summaryrefslogtreecommitdiffstats
path: root/arch/unicore32/mm
diff options
context:
space:
mode:
authorGuanXuetao <gxt@mprc.pku.edu.cn>2011-01-15 18:17:56 +0800
committerGuanXuetao <gxt@mprc.pku.edu.cn>2011-03-17 09:19:09 +0800
commit56372b0b2f533c9a25bd40a0577405f6ddb7cff2 (patch)
treec428578bf7392232e946756cfe12e9144122c212 /arch/unicore32/mm
parentb50f1704e9c441c58cf6dc05e72953ca30e1d4d2 (diff)
downloadlinux-56372b0b2f533c9a25bd40a0577405f6ddb7cff2.tar.gz
linux-56372b0b2f533c9a25bd40a0577405f6ddb7cff2.tar.bz2
linux-56372b0b2f533c9a25bd40a0577405f6ddb7cff2.zip
unicore32 core architecture: mm related: fault handling
This patch implements fault handling of memory management. Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/unicore32/mm')
-rw-r--r--arch/unicore32/mm/alignment.c523
-rw-r--r--arch/unicore32/mm/extable.c24
-rw-r--r--arch/unicore32/mm/fault.c479
-rw-r--r--arch/unicore32/mm/mmu.c533
-rw-r--r--arch/unicore32/mm/pgd.c102
5 files changed, 1661 insertions, 0 deletions
diff --git a/arch/unicore32/mm/alignment.c b/arch/unicore32/mm/alignment.c
new file mode 100644
index 000000000000..28f576d733ee
--- /dev/null
+++ b/arch/unicore32/mm/alignment.c
@@ -0,0 +1,523 @@
+/*
+ * linux/arch/unicore32/mm/alignment.c
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+/*
+ * TODO:
+ * FPU ldm/stm not handling
+ */
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+
+#include <asm/tlbflush.h>
+#include <asm/unaligned.h>
+
+#define CODING_BITS(i) (i & 0xe0000120)
+
+#define LDST_P_BIT(i) (i & (1 << 28)) /* Preindex */
+#define LDST_U_BIT(i) (i & (1 << 27)) /* Add offset */
+#define LDST_W_BIT(i) (i & (1 << 25)) /* Writeback */
+#define LDST_L_BIT(i) (i & (1 << 24)) /* Load */
+
+#define LDST_P_EQ_U(i) ((((i) ^ ((i) >> 1)) & (1 << 27)) == 0)
+
+#define LDSTH_I_BIT(i) (i & (1 << 26)) /* half-word immed */
+#define LDM_S_BIT(i) (i & (1 << 26)) /* write ASR from BSR */
+#define LDM_H_BIT(i) (i & (1 << 6)) /* select r0-r15 or r16-r31 */
+
+#define RN_BITS(i) ((i >> 19) & 31) /* Rn */
+#define RD_BITS(i) ((i >> 14) & 31) /* Rd */
+#define RM_BITS(i) (i & 31) /* Rm */
+
+#define REGMASK_BITS(i) (((i & 0x7fe00) >> 3) | (i & 0x3f))
+#define OFFSET_BITS(i) (i & 0x03fff)
+
+#define SHIFT_BITS(i) ((i >> 9) & 0x1f)
+#define SHIFT_TYPE(i) (i & 0xc0)
+#define SHIFT_LSL 0x00
+#define SHIFT_LSR 0x40
+#define SHIFT_ASR 0x80
+#define SHIFT_RORRRX 0xc0
+
+union offset_union {
+ unsigned long un;
+ signed long sn;
+};
+
+#define TYPE_ERROR 0
+#define TYPE_FAULT 1
+#define TYPE_LDST 2
+#define TYPE_DONE 3
+#define TYPE_SWAP 4
+#define TYPE_COLS 5 /* Coprocessor load/store */
+
+#define get8_unaligned_check(val, addr, err) \
+ __asm__( \
+ "1: ldb.u %1, [%2], #1\n" \
+ "2:\n" \
+ " .pushsection .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "3: mov %0, #1\n" \
+ " b 2b\n" \
+ " .popsection\n" \
+ " .pushsection __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 3b\n" \
+ " .popsection\n" \
+ : "=r" (err), "=&r" (val), "=r" (addr) \
+ : "0" (err), "2" (addr))
+
+#define get8t_unaligned_check(val, addr, err) \
+ __asm__( \
+ "1: ldb.u %1, [%2], #1\n" \
+ "2:\n" \
+ " .pushsection .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "3: mov %0, #1\n" \
+ " b 2b\n" \
+ " .popsection\n" \
+ " .pushsection __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 3b\n" \
+ " .popsection\n" \
+ : "=r" (err), "=&r" (val), "=r" (addr) \
+ : "0" (err), "2" (addr))
+
+#define get16_unaligned_check(val, addr) \
+ do { \
+ unsigned int err = 0, v, a = addr; \
+ get8_unaligned_check(val, a, err); \
+ get8_unaligned_check(v, a, err); \
+ val |= v << 8; \
+ if (err) \
+ goto fault; \
+ } while (0)
+
+#define put16_unaligned_check(val, addr) \
+ do { \
+ unsigned int err = 0, v = val, a = addr; \
+ __asm__( \
+ "1: stb.u %1, [%2], #1\n" \
+ " mov %1, %1 >> #8\n" \
+ "2: stb.u %1, [%2]\n" \
+ "3:\n" \
+ " .pushsection .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "4: mov %0, #1\n" \
+ " b 3b\n" \
+ " .popsection\n" \
+ " .pushsection __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 4b\n" \
+ " .long 2b, 4b\n" \
+ " .popsection\n" \
+ : "=r" (err), "=&r" (v), "=&r" (a) \
+ : "0" (err), "1" (v), "2" (a)); \
+ if (err) \
+ goto fault; \
+ } while (0)
+
+#define __put32_unaligned_check(ins, val, addr) \
+ do { \
+ unsigned int err = 0, v = val, a = addr; \
+ __asm__( \
+ "1: "ins" %1, [%2], #1\n" \
+ " mov %1, %1 >> #8\n" \
+ "2: "ins" %1, [%2], #1\n" \
+ " mov %1, %1 >> #8\n" \
+ "3: "ins" %1, [%2], #1\n" \
+ " mov %1, %1 >> #8\n" \
+ "4: "ins" %1, [%2]\n" \
+ "5:\n" \
+ " .pushsection .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "6: mov %0, #1\n" \
+ " b 5b\n" \
+ " .popsection\n" \
+ " .pushsection __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 6b\n" \
+ " .long 2b, 6b\n" \
+ " .long 3b, 6b\n" \
+ " .long 4b, 6b\n" \
+ " .popsection\n" \
+ : "=r" (err), "=&r" (v), "=&r" (a) \
+ : "0" (err), "1" (v), "2" (a)); \
+ if (err) \
+ goto fault; \
+ } while (0)
+
+#define get32_unaligned_check(val, addr) \
+ do { \
+ unsigned int err = 0, v, a = addr; \
+ get8_unaligned_check(val, a, err); \
+ get8_unaligned_check(v, a, err); \
+ val |= v << 8; \
+ get8_unaligned_check(v, a, err); \
+ val |= v << 16; \
+ get8_unaligned_check(v, a, err); \
+ val |= v << 24; \
+ if (err) \
+ goto fault; \
+ } while (0)
+
+#define put32_unaligned_check(val, addr) \
+ __put32_unaligned_check("stb.u", val, addr)
+
+#define get32t_unaligned_check(val, addr) \
+ do { \
+ unsigned int err = 0, v, a = addr; \
+ get8t_unaligned_check(val, a, err); \
+ get8t_unaligned_check(v, a, err); \
+ val |= v << 8; \
+ get8t_unaligned_check(v, a, err); \
+ val |= v << 16; \
+ get8t_unaligned_check(v, a, err); \
+ val |= v << 24; \
+ if (err) \
+ goto fault; \
