unsigned int)(p - (u32 *)handle_tlbm));
+
+ dump_handler("r4000_tlb_modify", handle_tlbm, handle_tlbm_end);
+}
+
+static void flush_tlb_handlers(void)
+{
+ local_flush_icache_range((unsigned long)handle_tlbl,
+ (unsigned long)handle_tlbl_end);
+ local_flush_icache_range((unsigned long)handle_tlbs,
+ (unsigned long)handle_tlbs_end);
+ local_flush_icache_range((unsigned long)handle_tlbm,
+ (unsigned long)handle_tlbm_end);
+ local_flush_icache_range((unsigned long)tlbmiss_handler_setup_pgd,
+ (unsigned long)tlbmiss_handler_setup_pgd_end);
+}
+
+static void print_htw_config(void)
+{
+ unsigned long config;
+ unsigned int pwctl;
+ const int field = 2 * sizeof(unsigned long);
+
+ config = read_c0_pwfield();
+ pr_debug("PWField (0x%0*lx): GDI: 0x%02lx UDI: 0x%02lx MDI: 0x%02lx PTI: 0x%02lx PTEI: 0x%02lx\n",
+ field, config,
+ (config & MIPS_PWFIELD_GDI_MASK) >> MIPS_PWFIELD_GDI_SHIFT,
+ (config & MIPS_PWFIELD_UDI_MASK) >> MIPS_PWFIELD_UDI_SHIFT,
+ (config & MIPS_PWFIELD_MDI_MASK) >> MIPS_PWFIELD_MDI_SHIFT,
+ (config & MIPS_PWFIELD_PTI_MASK) >> MIPS_PWFIELD_PTI_SHIFT,
+ (config & MIPS_PWFIELD_PTEI_MASK) >> MIPS_PWFIELD_PTEI_SHIFT);
+
+ config = read_c0_pwsize();
+ pr_debug("PWSize (0x%0*lx): PS: 0x%lx GDW: 0x%02lx UDW: 0x%02lx MDW: 0x%02lx PTW: 0x%02lx PTEW: 0x%02lx\n",
+ field, config,
+ (config & MIPS_PWSIZE_PS_MASK) >> MIPS_PWSIZE_PS_SHIFT,
+ (config & MIPS_PWSIZE_GDW_MASK) >> MIPS_PWSIZE_GDW_SHIFT,
+ (config & MIPS_PWSIZE_UDW_MASK) >> MIPS_PWSIZE_UDW_SHIFT,
+ (config & MIPS_PWSIZE_MDW_MASK) >> MIPS_PWSIZE_MDW_SHIFT,
+ (config & MIPS_PWSIZE_PTW_MASK) >> MIPS_PWSIZE_PTW_SHIFT,
+ (config & MIPS_PWSIZE_PTEW_MASK) >> MIPS_PWSIZE_PTEW_SHIFT);
+
+ pwctl = read_c0_pwctl();
+ pr_debug("PWCtl (0x%x): PWEn: 0x%x XK: 0x%x XS: 0x%x XU: 0x%x DPH: 0x%x HugePg: 0x%x Psn: 0x%x\n",
+ pwctl,
+ (pwctl & MIPS_PWCTL_PWEN_MASK) >> MIPS_PWCTL_PWEN_SHIFT,
+ (pwctl & MIPS_PWCTL_XK_MASK) >> MIPS_PWCTL_XK_SHIFT,
+ (pwctl & MIPS_PWCTL_XS_MASK) >> MIPS_PWCTL_XS_SHIFT,
+ (pwctl & MIPS_PWCTL_XU_MASK) >> MIPS_PWCTL_XU_SHIFT,
+ (pwctl & MIPS_PWCTL_DPH_MASK) >> MIPS_PWCTL_DPH_SHIFT,
+ (pwctl & MIPS_PWCTL_HUGEPG_MASK) >> MIPS_PWCTL_HUGEPG_SHIFT,
+ (pwctl & MIPS_PWCTL_PSN_MASK) >> MIPS_PWCTL_PSN_SHIFT);
+}
+
+static void config_htw_params(void)
+{
+ unsigned long pwfield, pwsize, ptei;
+ unsigned int config;
+
+ /*
+ * We are using 2-level page tables, so we only need to
+ * setup GDW and PTW appropriately. UDW and MDW will remain 0.
