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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/cpu/mtrr/cyrix.c | |
download | linux-fsl-qoriq-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/i386/kernel/cpu/mtrr/cyrix.c')
-rw-r--r-- | arch/i386/kernel/cpu/mtrr/cyrix.c | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/arch/i386/kernel/cpu/mtrr/cyrix.c b/arch/i386/kernel/cpu/mtrr/cyrix.c new file mode 100644 index 0000000..933b0dd --- /dev/null +++ b/arch/i386/kernel/cpu/mtrr/cyrix.c @@ -0,0 +1,364 @@ +#include <linux/init.h> +#include <linux/mm.h> +#include <asm/mtrr.h> +#include <asm/msr.h> +#include <asm/io.h> +#include "mtrr.h" + +int arr3_protected; + +static void +cyrix_get_arr(unsigned int reg, unsigned long *base, + unsigned int *size, mtrr_type * type) +{ + unsigned long flags; + unsigned char arr, ccr3, rcr, shift; + + arr = CX86_ARR_BASE + (reg << 1) + reg; /* avoid multiplication by 3 */ + + /* Save flags and disable interrupts */ + local_irq_save(flags); + + ccr3 = getCx86(CX86_CCR3); + setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */ + ((unsigned char *) base)[3] = getCx86(arr); + ((unsigned char *) base)[2] = getCx86(arr + 1); + ((unsigned char *) base)[1] = getCx86(arr + 2); + rcr = getCx86(CX86_RCR_BASE + reg); + setCx86(CX86_CCR3, ccr3); /* disable MAPEN */ + + /* Enable interrupts if it was enabled previously */ + local_irq_restore(flags); + shift = ((unsigned char *) base)[1] & 0x0f; + *base >>= PAGE_SHIFT; + + /* Power of two, at least 4K on ARR0-ARR6, 256K on ARR7 + * Note: shift==0xf means 4G, this is unsupported. + */ + if (shift) + *size = (reg < 7 ? 0x1UL : 0x40UL) << (shift - 1); + else + *size = 0; + + /* Bit 0 is Cache Enable on ARR7, Cache Disable on ARR0-ARR6 */ + if (reg < 7) { + switch (rcr) { + case 1: + *type = MTRR_TYPE_UNCACHABLE; + break; + case 8: + *type = MTRR_TYPE_WRBACK; + break; + case 9: + *type = MTRR_TYPE_WRCOMB; + break; + case 24: + default: + *type = MTRR_TYPE_WRTHROUGH; + break; + } + } else { + switch (rcr) { + case 0: + *type = MTRR_TYPE_UNCACHABLE; + break; + case 8: + *type = MTRR_TYPE_WRCOMB; + break; + case 9: + *type = MTRR_TYPE_WRBACK; + break; + case 25: + default: + *type = MTRR_TYPE_WRTHROUGH; + break; + } + } +} + +static int +cyrix_get_free_region(unsigned long base, unsigned long size) +/* [SUMMARY] Get a free ARR. + <base> The starting (base) address of the region. + <size> The size (in bytes) of the region. + [RETURNS] The index of the region on success, else -1 on error. +*/ +{ + int i; + mtrr_type ltype; + unsigned long lbase; + unsigned int lsize; + + /* If we are to set up a region >32M then look at ARR7 immediately */ + if (size > 0x2000) { + cyrix_get_arr(7, &lbase, &lsize, <ype); + if (lsize == 0) + return 7; + /* Else try ARR0-ARR6 first */ + } else { + for (i = 0; i < 7; i++) { + cyrix_get_arr(i, &lbase, &lsize, <ype); + if ((i == 3) && arr3_protected) + continue; + if (lsize == 0) + return i; + } + /* ARR0-ARR6 isn't free, try ARR7 but its size must be at least 256K */ + cyrix_get_arr(i, &lbase, &lsize, <ype); + if ((lsize == 0) && (size >= 0x40)) + return i; + } + return -ENOSPC; +} + +static u32 cr4 = 0; +static u32 ccr3; + +static void prepare_set(void) +{ + u32 cr0; + + /* Save value of CR4 and clear Page Global Enable (bit 7) */ + if ( cpu_has_pge ) { + cr4 = read_cr4(); + write_cr4(cr4 & (unsigned char) ~(1 << 7)); + } + + /* Disable and flush caches. Note that wbinvd flushes the TLBs as + a side-effect */ + cr0 = read_cr0() | 0x40000000; + wbinvd(); + write_cr0(cr0); + wbinvd(); + + /* Cyrix ARRs - everything else were excluded at the top */ + ccr3 = getCx86(CX86_CCR3); + + /* Cyrix ARRs - everything else were excluded at the top */ + setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); + +} + +static void post_set(void) +{ + /* Flush caches and TLBs */ + wbinvd(); + + /* Cyrix ARRs - everything else was excluded at the top */ + setCx86(CX86_CCR3, ccr3); + + /* Enable caches */ + write_cr0(read_cr0() & 0xbfffffff); + + /* Restore value of CR4 */ + if ( cpu_has_pge ) + write_cr4(cr4); +} + +static void cyrix_set_arr(unsigned int reg, unsigned long base, + unsigned long size, mtrr_type type) +{ + unsigned char arr, arr_type, arr_size; + + arr = CX86_ARR_BASE + (reg << 1) + reg; /* avoid multiplication by 3 */ + + /* count down from 32M (ARR0-ARR6) or from 2G (ARR7) */ + if (reg >= 7) + size >>= 6; + + size &= 0x7fff; /* make sure arr_size <= 14 */ + for (arr_size = 0; size; arr_size++, size >>= 1) ; + + if (reg < 7) { + switch (type) { + case MTRR_TYPE_UNCACHABLE: + arr_type = 1; + break; + case MTRR_TYPE_WRCOMB: + arr_type = 9; + break; + case MTRR_TYPE_WRTHROUGH: + arr_type = 24; + break; + default: + arr_type = 8; + break; + } + } else { + switch (type) { + case MTRR_TYPE_UNCACHABLE: + arr_type = 0; + break; + case MTRR_TYPE_WRCOMB: + arr_type = 8; + break; + case MTRR_TYPE_WRTHROUGH: + arr_type = 25; + break; + default: + arr_type = 9; + break; + } + } + + prepare_set(); + + base <<= PAGE_SHIFT; + setCx86(arr, ((unsigned char *) &base)[3]); + setCx86(arr + 1, ((unsigned char *) &base)[2]); + setCx86(arr + 2, (((unsigned char *) &base)[1]) | arr_size); + setCx86(CX86_RCR_BASE + reg, arr_type); + + post_set(); +} + +typedef struct { + unsigned long base; + unsigned int size; + mtrr_type type; +} arr_state_t; + +static arr_state_t arr_state[8] __initdata = { + {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, + {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL} +}; + +static unsigned char ccr_state[7] __initdata = { 0, 0, 0, 0, 0, 0, 0 }; + +static void cyrix_set_all(void) +{ + int i; + + prepare_set(); + + /* the CCRs are not contiguous */ + for (i = 0; i < 4; i++) + setCx86(CX86_CCR0 + i, ccr_state[i]); + for (; i < 7; i++) + setCx86(CX86_CCR4 + i, ccr_state[i]); + for (i = 0; i < 8; i++) + cyrix_set_arr(i, arr_state[i].base, + arr_state[i].size, arr_state[i].type); + + post_set(); +} + +#if 0 +/* + * On Cyrix 6x86(MX) and M II the ARR3 is special: it has connection + * with the SMM (System Management Mode) mode. So we need the following: + * Check whether SMI_LOCK (CCR3 bit 0) is set + * if it is set, write a