+ } while (0)
+
+#define put32t_unaligned_check(val, addr) \
+ __put32_unaligned_check("stb.u", val, addr)
+
+static void
+do_alignment_finish_ldst(unsigned long addr, unsigned long instr,
+ struct pt_regs *regs, union offset_union offset)
+{
+ if (!LDST_U_BIT(instr))
+ offset.un = -offset.un;
+
+ if (!LDST_P_BIT(instr))
+ addr += offset.un;
+
+ if (!LDST_P_BIT(instr) || LDST_W_BIT(instr))
+ regs->uregs[RN_BITS(instr)] = addr;
+}
+
+static int
+do_alignment_ldrhstrh(unsigned long addr, unsigned long instr,
+ struct pt_regs *regs)
+{
+ unsigned int rd = RD_BITS(instr);
+
+ /* old value 0x40002120, can't judge swap instr correctly */
+ if ((instr & 0x4b003fe0) == 0x40000120)
+ goto swp;
+
+ if (LDST_L_BIT(instr)) {
+ unsigned long val;
+ get16_unaligned_check(val, addr);
+
+ /* signed half-word? */
+ if (instr & 0x80)
+ val = (signed long)((signed short)val);
+
+ regs->uregs[rd] = val;
+ } else
+ put16_unaligned_check(regs->uregs[rd], addr);
+
+ return TYPE_LDST;
+
+swp:
+ /* only handle swap word
+ * for swap byte should not active this alignment exception */
+ get32_unaligned_check(regs->uregs[RD_BITS(instr)], addr);
+ put32_unaligned_check(regs->uregs[RM_BITS(instr)], addr);
+ return TYPE_SWAP;
+
+fault:
+ return TYPE_FAULT;
+}
+
+static int
+do_alignment_ldrstr(unsigned long addr, unsigned long instr,
+ struct pt_regs *regs)
+{
+ unsigned int rd = RD_BITS(instr);
+
+ if (!LDST_P_BIT(instr) && LDST_W_BIT(instr))
+ goto trans;
+
+ if (LDST_L_BIT(instr))
+ get32_unaligned_check(regs->uregs[rd], addr);
+ else
+ put32_unaligned_check(regs->uregs[rd], addr);
+ return TYPE_LDST;
+
+trans:
+ if (LDST_L_BIT(instr))
+ get32t_unaligned_check(regs->uregs[rd], addr);
+ else
+ put32t_unaligned_check(regs->uregs[rd], addr);
+ return TYPE_LDST;
+
+fault:
+ return TYPE_FAULT;
+}
+
+/*
+ * LDM/STM alignment handler.
+ *
+ * There are 4 variants of this instruction:
+ *
+ * B = rn pointer before instruction, A = rn pointer after instruction
+ * ------ increasing address ----->
+ * | | r0 | r1 | ... | rx | |
+ * PU = 01 B A
+ * PU = 11 B A
+ * PU = 00 A B
+ * PU = 10 A B
+ */
+static int
+do_alignment_ldmstm(unsigned long addr, unsigned long instr,
+ struct pt_regs *regs)
+{
+ unsigned int rd, rn, pc_correction, reg_correction, nr_regs, regbits;
+ unsigned long eaddr, newaddr;
+
+ if (LDM_S_BIT(instr))
+ goto bad;
+
+ pc_correction = 4; /* processor implementation defined */
+
+ /* count the number of registers in the mask to be transferred */
+ nr_regs = hweight16(REGMASK_BITS(instr)) * 4;
+
+ rn = RN_BITS(instr);
+ newaddr = eaddr = regs->uregs[rn];
+
+ if (!LDST_U_BIT(instr))
+ nr_regs = -nr_regs;
+ newaddr += nr_regs;
+ if (!LDST_U_BIT(instr))
+ eaddr = newaddr;
+
+ if (LDST_P_EQ_U(instr)) /* U = P */
+ eaddr += 4;
+
+ /*
+ * This is a "hint" - we already have eaddr worked out by the
+ * processor for us.
+ */
+ if (addr != eaddr) {
+ printk(KERN_ERR "LDMSTM: PC = %08lx, instr = %08lx, "
+ "addr = %08lx, eaddr = %08lx\n",
+ instruction_pointer(regs), instr, addr, eaddr);
+ show_regs(regs);
+ }
+
+ if (LDM_H_BIT(instr))
+ reg_correction = 0x10;
+ else
+ reg_correction = 0x00;
+
+ for (regbits = REGMASK_BITS(instr), rd = 0; regbits;
+ regbits >>= 1, rd += 1)
+ if (regbits & 1) {
+ if (LDST_L_BIT(instr))
+ get32_unaligned_check(regs->
+ uregs[rd + reg_correction], eaddr);
+ else
+ put32_unaligned_check(regs->
+ uregs[rd + reg_correction], eaddr);
+ eaddr += 4;
+ }
+
+ if (LDST_W_BIT(instr))
+ regs->uregs[rn] = newaddr;
+ return TYPE_DONE;
+
+fault:
+ regs->UCreg_pc -= pc_correction;
+ return TYPE_FAULT;
+
+bad:
+ printk(KERN_ERR "Alignment trap: not handling ldm with s-bit set\n");
+ return TYPE_ERROR;
+}
+
+static int
+do_alignment(unsigned long addr, unsigned int error_code, struct pt_regs *regs)
+{
+ union offset_union offset;
+ unsigned long instr, instrptr;
+ int (*handler) (unsigned long addr, unsigned long instr,
+ struct pt_regs *regs);
+ unsigned int type;
+
+ instrptr = instruction_pointer(regs);
+ if (instrptr >= PAGE_OFFSET)
+ instr = *(unsigned long *)instrptr;
+ else {
+ __asm__ __volatile__(
+ "ldw.u %0, [%1]\n"
+ : "=&r"(instr)
+ : "r"(instrptr));
+ }
+
+ regs->UCreg_pc += 4;
+
+ switch (CODING_BITS(instr)) {
+ case 0x40000120: /* ldrh or strh */
+ if (LDSTH_I_BIT(instr))
+ offset.un = (instr & 0x3e00) >> 4 | (instr & 31);
+ else
+ offset.un = regs->uregs[RM_BITS(instr)];
+ handler = do_alignment_ldrhstrh;
+ break;
+
+ case 0x60000000: /* ldr or str immediate */
+ case 0x60000100: /* ldr or str immediate */
+ case 0x60000020: /* ldr or str immediate */
+ case 0x60000120: /* ldr or str immediate */
+ offset.un = OFFSET_BITS(instr);
+ handler = do_alignment_ldrstr;
+ break;
+
+ case 0x40000000: /* ldr or str register */
+ offset.un = regs->uregs[RM_BITS(instr)];
+ {
+ unsigned int shiftval = SHIFT_BITS(instr);
+
+ switch (SHIFT_TYPE(instr)) {
+ case SHIFT_LSL:
+ offset.un <<= shiftval;
+ break;
+
+ case SHIFT_LSR:
+ offset.un >>= shiftval;
+ break;
+
+ case SHIFT_ASR:
+ offset.sn >>= shiftval;
+ break;
+
+ case SHIFT_RORRRX:
+ if (shiftval == 0) {
+ offset.un >>= 1;
+ if (regs->UCreg_asr & PSR_C_BIT)
+ offset.un |= 1 << 31;
+ } else
+ offset.un = offset.un >> shiftval |
+ offset.un << (32 - shiftval);
+ break;
+ }
+ }
+ handler = do_alignment_ldrstr;
+ break;
+
+ case 0x80000000: /* ldm or stm */
+ case 0x80000020: /* ldm or stm */
+ handler = do_alignment_ldmstm;
+ break;
+
+ default:
+ goto bad;
+ }
+
+ type = handler(addr, instr, regs);
+
+ if (type == TYPE_ERROR || type == TYPE_FAULT)
+ goto bad_or_fault;
+
+ if (type == TYPE_LDST)
+ do_alignment_finish_ldst(addr, instr, regs, offset);
+
+ return 0;
+
+bad_or_fault:
+ if (type == TYPE_ERROR)
+ goto bad;
+ regs->UCreg_pc -= 4;
+ /*
+ * We got a fault - fix it up, or die.
