@@ -193,6 +193,10 @@ struct mmu_psize_def
{
unsigned int shift; /* number of bits */
unsigned int enc; /* PTE encoding */
+ unsigned int ind; /* Corresponding indirect page size shift */
+ unsigned int flags;
+#define MMU_PAGE_SIZE_DIRECT 0x1 /* Supported as a direct size */
+#define MMU_PAGE_SIZE_INDIRECT 0x2 /* Supported as an indirect size */
};
extern struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
@@ -62,6 +62,7 @@
#define SPRN_TLB0PS 0x158 /* TLB 0 Page Size Register */
#define SPRN_MAS5_MAS6 0x15c /* MMU Assist Register 5 || 6 */
#define SPRN_MAS8_MAS1 0x15d /* MMU Assist Register 8 || 1 */
+#define SPRN_EPTCFG 0x15e /* Embedded Page Table Config */
#define SPRN_MAS7_MAS3 0x174 /* MMU Assist Register 7 || 3 */
#define SPRN_MAS0_MAS1 0x175 /* MMU Assist Register 0 || 1 */
#define SPRN_IVOR0 0x190 /* Interrupt Vector Offset Register 0 */
@@ -46,6 +46,7 @@
struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
[MMU_PAGE_4K] = {
.shift = 12,
+ .ind = 20,
.enc = BOOK3E_PAGESZ_4K,
},
[MMU_PAGE_16K] = {
@@ -54,6 +55,7 @@ struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
},
[MMU_PAGE_64K] = {
.shift = 16,
+ .ind = 28,
.enc = BOOK3E_PAGESZ_64K,
},
[MMU_PAGE_1M] = {
@@ -62,6 +64,7 @@ struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
},
[MMU_PAGE_16M] = {
.shift = 24,
+ .ind = 36,
.enc = BOOK3E_PAGESZ_16M,
},
[MMU_PAGE_256M] = {
@@ -344,16 +347,108 @@ void tlb_flush_pgtable(struct mmu_gather *tlb, unsigned long address)
}
}
-/*
- * Early initialization of the MMU TLB code
- */
-static void __early_init_mmu(int boot_cpu)
+static void setup_page_sizes(void)
+{
+ unsigned int tlb0cfg = mfspr(SPRN_TLB0CFG);
+ unsigned int tlb0ps = mfspr(SPRN_TLB0PS);
+ unsigned int eptcfg = mfspr(SPRN_EPTCFG);
+ int i, psize;
+
+ /* Look for supported direct sizes */
+ for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+ struct mmu_psize_def *def = &mmu_psize_defs[psize];
+
+ if (tlb0ps & (1U << (def->shift - 10)))
+ def->flags |= MMU_PAGE_SIZE_DIRECT;
+ }
+
+ /* Indirect page sizes supported ? */
+ if ((tlb0cfg & TLBnCFG_IND) == 0)
+ goto no_indirect;
+
+ /* Now, we only deal with one IND page size for each
+ * direct size. Hopefully all implementations today are
+ * unambiguous, but we might want to be careful in the
+ * future.
