sh: tlb debugfs support.

Export the status of the utlb and itlb entries through debugfs.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

diff --git a/arch/sh/include/cpu-sh4/cpu/mmu_context.h b/arch/sh/include/cpu-sh4/cpu/mmu_context.h
index 5963124..2941be6 100644 (file)
--- a/arch/sh/include/cpu-sh4/cpu/mmu_context.h
+++ b/arch/sh/include/cpu-sh4/cpu/mmu_context.h
@@ -19,10 +19,17 @@
 
 #define MMUCR          0xFF000010      /* MMU Control Register */
 
+#define MMU_TLB_ENTRY_SHIFT    8
+
 #define MMU_ITLB_ADDRESS_ARRAY  0xF2000000
 #define MMU_ITLB_ADDRESS_ARRAY2        0xF2800000
+#define MMU_ITLB_DATA_ARRAY    0xF3000000
+#define MMU_ITLB_DATA_ARRAY2   0xF3800000
+
 #define MMU_UTLB_ADDRESS_ARRAY 0xF6000000
 #define MMU_UTLB_ADDRESS_ARRAY2        0xF6800000
+#define MMU_UTLB_DATA_ARRAY    0xF7000000
+#define MMU_UTLB_DATA_ARRAY2   0xF7800000
 #define MMU_PAGE_ASSOC_BIT     0x80
 
 #define MMUCR_TI               (1<<2)

diff --git a/arch/sh/mm/Makefile b/arch/sh/mm/Makefile
index 3dc8a8a..c73018a 100644 (file)
--- a/arch/sh/mm/Makefile
+++ b/arch/sh/mm/Makefile
@@ -18,13 +18,14 @@ mmu-$(CONFIG_MMU)   := extable_$(BITS).o fault_$(BITS).o \
                           ioremap.o kmap.o pgtable.o tlbflush_$(BITS).o
 
 obj-y                  += $(mmu-y)
-obj-$(CONFIG_DEBUG_FS) += asids-debugfs.o
 
-ifdef CONFIG_DEBUG_FS
-obj-$(CONFIG_CPU_SH4)  += cache-debugfs.o
+debugfs-y                      := asids-debugfs.o
+ifndef CONFIG_CACHE_OFF
+debugfs-$(CONFIG_CPU_SH4)      += cache-debugfs.o
 endif
 
 ifdef CONFIG_MMU
+debugfs-$(CONFIG_CPU_SH4)      += tlb-debugfs.o
 tlb-$(CONFIG_CPU_SH3)          := tlb-sh3.o
 tlb-$(CONFIG_CPU_SH4)          := tlb-sh4.o tlb-urb.o
 tlb-$(CONFIG_CPU_SH5)          := tlb-sh5.o
@@ -32,6 +33,7 @@ tlb-$(CONFIG_CPU_HAS_PTEAEX)  := tlb-pteaex.o tlb-urb.o
 obj-y                          += $(tlb-y)
 endif
 
+obj-$(CONFIG_DEBUG_FS)         += $(debugfs-y)
 obj-$(CONFIG_HUGETLB_PAGE)     += hugetlbpage.o
 obj-$(CONFIG_PMB)              += pmb.o
 obj-$(CONFIG_NUMA)             += numa.o