+ */
+ do_bad_area(addr, error_code, regs);
+ return 0;
+
+bad:
+ /*
+ * Oops, we didn't handle the instruction.
+ * However, we must handle fpu instr firstly.
+ */
+#ifdef CONFIG_UNICORE_FPU_F64
+ /* handle co.load/store */
+#define CODING_COLS 0xc0000000
+#define COLS_OFFSET_BITS(i) (i & 0x1FF)
+#define COLS_L_BITS(i) (i & (1<<24))
+#define COLS_FN_BITS(i) ((i>>14) & 31)
+ if ((instr & 0xe0000000) == CODING_COLS) {
+ unsigned int fn = COLS_FN_BITS(instr);
+ unsigned long val = 0;
+ if (COLS_L_BITS(instr)) {
+ get32t_unaligned_check(val, addr);
+ switch (fn) {
+#define ASM_MTF(n) case n: \
+ __asm__ __volatile__("MTF %0, F" __stringify(n) \
+ : : "r"(val)); \
+ break;
+ ASM_MTF(0); ASM_MTF(1); ASM_MTF(2); ASM_MTF(3);
+ ASM_MTF(4); ASM_MTF(5); ASM_MTF(6); ASM_MTF(7);
+ ASM_MTF(8); ASM_MTF(9); ASM_MTF(10); ASM_MTF(11);
+ ASM_MTF(12); ASM_MTF(13); ASM_MTF(14); ASM_MTF(15);
+ ASM_MTF(16); ASM_MTF(17); ASM_MTF(18); ASM_MTF(19);
+ ASM_MTF(20); ASM_MTF(21); ASM_MTF(22); ASM_MTF(23);
+ ASM_MTF(24); ASM_MTF(25); ASM_MTF(26); ASM_MTF(27);
+ ASM_MTF(28); ASM_MTF(29); ASM_MTF(30); ASM_MTF(31);
+#undef ASM_MTF
+ }
+ } else {
+ switch (fn) {
+#define ASM_MFF(n) case n: \
+ __asm__ __volatile__("MFF %0, F" __stringify(n) \
+ : : "r"(val)); \
+ break;
+ ASM_MFF(0); ASM_MFF(1); ASM_MFF(2); ASM_MFF(3);
+ ASM_MFF(4); ASM_MFF(5); ASM_MFF(6); ASM_MFF(7);
+ ASM_MFF(8); ASM_MFF(9); ASM_MFF(10); ASM_MFF(11);
+ ASM_MFF(12); ASM_MFF(13); ASM_MFF(14); ASM_MFF(15);
+ ASM_MFF(16); ASM_MFF(17); ASM_MFF(18); ASM_MFF(19);
+ ASM_MFF(20); ASM_MFF(21); ASM_MFF(22); ASM_MFF(23);
+ ASM_MFF(24); ASM_MFF(25); ASM_MFF(26); ASM_MFF(27);
+ ASM_MFF(28); ASM_MFF(29); ASM_MFF(30); ASM_MFF(31);
+#undef ASM_MFF
+ }
+ put32t_unaligned_check(val, addr);
+ }
+ return TYPE_COLS;
+ }
+fault:
+ return TYPE_FAULT;
+#endif
+ printk(KERN_ERR "Alignment trap: not handling instruction "
+ "%08lx at [<%08lx>]\n", instr, instrptr);
+ return 1;
+}
+
+/*
+ * This needs to be done after sysctl_init, otherwise sys/ will be
+ * overwritten. Actually, this shouldn't be in sys/ at all since
+ * it isn't a sysctl, and it doesn't contain sysctl information.
+ */
+static int __init alignment_init(void)
+{
+ hook_fault_code(1, do_alignment, SIGBUS, BUS_ADRALN,
+ "alignment exception");
+
+ return 0;
+}
+
+fs_initcall(alignment_init);
diff --git a/arch/unicore32/mm/extable.c b/arch/unicore32/mm/extable.c
new file mode 100644
index 000000000000..6564180eb285
--- /dev/null
+++ b/arch/unicore32/mm/extable.c
@@ -0,0 +1,24 @@
+/*
+ * linux/arch/unicore32/mm/extable.c
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/module.h>
+#include <linux/uaccess.h>
+
+int fixup_exception(struct pt_regs *regs)
+{
+ const struct exception_table_entry *fixup;
+
+ fixup = search_exception_tables(instruction_pointer(regs));
+ if (fixup)
+ regs->UCreg_pc = fixup->fixup;
+
+ return fixup != NULL;
+}
diff --git a/arch/unicore32/mm/fault.c b/arch/unicore32/mm/fault.c
new file mode 100644
index 000000000000..283aa4b50b7a
--- /dev/null
+++ b/arch/unicore32/mm/fault.c
@@ -0,0 +1,479 @@
+/*
+ * linux/arch/unicore32/mm/fault.c
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/module.h>
+#include <linux/signal.h>
+#include <linux/mm.h>
+#include <linux/hardirq.h>
+#include <linux/init.h>
+#include <linux/kprobes.h>
+#include <linux/uaccess.h>
+#include <linux/page-flags.h>
+#include <linux/sched.h>
+#include <linux/io.h>
+
+#include <asm/system.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+
+/*
+ * Fault status register encodings. We steal bit 31 for our own purposes.
+ */
+#define FSR_LNX_PF (1 << 31)
+
+static inline int fsr_fs(unsigned int fsr)
+{
+ /* xyabcde will be abcde+xy */
+ return (fsr & 31) + ((fsr & (3 << 5)) >> 5);
+}
+
+/*
+ * This is useful to dump out the page tables associated with
+ * 'addr' in mm 'mm'.