+ * The default value of GDI/UDI/MDI/PTI is 0xc. It is illegal to
+ * write values less than 0xc in these fields because the entire
+ * write will be dropped. As a result of which, we must preserve
+ * the original reset values and overwrite only what we really want.
+ */
+
+ pwfield = read_c0_pwfield();
+ /* re-initialize the GDI field */
+ pwfield &= ~MIPS_PWFIELD_GDI_MASK;
+ pwfield |= PGDIR_SHIFT << MIPS_PWFIELD_GDI_SHIFT;
+ /* re-initialize the PTI field including the even/odd bit */
+ pwfield &= ~MIPS_PWFIELD_PTI_MASK;
+ pwfield |= PAGE_SHIFT << MIPS_PWFIELD_PTI_SHIFT;
+ if (CONFIG_PGTABLE_LEVELS >= 3) {
+ pwfield &= ~MIPS_PWFIELD_MDI_MASK;
+ pwfield |= PMD_SHIFT << MIPS_PWFIELD_MDI_SHIFT;
+ }
+ /* Set the PTEI right shift */
+ ptei = _PAGE_GLOBAL_SHIFT << MIPS_PWFIELD_PTEI_SHIFT;
+ pwfield |= ptei;
+ write_c0_pwfield(pwfield);
+ /* Check whether the PTEI value is supported */
+ back_to_back_c0_hazard();
+ pwfield = read_c0_pwfield();
+ if (((pwfield & MIPS_PWFIELD_PTEI_MASK) << MIPS_PWFIELD_PTEI_SHIFT)
+ != ptei) {
+ pr_warn("Unsupported PTEI field value: 0x%lx. HTW will not be enabled",
+ ptei);
+ /*
+ * Drop option to avoid HTW being enabled via another path
+ * (eg htw_reset())
+ */
+ current_cpu_data.options &= ~MIPS_CPU_HTW;
+ return;
+ }
+
+ pwsize = ilog2(PTRS_PER_PGD) << MIPS_PWSIZE_GDW_SHIFT;
+ pwsize |= ilog2(PTRS_PER_PTE) << MIPS_PWSIZE_PTW_SHIFT;
+ if (CONFIG_PGTABLE_LEVELS >= 3)
+ pwsize |= ilog2(PTRS_PER_PMD) << MIPS_PWSIZE_MDW_SHIFT;
+
+ /* Set pointer size to size of directory pointers */
+ if (IS_ENABLED(CONFIG_64BIT))
+ pwsize |= MIPS_PWSIZE_PS_MASK;
+ /* PTEs may be multiple pointers long (e.g. with XPA) */
+ pwsize |= ((PTE_T_LOG2 - PGD_T_LOG2) << MIPS_PWSIZE_PTEW_SHIFT)
+ & MIPS_PWSIZE_PTEW_MASK;
+
+ write_c0_pwsize(pwsize);
+
+ /* Make sure everything is set before we enable the HTW */
+ back_to_back_c0_hazard();
+
+ /*
+ * Enable HTW (and only for XUSeg on 64-bit), and disable the rest of
+ * the pwctl fields.