warning message: ARR3 cannot be changed! + * (it cannot be changed until the next processor reset) + * if it is reset, then we can change it, set all the needed bits: + * - disable access to SMM memory through ARR3 range (CCR1 bit 7 reset) + * - disable access to SMM memory (CCR1 bit 2 reset) + * - disable SMM mode (CCR1 bit 1 reset) + * - disable write protection of ARR3 (CCR6 bit 1 reset) + * - (maybe) disable ARR3 + * Just to be sure, we enable ARR usage by the processor (CCR5 bit 5 set) + */ +static void __init +cyrix_arr_init(void) +{ + struct set_mtrr_context ctxt; + unsigned char ccr[7]; + int ccrc[7] = { 0, 0, 0, 0, 0, 0, 0 }; +#ifdef CONFIG_SMP + int i; +#endif + + /* flush cache and enable MAPEN */ + set_mtrr_prepare_save(&ctxt); + set_mtrr_cache_disable(&ctxt); + + /* Save all CCRs locally */ + ccr[0] = getCx86(CX86_CCR0); + ccr[1] = getCx86(CX86_CCR1); + ccr[2] = getCx86(CX86_CCR2); + ccr[3] = ctxt.ccr3; + ccr[4] = getCx86(CX86_CCR4); + ccr[5] = getCx86(CX86_CCR5); + ccr[6] = getCx86(CX86_CCR6); + + if (ccr[3] & 1) { + ccrc[3] = 1; + arr3_protected = 1; + } else { + /* Disable SMM mode (bit 1), access to SMM memory (bit 2) and + * access to SMM memory through ARR3 (bit 7). + */ + if (ccr[1] & 0x80) { + ccr[1] &= 0x7f; + ccrc[1] |= 0x80; + } + if (ccr[1] & 0x04) { + ccr[1] &= 0xfb; + ccrc[1] |= 0x04; + } + if (ccr[1] & 0x02) { + ccr[1] &= 0xfd; + ccrc[1] |= 0x02; + } + arr3_protected = 0; + if (ccr[6] & 0x02) { + ccr[6] &= 0xfd; + ccrc[6] = 1; /* Disable write protection of ARR3 */ + setCx86(CX86_CCR6, ccr[6]); + } + /* Disable ARR3. This is safe now that we disabled SMM. */ + /* cyrix_set_arr_up (3, 0, 0, 0, FALSE); */ + } + /* If we changed CCR1 in memory, change it in the processor, too. */ + if (ccrc[1]) + setCx86(CX86_CCR1, ccr[1]); + + /* Enable ARR usage by the processor */ + if (!(ccr[5] & 0x20)) { + ccr[5] |= 0x20; + ccrc[5] = 1; + setCx86(CX86_CCR5, ccr[5]); + } +#ifdef CONFIG_SMP + for (i = 0; i < 7; i++) + ccr_state[i] = ccr[i]; + for (i = 0; i < 8; i++) + cyrix_get_arr(i, + &arr_state[i].base, &arr_state[i].size, + &arr_state[i].type); +#endif + + set_mtrr_done(&ctxt); /* flush cache and disable MAPEN */ + + if (ccrc[5]) + printk(KERN_INFO "mtrr: ARR usage was not enabled, enabled manually\n"); + if (ccrc[3]) + printk(KERN_INFO "mtrr: ARR3 cannot be changed\n"); +/* + if ( ccrc[1] & 0x80) printk ("mtrr: SMM memory access through ARR3 disabled\n"); + if ( ccrc[1] & 0x04) printk ("mtrr: SMM memory access disabled\n"); + if ( ccrc[1] & 0x02) printk ("mtrr: SMM mode disabled\n"); +*/ + if (ccrc[6]) + printk(KERN_INFO "mtrr: ARR3 was write protected, unprotected\n"); +} +#endif + +static struct mtrr_ops cyrix_mtrr_ops = { + .vendor = X86_VENDOR_CYRIX, +// .init = cyrix_arr_init, + .set_all = cyrix_set_all, + .set = cyrix_set_arr, + .get = cyrix_get_arr, + .get_free_region = cyrix_get_free_region, + .validate_add_page = generic_validate_add_page, + .have_wrcomb = positive_have_wrcomb, +}; + +int __init cyrix_init_mtrr(void) +{ + set_mtrr_ops(&cyrix_mtrr_ops); + return 0; +} + +//arch_initcall(cyrix_init_mtrr); |