+ */
+void show_pte(struct mm_struct *mm, unsigned long addr)
+{
+ pgd_t *pgd;
+
+ if (!mm)
+ mm = &init_mm;
+
+ printk(KERN_ALERT "pgd = %p\n", mm->pgd);
+ pgd = pgd_offset(mm, addr);
+ printk(KERN_ALERT "[%08lx] *pgd=%08lx", addr, pgd_val(*pgd));
+
+ do {
+ pmd_t *pmd;
+ pte_t *pte;
+
+ if (pgd_none(*pgd))
+ break;
+
+ if (pgd_bad(*pgd)) {
+ printk("(bad)");
+ break;
+ }
+
+ pmd = pmd_offset((pud_t *) pgd, addr);
+ if (PTRS_PER_PMD != 1)
+ printk(", *pmd=%08lx", pmd_val(*pmd));
+
+ if (pmd_none(*pmd))
+ break;
+
+ if (pmd_bad(*pmd)) {
+ printk("(bad)");
+ break;
+ }
+
+ /* We must not map this if we have highmem enabled */
+ if (PageHighMem(pfn_to_page(pmd_val(*pmd) >> PAGE_SHIFT)))
+ break;
+
+ pte = pte_offset_map(pmd, addr);
+ printk(", *pte=%08lx", pte_val(*pte));
+ pte_unmap(pte);
+ } while (0);
+
+ printk("\n");
+}
+
+/*
+ * Oops. The kernel tried to access some page that wasn't present.
+ */
+static void __do_kernel_fault(struct mm_struct *mm, unsigned long addr,
+ unsigned int fsr, struct pt_regs *regs)
+{
+ /*
+ * Are we prepared to handle this kernel fault?
+ */
+ if (fixup_exception(regs))
+ return;
+
+ /*
+ * No handler, we'll have to terminate things with extreme prejudice.
+ */
+ bust_spinlocks(1);
+ printk(KERN_ALERT
+ "Unable to handle kernel %s at virtual address %08lx\n",
+ (addr < PAGE_SIZE) ? "NULL pointer dereference" :
+ "paging request", addr);
+
+ show_pte(mm, addr);
+ die("Oops", regs, fsr);
+ bust_spinlocks(0);
+ do_exit(SIGKILL);
+}
+
+/*
+ * Something tried to access memory that isn't in our memory map..
+ * User mode accesses just cause a SIGSEGV
+ */
+static void __do_user_fault(struct task_struct *tsk, unsigned long addr,
+ unsigned int fsr, unsigned int sig, int code,
+ struct pt_regs *regs)
+{
+ struct siginfo si;
+
+ tsk->thread.address = addr;
+ tsk->thread.error_code = fsr;
+ tsk->thread.trap_no = 14;
+ si.si_signo = sig;
+ si.si_errno = 0;
+ si.si_code = code;
+ si.si_addr = (void __user *)addr;
+ force_sig_info(sig, &si, tsk);
+}
+
+void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
+{
+ struct task_struct *tsk = current;
+ struct mm_struct *mm = tsk->active_mm;
+
+ /*
+ * If we are in kernel mode at this point, we
+ * have no context to handle this fault with.
+ */
+ if (user_mode(regs))
+ __do_user_fault(tsk, addr, fsr, SIGSEGV, SEGV_MAPERR, regs);
+ else
+ __do_kernel_fault(mm, addr, fsr, regs);
+}
+
+#define VM_FAULT_BADMAP 0x010000
+#define VM_FAULT_BADACCESS 0x020000
+
+/*
+ * Check that the permissions on the VMA allow for the fault which occurred.
+ * If we encountered a write fault, we must have write permission, otherwise
+ * we allow any permission.
+ */
+static inline bool access_error(unsigned int fsr, struct vm_area_struct *vma)
+{
+ unsigned int mask = VM_READ | VM_WRITE | VM_EXEC;
+
+ if (!(fsr ^ 0x12)) /* write? */
+ mask = VM_WRITE;
+ if (fsr & FSR_LNX_PF)
+ mask = VM_EXEC;
+
+ return vma->vm_flags & mask ? false : true;
+}
+
+static int __do_pf(struct mm_struct *mm, unsigned long addr, unsigned int fsr,
+ struct task_struct *tsk)
+{
+ struct vm_area_struct *vma;
+ int fault;
+
+ vma = find_vma(mm, addr);
+ fault = VM_FAULT_BADMAP;
+ if (unlikely(!vma))
+ goto out;
+ if (unlikely(vma->vm_start > addr))
+ goto check_stack;
+
+ /*
+ * Ok, we have a good vm_area for this
+ * memory access, so we can handle it.
+ */
+good_area:
+ if (access_error(fsr, vma)) {
+ fault = VM_FAULT_BADACCESS;
+ goto out;
+ }
+
+ /*
+ * If for any reason at all we couldn't handle the fault, make
+ * sure we exit gracefully rather than endlessly redo the fault.
+ */
+ fault = handle_mm_fault(mm, vma, addr & PAGE_MASK,
+ (!(fsr ^ 0x12)) ? FAULT_FLAG_WRITE : 0);
+ if (unlikely(fault & VM_FAULT_ERROR))
+ return fault;
+ if (fault & VM_FAULT_MAJOR)
+ tsk->maj_flt++;
+ else
+ tsk->min_flt++;
+ return fault;
+
+check_stack:
+ if (vma->vm_flags & VM_GROWSDOWN && !expand_stack(vma, addr))
+ goto good_area;
+out:
+ return fault;
+}
+
+static int do_pf(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
+{
+ struct task_struct *tsk;
+ struct mm_struct *mm;
+ int fault, sig, code;
+
+ tsk = current;
+ mm = tsk->mm;
+
+ /*
+ * If we're in an interrupt or have no user
+ * context, we must not take the fault..
+ */
+ if (in_atomic() || !mm)
+ goto no_context;
+
+ /*
+ * As per x86, we may deadlock here. However, since the kernel only
+ * validly references user space from well defined areas of the code,
+ * we can bug out early if this is from code which shouldn't.
+ */
+ if (!down_read_trylock(&mm->mmap_sem)) {
+ if (!user_mode(regs)
+ && !search_exception_tables(regs->UCreg_pc))
+ goto no_context;
+ down_read(&mm->mmap_sem);
+ } else {
+ /*
+ * The above down_read_trylock() might have succeeded in
+ * which case, we'll have missed the might_sleep() from
+ * down_read()
+ */
+ might_sleep();
+#ifdef CONFIG_DEBUG_VM
+ if (!user_mode(regs) &&
+ !search_exception_tables(regs->UCreg_pc))
+ goto no_context;
+#endif
+ }
+
+ fault = __do_pf(mm, addr, fsr, tsk);
+ up_read(&mm->mmap_sem);
+
+ /*
+ * Handle the "normal" case first - VM_FAULT_MAJOR / VM_FAULT_MINOR
+ */
+ if (likely(!(fault &
+ (VM_FAULT_ERROR | VM_FAULT_BADMAP | VM_FAULT_BADACCESS))))
+ return 0;
+
+ if (fault & VM_FAULT_OOM) {
+ /*
+ * We ran out of memory, call the OOM killer, and return to
+ * userspace (which will retry the fault, or kill us if we
+ * got oom-killed)
+ */
+ pagefault_out_of_memory();
+ return 0;
+ }
+
+ /*
+ * If we are in kernel mode at this point, we
+ * have no context to handle this fault with.
