diff --git a/arch/sh/kernel/head_32.S b/arch/sh/kernel/head_32.S index e5d421db4c83..8ee31a0b973e 100644 --- a/arch/sh/kernel/head_32.S +++ b/arch/sh/kernel/head_32.S @@ -3,6 +3,7 @@ * arch/sh/kernel/head.S * * Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima + * Copyright (C) 2010 Matt Fleming * * 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 @@ -84,6 +85,236 @@ ENTRY(_stext) ldc r0, r7_bank ! ... and initial thread_info #endif +#if defined(CONFIG_PMB) && !defined(CONFIG_PMB_LEGACY) + /* + * Reconfigure the initial PMB mappings setup by the hardware. + * + * When we boot in 32-bit MMU mode there are 2 PMB entries already + * setup for us. + * + * Entry VPN PPN V SZ C UB WT + * --------------------------------------------------------------- + * 0 0x80000000 0x00000000 1 512MB 1 0 1 + * 1 0xA0000000 0x00000000 1 512MB 0 0 0 + * + * But we reprogram them here because we want complete control over + * our address space and the initial mappings may not map PAGE_OFFSET + * to __MEMORY_START (or even map all of our RAM). + * + * Once we've setup cached and uncached mappings for all of RAM we + * clear the rest of the PMB entries. + * + * This clearing also deals with the fact that PMB entries can persist + * across reboots. The PMB could have been left in any state when the + * reboot occurred, so to be safe we clear all entries and start with + * with a clean slate. + */ + + mov.l .LMMUCR, r1 /* Flush the TLB */ + mov.l @r1, r0 + or #MMUCR_TI, r0 + mov.l r0, @r1 + + mov.l .LMEMORY_SIZE, r5 + mov r5, r7 + + mov #PMB_E_SHIFT, r0 + mov #0x1, r4 + shld r0, r4 + + mov.l .LFIRST_DATA_ENTRY, r0 + mov.l .LPMB_DATA, r1 + mov.l .LFIRST_ADDR_ENTRY, r2 + mov.l .LPMB_ADDR, r3 + + mov #0, r10 + + /* + * r0 = PMB_DATA data field + * r1 = PMB_DATA address field + * r2 = PMB_ADDR data field + * r3 = PMB_ADDR address field + * r4 = PMB_E_SHIFT + * r5 = remaining amount of RAM to map + * r6 = PMB mapping size we're trying to use + * r7 = cached_to_uncached + * r8 = scratch register + * r9 = scratch register + * r10 = number of PMB entries we've setup + */ +.L512: + mov #(512 >> 4), r6 + shll16 r6 + shll8 r6 + + cmp/hi r5, r6 + bt .L128 + + mov #(PMB_SZ_512M >> 2), r9 + shll2 r9 + + /* + * Cached mapping + */ + mov #PMB_C, r8 + or r0, r8 + or r9, r8 + mov.l r8, @r1 + mov.l r2, @r3 + + add r4, r1 /* Increment to the next PMB_DATA entry */ + add r4, r3 /* Increment to the next PMB_ADDR entry */ + + add #1, r10 /* Increment number of PMB entries */ + + /* + * Uncached mapping + */ + mov #(PMB_UB >> 8), r8 + shll8 r8 + + or r0, r8 + or r9, r8 + mov.l r8, @r1 + mov r2, r8 + add r7, r8 + mov.l r8, @r3 + + add r4, r1 /* Increment to the next PMB_DATA entry */ + add r4, r3 /* Increment to the next PMB_ADDR entry */ + + add #1, r10 /* Increment number of PMB entries */ + + sub r6, r5 + add r6, r0 + add r6, r2 + + bra .L512 + +.L128: + mov #(128 >> 4), r6 + shll16 r6 + shll8 r6 + + cmp/hi r5, r6 + bt .L64 + + mov #(PMB_SZ_128M >> 2), r9 + shll2 r9 + + /* + * Cached mapping + */ + mov #PMB_C, r8 + or r0, r8 + or r9, r8 + mov.l r8, @r1 + mov.l r2, @r3 + + add r4, r1 /* Increment to the next PMB_DATA entry */ + add r4, r3 /* Increment to the next PMB_ADDR entry */ + + add #1, r10 /* Increment number of PMB entries */ + + /* + * Uncached mapping + */ + mov #(PMB_UB >> 8), r8 + shll8 r8 + + or r0, r8 + or r9, r8 + mov.l r8, @r1 + mov r2, r8 + add r7, r8 + mov.l r8, @r3 + + add r4, r1 /* Increment to the next