+ */
+ config = 1 << MIPS_PWCTL_PWEN_SHIFT;
+ if (IS_ENABLED(CONFIG_64BIT))
+ config |= MIPS_PWCTL_XU_MASK;
+ write_c0_pwctl(config);
+ pr_info("Hardware Page Table Walker enabled\n");
+
+ print_htw_config();
+}
+
+static void config_xpa_params(void)
+{
+#ifdef CONFIG_XPA
+ unsigned int pagegrain;
+
+ if (mips_xpa_disabled) {
+ pr_info("Extended Physical Addressing (XPA) disabled\n");
+ return;
+ }
+
+ pagegrain = read_c0_pagegrain();
+ write_c0_pagegrain(pagegrain | PG_ELPA);
+ back_to_back_c0_hazard();
+ pagegrain = read_c0_pagegrain();
+
+ if (pagegrain & PG_ELPA)
+ pr_info("Extended Physical Addressing (XPA) enabled\n");
+ else
+ panic("Extended Physical Addressing (XPA) disabled");
+#endif
+}
+
+static void check_pabits(void)
+{
+ unsigned long entry;
+ unsigned pabits, fillbits;
+
+ if (!cpu_has_rixi || _PAGE_NO_EXEC == 0) {
+ /*
+ * We'll only be making use of the fact that we can rotate bits
+ * into the fill if the CPU supports RIXI, so don't bother
+ * probing this for CPUs which don't.
+ */
+ return;
+ }
+
+ write_c0_entrylo0(~0ul);
+ back_to_back_c0_hazard();
+ entry = read_c0_entrylo0();
+
+ /* clear all non-PFN bits */
+ entry &= ~((1 << MIPS_ENTRYLO_PFN_SHIFT) - 1);
+ entry &= ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
+
+ /* find a lower bound on PABITS, and upper bound on fill bits */
+ pabits = fls_long(entry) + 6;
+ fillbits = max_t(int, (int)BITS_PER_LONG - pabits, 0);
+
+ /* minus the RI & XI bits */
+ fillbits -= min_t(unsigned, fillbits, 2);
+
+ if (fillbits >= ilog2(_PAGE_NO_EXEC))
+ fill_includes_sw_bits = true;
+
+ pr_debug("Entry* registers contain %u fill bits\n", fillbits);
+}
+
+void build_tlb_refill_handler(void)
+{
+ /*
+ * The refill handler is generated per-CPU, multi-node systems
+ * may have local storage for it. The other handlers are only
+ * needed once.
+ */
+ static int run_once = 0;
+
+ if (IS_ENABLED(CONFIG_XPA) && !cpu_has_rixi)
+ panic("Kernels supporting XPA currently require CPUs with RIXI");
+
+ output_pgtable_bits_defines();
+ check_pabits();
+
+#ifdef CONFIG_64BIT
+ check_for_high_segbits = current_cpu_data.vmbits > (PGDIR_SHIFT + PGD_TABLE_ORDER + PAGE_SHIFT - 3);
+#endif
+
+ if (cpu_has_3kex) {
+#ifndef CONFIG_MIPS_PGD_C0_CONTEXT
+ if (!run_once) {
+ build_setup_pgd();
+ build_r3000_tlb_refill_handler();
+ build_r3000_tlb_load_handler();
+ build_r3000_tlb_store_handler();
+ build_r3000_tlb_modify_handler();
+ flush_tlb_handlers();
+ run_once++;
+ }
+#else
+ panic("No R3000 TLB refill handler");
+#endif
+ return;
+ }
+
+ if (cpu_has_ldpte)
+ setup_pw();
+
+ if (!run_once) {
+ scratch_reg = allocate_kscratch();
+ build_setup_pgd();
+ build_r4000_tlb_load_handler();
+ build_r4000_tlb_store_handler();
+ build_r4000_tlb_modify_handler();
+ if (cpu_has_ldpte)
+ build_loongson3_tlb_refill_handler();
+ else
+ build_r4000_tlb_refill_handler();
+ flush_tlb_handlers();
+ run_once++;
+ }
+ if (cpu_has_xpa)
+ config_xpa_params();
+ if (cpu_has_htw)
+ config_htw_params();
+}