+ */
+ if (!user_mode(regs))
+ goto no_context;
+
+ if (fault & VM_FAULT_SIGBUS) {
+ /*
+ * We had some memory, but were unable to
+ * successfully fix up this page fault.
+ */
+ sig = SIGBUS;
+ code = BUS_ADRERR;
+ } else {
+ /*
+ * Something tried to access memory that
+ * isn't in our memory map..
+ */
+ sig = SIGSEGV;
+ code = fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR;
+ }
+
+ __do_user_fault(tsk, addr, fsr, sig, code, regs);
+ return 0;
+
+no_context:
+ __do_kernel_fault(mm, addr, fsr, regs);
+ return 0;
+}
+
+/*
+ * First Level Translation Fault Handler
+ *
+ * We enter here because the first level page table doesn't contain
+ * a valid entry for the address.
+ *
+ * If the address is in kernel space (>= TASK_SIZE), then we are
+ * probably faulting in the vmalloc() area.
+ *
+ * If the init_task's first level page tables contains the relevant
+ * entry, we copy the it to this task. If not, we send the process
+ * a signal, fixup the exception, or oops the kernel.
+ *
+ * NOTE! We MUST NOT take any locks for this case. We may be in an
+ * interrupt or a critical region, and should only copy the information
+ * from the master page table, nothing more.
+ */
+static int do_ifault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
+{
+ unsigned int index;
+ pgd_t *pgd, *pgd_k;
+ pmd_t *pmd, *pmd_k;
+
+ if (addr < TASK_SIZE)
+ return do_pf(addr, fsr, regs);
+
+ if (user_mode(regs))
+ goto bad_area;
+
+ index = pgd_index(addr);
+
+ pgd = cpu_get_pgd() + index;
+ pgd_k = init_mm.pgd + index;
+
+ if (pgd_none(*pgd_k))
+ goto bad_area;
+
+ pmd_k = pmd_offset((pud_t *) pgd_k, addr);
+ pmd = pmd_offset((pud_t *) pgd, addr);
+
+ if (pmd_none(*pmd_k))
+ goto bad_area;
+
+ set_pmd(pmd, *pmd_k);
+ flush_pmd_entry(pmd);
+ return 0;
+
+bad_area:
+ do_bad_area(addr, fsr, regs);
+ return 0;
+}
+
+/*
+ * This abort handler always returns "fault".
+ */
+static int do_bad(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
+{
+ return 1;
+}
+
+static int do_good(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
+{
+ unsigned int res1, res2;
+
+ printk("dabt exception but no error!\n");
+
+ __asm__ __volatile__(
+ "mff %0,f0\n"
+ "mff %1,f1\n"
+ : "=r"(res1), "=r"(res2)
+ :
+ : "memory");
+
+ printk(KERN_EMERG "r0 :%08x r1 :%08x\n", res1, res2);
+ panic("shut up\n");
+ return 0;
+}
+
+static struct fsr_info {
+ int (*fn) (unsigned long addr, unsigned int fsr, struct pt_regs *regs);
+ int sig;
+ int code;
+ const char *name;
+} fsr_info[] = {
+ /*
+ * The following are the standard Unicore-I and UniCore-II aborts.
+ */
+ { do_good, SIGBUS, 0, "no error" },
+ { do_bad, SIGBUS, BUS_ADRALN, "alignment exception" },
+ { do_bad, SIGBUS, BUS_OBJERR, "external exception" },
+ { do_bad, SIGBUS, 0, "burst operation" },
+ { do_bad, SIGBUS, 0, "unknown 00100" },
+ { do_ifault, SIGSEGV, SEGV_MAPERR, "2nd level pt non-exist"},
+ { do_bad, SIGBUS, 0, "2nd lvl large pt non-exist" },
+ { do_bad, SIGBUS, 0, "invalid pte" },
+ { do_pf, SIGSEGV, SEGV_MAPERR, "page miss" },
+ { do_bad, SIGBUS, 0, "middle page miss" },
+ { do_bad, SIGBUS, 0, "large page miss" },
+ { do_pf, SIGSEGV, SEGV_MAPERR, "super page (section) miss" },
+ { do_bad, SIGBUS, 0, "unknown 01100" },
+ { do_bad, SIGBUS, 0, "unknown 01101" },
+ { do_bad, SIGBUS, 0, "unknown 01110" },
+ { do_bad, SIGBUS, 0, "unknown 01111" },
+ { do_bad, SIGBUS, 0, "addr: up 3G or IO" },
+ { do_pf, SIGSEGV, SEGV_ACCERR, "read unreadable addr" },
+ { do_pf, SIGSEGV, SEGV_ACCERR, "write unwriteable addr"},
+ { do_pf, SIGSEGV, SEGV_ACCERR, "exec unexecutable addr"},
+ { do_bad, SIGBUS, 0, "unknown 10100" },
+ { do_bad, SIGBUS, 0, "unknown 10101" },
+ { do_bad, SIGBUS, 0, "unknown 10110" },
+ { do_bad, SIGBUS, 0, "unknown 10111" },
+ { do_bad, SIGBUS, 0, "unknown 11000" },
+ { do_bad, SIGBUS, 0, "unknown 11001" },
+ { do_bad, SIGBUS, 0, "unknown 11010" },
+ { do_bad, SIGBUS, 0, "unknown 11011" },
+ { do_bad, SIGBUS, 0, "unknown 11100" },
+ { do_bad, SIGBUS, 0, "unknown 11101" },
+ { do_bad, SIGBUS, 0, "unknown 11110" },
+ { do_bad, SIGBUS, 0, "unknown 11111" }
+};
+
+void __init hook_fault_code(int nr,
+ int (*fn) (unsigned long, unsigned int, struct pt_regs *),
+ int sig, int code, const char *name)
+{
+ if (nr < 0 || nr >= ARRAY_SIZE(fsr_info))
+ BUG();
+
+ fsr_info[nr].fn = fn;
+ fsr_info[nr].sig = sig;
+ fsr_info[nr].code = code;
+ fsr_info[nr].name = name;
+}
+
+/*
+ * Dispatch a data abort to the relevant handler.