+ */
+ for (i = 0; i < 3; i++) {
+ unsigned int ps, sps;
+
+ sps = eptcfg & 0x1f;
+ eptcfg >>= 5;
+ ps = eptcfg & 0x1f;
+ eptcfg >>= 5;
+ if (!ps || !sps)
+ continue;
+ for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
+ struct mmu_psize_def *def = &mmu_psize_defs[psize];
+
+ if (ps == (def->shift - 10))
+ def->flags |= MMU_PAGE_SIZE_INDIRECT;
+ if (sps == (def->shift - 10))
+ def->ind = ps + 10;
+ }
+ }
+ no_indirect:
+
+ /* Cleanup array and print summary */
+ pr_info("MMU: Supported page sizes\n");
+ for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+ struct mmu_psize_def *def = &mmu_psize_defs[psize];
+ const char *__page_type_names[] = {
+ "unsupported",
+ "direct",
+ "indirect",
+ "direct & indirect"
+ };
+ if (def->flags == 0) {
+ def->shift = 0;
+ continue;
+ }
+ pr_info(" %8ld KB as %s\n", 1ul << (def->shift - 10),
+ __page_type_names[def->flags & 0x3]);
+ }
+}
+
+static void setup_mmu_htw(void)
{
extern unsigned int interrupt_base_book3e;
extern unsigned int exc_data_tlb_miss_htw_book3e;
extern unsigned int exc_instruction_tlb_miss_htw_book3e;
unsigned int *ibase = &interrupt_base_book3e;
+
+ /* Check if HW tablewalk is present, and if yes, enable it by:
+ *
+ * - patching the TLB miss handlers to branch to the
+ * one dedicates to it
+ *
+ * - setting the global book3e_htw_enabled
+ */
+ unsigned int tlb0cfg = mfspr(SPRN_TLB0CFG);
+
+ if ((tlb0cfg & TLBnCFG_IND) &&
+ (tlb0cfg & TLBnCFG_PT)) {
+ /* Our exceptions vectors start with a NOP and -then- a branch
+ * to deal with single stepping from userspace which stops on
+ * the second instruction. Thus we need to patch the second
+ * instruction of the exception, not the first one
+ */
+ patch_branch(ibase + (0x1c0 / 4) + 1,
+ (unsigned long)&exc_data_tlb_miss_htw_book3e, 0);
+ patch_branch(ibase + (0x1e0 / 4) + 1,
+ (unsigned long)&exc_instruction_tlb_miss_htw_book3e, 0);
+ book3e_htw_enabled = 1;
+ }
+ pr_info("MMU: Book3E Page Tables %s\n",
+ book3e_htw_enabled ? "Enabled" : "Disabled");
+}
+
+/*
+ * Early initialization of the MMU TLB code
+ */
+static void __early_init_mmu(int boot_cpu)
+{
unsigned int mas4;
/* XXX This will have to be decided at runtime, but right
@@ -370,40 +465,17 @@ static void __early_init_mmu(int boot_cpu)
*/
mmu_vmemmap_psize = MMU_PAGE_16M;
- /* Check if HW tablewalk is present, and if yes, enable it by:
- *
- * - patching the TLB miss handlers to branch to the
- * one dedicates to it
- *
- * - setting the global book3e_htw_enabled
- *
- * - Set MAS4:INDD and default page size
- */
-
/* XXX This code only checks for TLB 0 capabilities and doesn't
* check what page size combos are supported by the HW. It
* also doesn't handle the case where a separate array holds
* the IND entries from the array loaded by the PT.
*/
if (boot_cpu) {
- unsigned int tlb0cfg = mfspr(SPRN_TLB0CFG);
-
- /* Check if HW loader is supported */
- if ((tlb0cfg & TLBnCFG_IND) &&
- (tlb0cfg & TLBnCFG_PT)) {
- /* Our exceptions vectors start with a NOP and -then- a branch
- * to deal with single stepping from userspace which stops on
- * the second instruction. Thus we need to patch the second
- * instruction of the exception, not the first one
- */
- patch_branch(ibase + (0x1c0 / 4) + 1,
- (unsigned long)&exc_data_tlb_miss_htw_book3e, 0);
- patch_branch(ibase + (0x1e0 / 4) + 1,
- (unsigned long)&exc_instruction_tlb_miss_htw_book3e, 0);
- book3e_htw_enabled = 1;
- }
- pr_info("MMU: Book3E Page Tables %s\n",
- book3e_htw_enabled ? "Enabled" : "Disabled");
+ /* Look for supported page sizes */
+ setup_page_sizes();
+
+ /* Look for HW tablewalk support */
+ setup_mmu_htw();
}
/* Set MAS4 based on page table setting */
Use the MMU config registers to scan for available direct and indirect page sizes and print out the result. Will be needed for future hugetlbfs implementation. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- arch/powerpc/include/asm/mmu-book3e.h | 4 + arch/powerpc/include/asm/reg_booke.h | 1 + arch/powerpc/mm/tlb_nohash.c | 136 +++++++++++++++++++++++++-------- 3 files changed, 109 insertions(+), 32 deletions(-)