PMB_DATA entry */ + add r4, r3 /* Increment to the next PMB_ADDR entry */ + + add #1, r10 /* Increment number of PMB entries */ + + sub r6, r5 + add r6, r0 + add r6, r2 + + bra .L128 + +.L64: + mov #(64 >> 4), r6 + shll16 r6 + shll8 r6 + + cmp/hi r5, r6 + bt .Ldone + + mov #(PMB_SZ_64M >> 2), r9 + shll2 r9 + + /* + * Cached mapping + */ + mov #PMB_C, r8 + or r0, r8 + or r9, r8 + mov.l r8, @r1 + mov.l r2, @r3 + + add r4, r1 /* Increment to the next PMB_DATA entry */ + add r4, r3 /* Increment to the next PMB_ADDR entry */ + + add #1, r10 /* Increment number of PMB entries */ + + /* + * Uncached mapping + */ + mov #(PMB_UB >> 8), r8 + shll8 r8 + + or r0, r8 + or r9, r8 + mov.l r8, @r1 + mov r2, r8 + add r7, r8 + mov.l r8, @r3 + + add r4, r1 /* Increment to the next PMB_DATA entry */ + add r4, r3 /* Increment to the next PMB_ADDR entry */ + + add #1, r10 /* Increment number of PMB entries */ + + sub r6, r5 + add r6, r0 + add r6, r2 + + bra .L64 + +.Ldone: + /* Update cached_to_uncached */ + mov.l .Lcached_to_uncached, r0 + mov.l r7, @r0 + + /* + * Clear the remaining PMB entries. + * + * r3 = entry to begin clearing from + * r10 = number of entries we've setup so far + */ + mov #0, r1 + mov #PMB_ENTRY_MAX, r0 + +.Lagain: + mov.l r1, @r3 /* Clear PMB_ADDR entry */ + add #1, r10 /* Increment the loop counter */ + cmp/eq r0, r10 + bf/s .Lagain + add r4, r3 /* Increment to the next PMB_ADDR entry */ + + mov.l 6f, r0 + icbi @r0 + +#endif /* !CONFIG_PMB_LEGACY */ + #ifndef CONFIG_SH_NO_BSS_INIT /* * Don't clear BSS if running on slow platforms such as an RTL simulation, @@ -133,3 +364,13 @@ ENTRY(stack_start) 5: .long start_kernel 6: .long sh_cpu_init 7: .long init_thread_union + +#if defined(CONFIG_PMB) && !defined(CONFIG_PMB_LEGACY) +.LPMB_ADDR: .long PMB_ADDR +.LPMB_DATA: .long PMB_DATA +.LFIRST_ADDR_ENTRY: .long PAGE_OFFSET | PMB_V +.LFIRST_DATA_ENTRY: .long __MEMORY_START | PMB_V +.LMMUCR: .long MMUCR +.Lcached_to_uncached: .long cached_to_uncached +.LMEMORY_SIZE: .long __MEMORY_SIZE +#endif diff --git a/arch/sh/mm/pmb.c b/arch/sh/mm/pmb.c index 8f7dbf183fb0..b796b6c021b4 100644 --- a/arch/sh/mm/pmb.c +++ b/arch/sh/mm/pmb.c @@ -3,11 +3,8 @@ * * Privileged Space Mapping Buffer (PMB) Support. * - * Copyright (C) 2005 - 2010 Paul Mundt - * - * P1/P2 Section mapping definitions from map32.h, which was: - * - * Copyright 2003 (c) Lineo Solutions,Inc. + * Copyright (C) 2005 - 2010 Paul Mundt + * Copyright (C) 2010 Matt Fleming * * 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 @@ -280,12 +277,119 @@ static void __pmb_unmap(struct pmb_entry *pmbe) } #ifdef CONFIG_PMB_LEGACY +static inline unsigned int pmb_ppn_in_range(unsigned long ppn) +{ + return ppn >= __MEMORY_START && ppn < __MEMORY_START + __MEMORY_SIZE; +} + static int pmb_apply_legacy_mappings(void) +{ + unsigned int applied = 0; + int i; + + pr_info("PMB: Preserving legacy mappings:\n"); + + /* + * The following entries are setup by the bootloader. + * + * Entry VPN PPN V SZ C UB + * -------------------------------------------------------- + * 0 0xA0000000 0x00000000 1 64MB 0 0 + * 1 0xA4000000 0x04000000 1 16MB 0 0 + * 2 0xA6000000 0x08000000 1 16MB 0 0 + * 9 0x88000000 0x48000000 1 128MB 1 1 + * 10 0x90000000 0x50000000 1 128MB 1 1 + * 11 0x98000000 0x58000000 1 128MB 1 1 + * 13 0xA8000000 0x48000000 1 128MB 0 0 + * 14 0xB0000000 0x50000000 1 128MB 0 0 + * 15 0xB8000000 0x58000000 1 128MB 0 0 + * + * The only entries the we need are the ones that map the kernel + * at the cached and uncached addresses. + */ + for (i = 0; i < PMB_ENTRY_MAX; i++) { + unsigned long addr, data; + unsigned long addr_val, data_val; + unsigned long ppn, vpn; + + addr = mk_pmb_addr(i); + data = mk_pmb_data(i); + + addr_val = __raw_readl(addr); + data_val = __raw_readl(data); + + /* + * Skip over any bogus entries + */ + if (!