+ */
+asmlinkage void do_DataAbort(unsigned long addr, unsigned int fsr,
+ struct pt_regs *regs)
+{
+ const struct fsr_info *inf = fsr_info + fsr_fs(fsr);
+ struct siginfo info;
+
+ if (!inf->fn(addr, fsr & ~FSR_LNX_PF, regs))
+ return;
+
+ printk(KERN_ALERT "Unhandled fault: %s (0x%03x) at 0x%08lx\n",
+ inf->name, fsr, addr);
+
+ info.si_signo = inf->sig;
+ info.si_errno = 0;
+ info.si_code = inf->code;
+ info.si_addr = (void __user *)addr;
+ uc32_notify_die("", regs, &info, fsr, 0);
+}
+
+asmlinkage void do_PrefetchAbort(unsigned long addr,
+ unsigned int ifsr, struct pt_regs *regs)
+{
+ const struct fsr_info *inf = fsr_info + fsr_fs(ifsr);
+ struct siginfo info;
+
+ if (!inf->fn(addr, ifsr | FSR_LNX_PF, regs))
+ return;
+
+ printk(KERN_ALERT "Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n",
+ inf->name, ifsr, addr);
+
+ info.si_signo = inf->sig;
+ info.si_errno = 0;
+ info.si_code = inf->code;
+ info.si_addr = (void __user *)addr;
+ uc32_notify_die("", regs, &info, ifsr, 0);
+}
diff --git a/arch/unicore32/mm/mmu.c b/arch/unicore32/mm/mmu.c
new file mode 100644
index 000000000000..7bf3d588631f
--- /dev/null
+++ b/arch/unicore32/mm/mmu.c
@@ -0,0 +1,533 @@
+/*
+ * linux/arch/unicore32/mm/mmu.c
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/mman.h>
+#include <linux/nodemask.h>
+#include <linux/memblock.h>
+#include <linux/fs.h>
+#include <linux/bootmem.h>
+#include <linux/io.h>
+
+#include <asm/cputype.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <asm/sizes.h>
+#include <asm/tlb.h>
+
+#include <mach/map.h>
+
+#include "mm.h"
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+
+/*
+ * empty_zero_page is a special page that is used for
+ * zero-initialized data and COW.
+ */
+struct page *empty_zero_page;
+EXPORT_SYMBOL(empty_zero_page);
+
+/*
+ * The pmd table for the upper-most set of pages.
+ */
+pmd_t *top_pmd;
+
+pgprot_t pgprot_user;
+EXPORT_SYMBOL(pgprot_user);
+
+pgprot_t pgprot_kernel;
+EXPORT_SYMBOL(pgprot_kernel);
+
+static int __init noalign_setup(char *__unused)
+{
+ cr_alignment &= ~CR_A;
+ cr_no_alignment &= ~CR_A;
+ set_cr(cr_alignment);
+ return 1;
+}
+__setup("noalign", noalign_setup);
+
+void adjust_cr(unsigned long mask, unsigned long set)
+{
+ unsigned long flags;
+
+ mask &= ~CR_A;
+
+ set &= mask;
+
+ local_irq_save(flags);
+
+ cr_no_alignment = (cr_no_alignment & ~mask) | set;
+ cr_alignment = (cr_alignment & ~mask) | set;
+
+ set_cr((get_cr() & ~mask) | set);
+
+ local_irq_restore(flags);
+}
+
+struct map_desc {
+ unsigned long virtual;
+ unsigned long pfn;
+ unsigned long length;
+ unsigned int type;
+};
+
+#define PROT_PTE_DEVICE (PTE_PRESENT | PTE_YOUNG | \
+ PTE_DIRTY | PTE_READ | PTE_WRITE)
+#define PROT_SECT_DEVICE (PMD_TYPE_SECT | PMD_PRESENT | \
+ PMD_SECT_READ | PMD_SECT_WRITE)
+
+static struct mem_type mem_types[] = {
+ [MT_DEVICE] = { /* Strongly ordered */
+ .prot_pte = PROT_PTE_DEVICE,
+ .prot_l1 = PMD_TYPE_TABLE | PMD_PRESENT,
+ .prot_sect = PROT_SECT_DEVICE,
+ },
+ /*
+ * MT_KUSER: pte for vecpage -- cacheable,
+ * and sect for unigfx mmap -- noncacheable
+ */
+ [MT_KUSER] = {
+ .prot_pte = PTE_PRESENT | PTE_YOUNG | PTE_DIRTY |
+ PTE_CACHEABLE | PTE_READ | PTE_EXEC,
+ .prot_l1 = PMD_TYPE_TABLE | PMD_PRESENT,
+ .prot_sect = PROT_SECT_DEVICE,
+ },
+ [MT_HIGH_VECTORS] = {
+ .prot_pte = PTE_PRESENT | PTE_YOUNG | PTE_DIRTY |
+ PTE_CACHEABLE | PTE_READ | PTE_WRITE |
+ PTE_EXEC,
+ .prot_l1 = PMD_TYPE_TABLE | PMD_PRESENT,
+ },
+ [MT_MEMORY] = {
+ .prot_pte = PTE_PRESENT | PTE_YOUNG | PTE_DIRTY |
+ PTE_WRITE | PTE_EXEC,
+ .prot_l1 = PMD_TYPE_TABLE | PMD_PRESENT,
+ .prot_sect = PMD_TYPE_SECT | PMD_PRESENT | PMD_SECT_CACHEABLE |
+ PMD_SECT_READ | PMD_SECT_WRITE | PMD_SECT_EXEC,
+ },
+ [MT_ROM] = {
+ .prot_sect = PMD_TYPE_SECT | PMD_PRESENT | PMD_SECT_CACHEABLE |
+ PMD_SECT_READ,
+ },
+};
+
+const struct mem_type *get_mem_type(unsigned int type)
+{
+ return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
+}
+EXPORT_SYMBOL(get_mem_type);
+
+/*
+ * Adjust the PMD section entries according to the CPU in use.
+ */
+static void __init build_mem_type_table(void)
+{
+ pgprot_user = __pgprot(PTE_PRESENT | PTE_YOUNG | PTE_CACHEABLE);
+ pgprot_kernel = __pgprot(PTE_PRESENT | PTE_YOUNG |
+ PTE_DIRTY | PTE_READ | PTE_WRITE |
+ PTE_EXEC | PTE_CACHEABLE);
+}
+
+#define vectors_base() (vectors_high() ? 0xffff0000 : 0)
+
+static void __init *early_alloc(unsigned long sz)
+{
+ void *ptr = __va(memblock_alloc(sz, sz));
+ memset(ptr, 0, sz);
+ return ptr;
+}
+
+static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr,
+ unsigned long prot)
+{
+ if (pmd_none(*pmd)) {
+ pte_t *pte = early_alloc(PTRS_PER_PTE * sizeof(pte_t));
+ __pmd_populate(pmd, __pa(pte) | prot);
+ }
+ BUG_ON(pmd_bad(*pmd));
+ return pte_offset_kernel(pmd, addr);
+}
+
+static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
+ unsigned long end, unsigned long pfn,
+ const struct mem_type *type)
+{
+ pte_t *pte = early_pte_alloc(pmd, addr, type->prot_l1);
+ do {
+ set_pte(pte, pfn_pte(pfn, __pgprot(type->prot_pte)));
+ pfn++;
+ } while (pte++, addr += PAGE_SIZE, addr != end);
+}
+
+static void __init alloc_init_section(pgd_t *pgd, unsigned long addr,
+ unsigned long end, unsigned long phys,
+ const struct mem_type *type)
+{
+ pmd_t *pmd = pmd_offset((pud_t *)pgd, addr);
+
+ /*
+ * Try a section mapping - end, addr and phys must all be aligned
+ * to a section boundary.
+ */
+ if (((addr | end | phys) & ~SECTION_MASK) == 0) {
+ pmd_t *p = pmd;
+
+ do {
+ set_pmd(pmd, __pmd(phys | type->prot_sect));
+ phys += SECTION_SIZE;
+ } while (pmd++, addr += SECTION_SIZE, addr != end);
+
+ flush_pmd_entry(p);
+ } else {
+ /*
+ * No need to loop; pte's aren't interested in the
+ * individual L1 entries.
