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Diffstat (limited to 'arch/i386/kernel/cpu/mtrr/cyrix.c')
-rw-r--r--arch/i386/kernel/cpu/mtrr/cyrix.c364
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, &ltype);
+ if (lsize == 0)
+ return 7;
+ /* Else try ARR0-ARR6 first */
+ } else {
+ for (i = 0; i < 7; i++) {
+ cyrix_get_arr(i, &lbase, &lsize, &ltype);
+ 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, &ltype);
+ 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);
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