(data_val & PMB_V) || !(addr_val & PMB_V)) + continue; + + ppn = data_val & PMB_PFN_MASK; + vpn = addr_val & PMB_PFN_MASK; + + /* + * Only preserve in-range mappings. + */ + if (pmb_ppn_in_range(ppn)) { + unsigned int size; + char *sz_str = NULL; + + size = data_val & PMB_SZ_MASK; + + sz_str = (size == PMB_SZ_16M) ? " 16MB": + (size == PMB_SZ_64M) ? " 64MB": + (size == PMB_SZ_128M) ? "128MB": + "512MB"; + + pr_info("\t0x%08lx -> 0x%08lx [ %s %scached ]\n", + vpn >> PAGE_SHIFT, ppn >> PAGE_SHIFT, sz_str, + (data_val & PMB_C) ? "" : "un"); + + applied++; + } else { + /* + * Invalidate anything out of bounds. + */ + __raw_writel(addr_val & ~PMB_V, addr); + __raw_writel(data_val & ~PMB_V, data); + } + } + + return (applied == 0); +} +#else +static inline int pmb_apply_legacy_mappings(void) +{ + return 1; +} +#endif + +int __uses_jump_to_uncached pmb_init(void) { int i; unsigned long addr, data; - unsigned int applied = 0; + unsigned long ret; + jump_to_uncached(); + + /* + * Attempt to apply the legacy boot mappings if configured. If + * this is successful then we simply carry on with those and + * don't bother establishing additional memory mappings. Dynamic + * device mappings through pmb_remap() can still be bolted on + * after this. + */ + ret = pmb_apply_legacy_mappings(); + if (ret == 0) { + back_to_cached(); + return 0; + } + + /* + * Sync our software copy of the PMB mappings with those in + * hardware. The mappings in the hardware PMB were either set up + * by the bootloader or very early on by the kernel. + */ for (i = 0; i < PMB_ENTRY_MAX; i++) { struct pmb_entry *pmbe; unsigned long vpn, ppn, flags; @@ -318,60 +422,10 @@ static int pmb_apply_legacy_mappings(void) pmbe = pmb_alloc(vpn, ppn, flags, i); WARN_ON(IS_ERR(pmbe)); - - applied++; } - return (applied == 0); -} -#else -static inline int pmb_apply_legacy_mappings(void) -{ - return 1; -} -#endif - -int __uses_jump_to_uncached pmb_init(void) -{ - unsigned int i; - unsigned long size, ret; - - jump_to_uncached(); - - /* - * Attempt to apply the legacy boot mappings if configured. If - * this is successful then we simply carry on with those and - * don't bother establishing additional memory mappings. Dynamic - * device mappings through pmb_remap() can still be bolted on - * after this. - */ - ret = pmb_apply_legacy_mappings(); - if (ret == 0) { - back_to_cached(); - return 0; - } - - /* - * Insert PMB entries for the P1 and P2 areas so that, after - * we've switched the MMU to 32-bit mode, the semantics of P1 - * and P2 are the same as in 29-bit mode, e.g. - * - * P1 - provides a cached window onto physical memory - * P2 - provides an uncached window onto physical memory - */ - size = (unsigned long)__MEMORY_START + __MEMORY_SIZE; - - ret = pmb_remap(P1SEG, 0x00000000, size, PMB_C); - BUG_ON(ret != size); - - ret = pmb_remap(P2SEG, 0x00000000, size, PMB_WT | PMB_UB); - BUG_ON(ret != size); - ctrl_outl(0, PMB_IRMCR); - /* PMB.SE and UB[7] */ - ctrl_outl(PASCR_SE | (1 << 7), PMB_PASCR); - /* Flush out the TLB */ i = ctrl_inl(MMUCR); i |= MMUCR_TI;