+ */
+ alloc_init_pte(pmd, addr, end, __phys_to_pfn(phys), type);
+ }
+}
+
+/*
+ * Create the page directory entries and any necessary
+ * page tables for the mapping specified by `md'. We
+ * are able to cope here with varying sizes and address
+ * offsets, and we take full advantage of sections.
+ */
+static void __init create_mapping(struct map_desc *md)
+{
+ unsigned long phys, addr, length, end;
+ const struct mem_type *type;
+ pgd_t *pgd;
+
+ if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
+ printk(KERN_WARNING "BUG: not creating mapping for "
+ "0x%08llx at 0x%08lx in user region\n",
+ __pfn_to_phys((u64)md->pfn), md->virtual);
+ return;
+ }
+
+ if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
+ md->virtual >= PAGE_OFFSET && md->virtual < VMALLOC_END) {
+ printk(KERN_WARNING "BUG: mapping for 0x%08llx at 0x%08lx "
+ "overlaps vmalloc space\n",
+ __pfn_to_phys((u64)md->pfn), md->virtual);
+ }
+
+ type = &mem_types[md->type];
+
+ addr = md->virtual & PAGE_MASK;
+ phys = (unsigned long)__pfn_to_phys(md->pfn);
+ length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
+
+ if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
+ printk(KERN_WARNING "BUG: map for 0x%08lx at 0x%08lx can not "
+ "be mapped using pages, ignoring.\n",
+ __pfn_to_phys(md->pfn), addr);
+ return;
+ }
+
+ pgd = pgd_offset_k(addr);
+ end = addr + length;
+ do {
+ unsigned long next = pgd_addr_end(addr, end);
+
+ alloc_init_section(pgd, addr, next, phys, type);
+
+ phys += next - addr;
+ addr = next;
+ } while (pgd++, addr != end);
+}
+
+static void * __initdata vmalloc_min = (void *)(VMALLOC_END - SZ_128M);
+
+/*
+ * vmalloc=size forces the vmalloc area to be exactly 'size'
+ * bytes. This can be used to increase (or decrease) the vmalloc
+ * area - the default is 128m.
+ */
+static int __init early_vmalloc(char *arg)
+{
+ unsigned long vmalloc_reserve = memparse(arg, NULL);
+
+ if (vmalloc_reserve < SZ_16M) {
+ vmalloc_reserve = SZ_16M;
+ printk(KERN_WARNING
+ "vmalloc area too small, limiting to %luMB\n",
+ vmalloc_reserve >> 20);
+ }
+
+ if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
+ vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
+ printk(KERN_WARNING
+ "vmalloc area is too big, limiting to %luMB\n",
+ vmalloc_reserve >> 20);
+ }
+
+ vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve);
+ return 0;
+}
+early_param("vmalloc", early_vmalloc);
+
+static phys_addr_t lowmem_limit __initdata = SZ_1G;
+
+static void __init sanity_check_meminfo(void)
+{
+ int i, j;
+
+ lowmem_limit = __pa(vmalloc_min - 1) + 1;
+ memblock_set_current_limit(lowmem_limit);
+
+ for (i = 0, j = 0; i < meminfo.nr_banks; i++) {
+ struct membank *bank = &meminfo.bank[j];
+ *bank = meminfo.bank[i];
+ j++;
+ }
+ meminfo.nr_banks = j;
+}
+
+static inline void prepare_page_table(void)
+{
+ unsigned long addr;
+ phys_addr_t end;
+
+ /*
+ * Clear out all the mappings below the kernel image.
+ */
+ for (addr = 0; addr < MODULES_VADDR; addr += PGDIR_SIZE)
+ pmd_clear(pmd_off_k(addr));
+
+ for ( ; addr < PAGE_OFFSET; addr += PGDIR_SIZE)
+ pmd_clear(pmd_off_k(addr));
+
+ /*
+ * Find the end of the first block of lowmem.
+ */
+ end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
+ if (end >= lowmem_limit)
+ end = lowmem_limit;
+
+ /*
+ * Clear out all the kernel space mappings, except for the first
+ * memory bank, up to the end of the vmalloc region.
+ */
+ for (addr = __phys_to_virt(end);
+ addr < VMALLOC_END; addr += PGDIR_SIZE)
+ pmd_clear(pmd_off_k(addr));
+}
+
+/*
+ * Reserve the special regions of memory
+ */
+void __init uc32_mm_memblock_reserve(void)
+{
+ /*
+ * Reserve the page tables. These are already in use,
+ * and can only be in node 0.
+ */
+ memblock_reserve(__pa(swapper_pg_dir), PTRS_PER_PGD * sizeof(pgd_t));
+
+#ifdef CONFIG_PUV3_UNIGFX
+ /*
+ * These should likewise go elsewhere. They pre-reserve the
+ * screen/video memory region at the 48M~64M of main system memory.
+ */
+ memblock_reserve(PKUNITY_UNIGFX_MMAP_BASE, PKUNITY_UNIGFX_MMAP_SIZE);
+ memblock_reserve(PKUNITY_UVC_MMAP_BASE, PKUNITY_UVC_MMAP_SIZE);
+#endif
+}
+
+/*
+ * Set up device the mappings. Since we clear out the page tables for all
+ * mappings above VMALLOC_END, we will remove any debug device mappings.
+ * This means you have to be careful how you debug this function, or any
+ * called function. This means you can't use any function or debugging
+ * method which may touch any device, otherwise the kernel _will_ crash.
+ */
+static void __init devicemaps_init(void)
+{
+ struct map_desc map;
+ unsigned long addr;
+ void *vectors;
+
+ /*
+ * Allocate the vector page early.
+ */
+ vectors = early_alloc(PAGE_SIZE);
+
+ for (addr = VMALLOC_END; addr; addr += PGDIR_SIZE)
+ pmd_clear(pmd_off_k(addr));
+
+ /*
+ * Create a mapping for UniGFX VRAM
+ */
+#ifdef CONFIG_PUV3_UNIGFX
+ map.pfn = __phys_to_pfn(PKUNITY_UNIGFX_MMAP_BASE);
+ map.virtual = KUSER_UNIGFX_BASE;
+ map.length = PKUNITY_UNIGFX_MMAP_SIZE;
+ map.type = MT_KUSER;
+ create_mapping(&map);
+#endif
+
+ /*
+ * Create a mapping for the machine vectors at the high-vectors
+ * location (0xffff0000). If we aren't using high-vectors, also
+ * create a mapping at the low-vectors virtual address.
+ */
+ map.pfn = __phys_to_pfn(virt_to_phys(vectors));
+ map.virtual = VECTORS_BASE;
+ map.length = PAGE_SIZE;
+ map.type = MT_HIGH_VECTORS;
+ create_mapping(&map);
+
+ /*
+ * Create a mapping for the kuser page at the special
+ * location (0xbfff0000) to the same vectors location.
+ */
+ map.pfn = __phys_to_pfn(virt_to_phys(vectors));
+ map.virtual = KUSER_VECPAGE_BASE;
+ map.length = PAGE_SIZE;
+ map.type = MT_KUSER;
+ create_mapping(&map);
+
+ /*
+ * Finally flush the caches and tlb to ensure that we're in a
+ * consistent state wrt the writebuffer. This also ensures that
+ * any write-allocated cache lines in the vector page are written
+ * back. After this point, we can start to touch devices again.
+ */
+ local_flush_tlb_all();
+ flush_cache_all();
+}
+
+static void __init map_lowmem(void)
+{
+ struct memblock_region *reg;
+
+ /* Map all the lowmem memory banks. */
+ for_each_memblock(memory, reg) {
+ phys_addr_t start = reg->base;
+ phys_addr_t end = start + reg->size;
+ struct map_desc map;
+
+ if (end > lowmem_limit)
+ end = lowmem_limit;
+ if (start >= end)
+ break;
+
+ map.pfn = __phys_to_pfn(start);
+ map.virtual = __phys_to_virt(start);
+ map.length = end - start;
+ map.type = MT_MEMORY;
+
+ create_mapping(&map);
+ }
+}
+
+/*
+ * paging_init() sets up the page tables, initialises the zone memory
+ * maps, and sets up the zero page, bad page and bad page tables.
+ */
+void __init paging_init(void)
+{
+ void *zero_page;
+
+ build_mem_type_table();
+ sanity_check_meminfo();
+ prepare_page_table();
+ map_lowmem();
+ devicemaps_init();
+
+ top_pmd = pmd_off_k(0xffff0000);
+
+ /* allocate the zero page. */
+ zero_page = early_alloc(PAGE_SIZE);
+
+ bootmem_init();
+
+ empty_zero_page = virt_to_page(zero_page);
+ __flush_dcache_page(NULL, empty_zero_page);
+}
+
+/*
+ * In order to soft-boot, we need to insert a 1:1 mapping in place of
+ * the user-mode pages. This will then ensure that we have predictable
+ * results when turning the mmu off
+ */
+void setup_mm_for_reboot(char mode)
+{
+ unsigned long base_pmdval;
+ pgd_t *pgd;
+ int i;
+
+ /*
+ * We need to access to user-mode page tables here. For kernel threads
+ * we don't have any user-mode mappings so we use the context that we
+ * "borrowed".
+ */
+ pgd = current->active_mm->pgd;
+
+ base_pmdval = PMD_SECT_WRITE | PMD_SECT_READ | PMD_TYPE_SECT;
+
+ for (i = 0; i < FIRST_USER_PGD_NR + USER_PTRS_PER_PGD; i++, pgd++) {
+ unsigned long pmdval = (i << PGDIR_SHIFT) | base_pmdval;
+ pmd_t *pmd;
+
+ pmd = pmd_off(pgd, i << PGDIR_SHIFT);
+ set_pmd(pmd, __pmd(pmdval));
+ flush_pmd_entry(pmd);
+ }
+
+ local_flush_tlb_all();
+}
+
+/*
+ * Take care of architecture specific things when placing a new PTE into
+ * a page table, or changing an existing PTE. Basically, there are two
+ * things that we need to take care of:
+ *
+ * 1. If PG_dcache_clean is not set for the page, we need to ensure
+ * that any cache entries for the kernels virtual memory
+ * range are written back to the page.
+ * 2. If we have multiple shared mappings of the same space in
+ * an object, we need to deal with the cache aliasing issues.
+ *
+ * Note that the pte lock will be held.
+ */
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr,
+ pte_t *ptep)
+{
+ unsigned long pfn = pte_pfn(*ptep);
+ struct address_space *mapping;
+ struct page *page;
+
+ if (!pfn_valid(pfn))
+ return;
+
+ /*
+ * The zero page is never written to, so never has any dirty
+ * cache lines, and therefore never needs to be flushed.
+ */
+ page = pfn_to_page(pfn);
+ if (page == ZERO_PAGE(0))
+ return;
+
+ mapping = page_mapping(page);
+ if (!test_and_set_bit(PG_dcache_clean, &page->flags))
+ __flush_dcache_page(mapping, page);
+ if (mapping)
+ if (vma->vm_flags & VM_EXEC)
+ __flush_icache_all();
+}
diff --git a/arch/unicore32/mm/pgd.c b/arch/unicore32/mm/pgd.c
new file mode 100644
index 000000000000..632cef7cd378
--- /dev/null
+++ b/arch/unicore32/mm/pgd.c
@@ -0,0 +1,102 @@
+/*
+ * linux/arch/unicore32/mm/pgd.c
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/mm.h>
+#include <linux/gfp.h>
+#include <linux/highmem.h>
+
+#include <asm/pgalloc.h>
+#include <asm/page.h>
+#include <asm/tlbflush.h>
+
+#include "mm.h"
+
+#define FIRST_KERNEL_PGD_NR (FIRST_USER_PGD_NR + USER_PTRS_PER_PGD)
+
+/*
+ * need to get a 4k page for level 1
+ */
+pgd_t *get_pgd_slow(struct mm_struct *mm)
+{
+ pgd_t *new_pgd, *init_pgd;
+ pmd_t *new_pmd, *init_pmd;
+ pte_t *new_pte, *init_pte;
+
+ new_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, 0);
+ if (!new_pgd)
+ goto no_pgd;
+
+ memset(new_pgd, 0, FIRST_KERNEL_PGD_NR * sizeof(pgd_t));
+
+ /*
+ * Copy over the kernel and IO PGD entries
+ */
+ init_pgd = pgd_offset_k(0);
+ memcpy(new_pgd + FIRST_KERNEL_PGD_NR, init_pgd + FIRST_KERNEL_PGD_NR,
+ (PTRS_PER_PGD - FIRST_KERNEL_PGD_NR) * sizeof(pgd_t));
+
+ clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t));
+
+ if (!vectors_high()) {
+ /*
+ * On UniCore, first page must always be allocated since it
+ * contains the machine vectors.
+ */
+ new_pmd = pmd_alloc(mm, (pud_t *)new_pgd, 0);
+ if (!new_pmd)
+ goto no_pmd;
+
+ new_pte = pte_alloc_map(mm, new_pmd, 0);
+ if (!new_pte)
+ goto no_pte;
+
+ init_pmd = pmd_offset((pud_t *)init_pgd, 0);
+ init_pte = pte_offset_map(init_pmd, 0);
+ set_pte(new_pte, *init_pte);
+ pte_unmap(init_pte);
+ pte_unmap(new_pte);
+ }
+
+ return new_pgd;
+
+no_pte:
+ pmd_free(mm, new_pmd);
+no_pmd:
+ free_pages((unsigned long)new_pgd, 0);
+no_pgd:
+ return NULL;
+}
+
+void free_pgd_slow(struct mm_struct *mm, pgd_t *pgd)
+{
+ pmd_t *pmd;
+ pgtable_t pte;
+
+ if (!pgd)
+ return;
+
+ /* pgd is always present and good */
+ pmd = pmd_off(pgd, 0);
+ if (pmd_none(*pmd))
+ goto free;
+ if (pmd_bad(*pmd)) {
+ pmd_ERROR(*pmd);
+ pmd_clear(pmd);
+ goto free;
+ }
+
+ pte = pmd_pgtable(*pmd);
+ pmd_clear(pmd);
+ pte_free(mm, pte);
+ pmd_free(mm, pmd);
+free:
+ free_pages((unsigned long) pgd, 0);
+}