diff --git a/arch/sh/mm/tlb-debugfs.c b/arch/sh/mm/tlb-debugfs.c
new file mode 100644 (file)
index 0000000..229bf75
--- /dev/null
+++ b/arch/sh/mm/tlb-debugfs.c
@@ -0,0 +1,179 @@
+/*
+ * arch/sh/mm/tlb-debugfs.c
+ *
+ * debugfs ops for SH-4 ITLB/UTLBs.
+ *
+ * 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
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <asm/processor.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
+
+enum tlb_type {
+       TLB_TYPE_ITLB,
+       TLB_TYPE_UTLB,
+};
+
+static struct {
+       int bits;
+       const char *size;
+} tlb_sizes[] = {
+       { 0x0, "  1KB" },
+       { 0x1, "  4KB" },
+       { 0x2, "  8KB" },
+       { 0x4, " 64KB" },
+       { 0x5, "256KB" },
+       { 0x7, "  1MB" },
+       { 0x8, "  4MB" },
+       { 0xc, " 64MB" },
+};
+
+static int tlb_seq_show(struct seq_file *file, void *iter)
+{
+       unsigned int tlb_type = (unsigned int)file->private;
+       unsigned long addr1, addr2, data1, data2;
+       unsigned long flags;
+       unsigned long mmucr;
+       unsigned int nentries, entry;
+       unsigned int urb;
+
+       mmucr = __raw_readl(MMUCR);
+       if ((mmucr & 0x1) == 0) {
+               seq_printf(file, "address translation disabled\n");
+               return 0;
+       }
+
+       if (tlb_type == TLB_TYPE_ITLB) {
+               addr1 = MMU_ITLB_ADDRESS_ARRAY;
+               addr2 = MMU_ITLB_ADDRESS_ARRAY2;
+               data1 = MMU_ITLB_DATA_ARRAY;
+               data2 = MMU_ITLB_DATA_ARRAY2;
+               nentries = 4;
+       } else {
+               addr1 = MMU_UTLB_ADDRESS_ARRAY;
+               addr2 = MMU_UTLB_ADDRESS_ARRAY2;
+               data1 = MMU_UTLB_DATA_ARRAY;
+               data2 = MMU_UTLB_DATA_ARRAY2;
+               nentries = 64;
+       }
+
+       local_irq_save(flags);
+       jump_to_uncached();
+
+       urb = (mmucr & MMUCR_URB) >> MMUCR_URB_SHIFT;
+
+       /* Make the "entry >= urb" test fail. */
+       if (urb == 0)
+               urb = MMUCR_URB_NENTRIES + 1;
+
+       if (tlb_type == TLB_TYPE_ITLB) {
+               addr1 = MMU_ITLB_ADDRESS_ARRAY;
+               addr2 = MMU_ITLB_ADDRESS_ARRAY2;
+               data1 = MMU_ITLB_DATA_ARRAY;
+               data2 = MMU_ITLB_DATA_ARRAY2;
+               nentries = 4;
+       } else {
+               addr1 = MMU_UTLB_ADDRESS_ARRAY;
+               addr2 = MMU_UTLB_ADDRESS_ARRAY2;
+               data1 = MMU_UTLB_DATA_ARRAY;
+               data2 = MMU_UTLB_DATA_ARRAY2;
+               nentries = 64;
+       }
+
+       seq_printf(file, "entry:     vpn        ppn     asid  size valid wired\n");
+
+       for (entry = 0; entry < nentries; entry++) {
+               unsigned long vpn, ppn, asid, size;
+               unsigned long valid;
+               unsigned long val;
+               const char *sz = "    ?";
+               int i;
+
+               val = __raw_readl(addr1 | (entry << MMU_TLB_ENTRY_SHIFT));
+               ctrl_barrier();
+               vpn = val & 0xfffffc00;
+               valid = val & 0x100;
+
+               val = __raw_readl(addr2 | (entry << MMU_TLB_ENTRY_SHIFT));
+               ctrl_barrier();
+               asid = val & MMU_CONTEXT_ASID_MASK;
+
+               val = __raw_readl(data1 | (entry << MMU_TLB_ENTRY_SHIFT));
+               ctrl_barrier();
+               ppn = (val & 0x0ffffc00) << 4;
+
+               val = __raw_readl(data2 | (entry << MMU_TLB_ENTRY_SHIFT));
+               ctrl_barrier();
+               size = (val & 0xf0) >> 4;
+
+               for (i = 0; i < ARRAY_SIZE(tlb_sizes); i++) {
+                       if (tlb_sizes[i].bits == size)
+                               break;
+               }
+
+               if (i != ARRAY_SIZE(tlb_sizes))
+                       sz = tlb_sizes[i].size;
+
+               seq_printf(file, "%2d:    0x%08lx 0x%08lx %5lu %s   %s     %s\n",
+                          entry, vpn, ppn, asid,
+                          sz, valid ? "V" : "-",
+                          (urb <= entry) ? "W" : "-");
+       }
+
+       back_to_cached();
+       local_irq_restore(flags);
+
+       return 0;
+}
+
+static int tlb_debugfs_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, tlb_seq_show, inode->i_private);
+}
+
+static const struct file_operations tlb_debugfs_fops = {
+       .owner          = THIS_MODULE,
+       .open           = tlb_debugfs_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
+static int __init tlb_debugfs_init(void)
+{
+       struct dentry *itlb, *utlb;
+
+       itlb = debugfs_create_file("itlb", S_IRUSR, sh_debugfs_root,
+                                  (unsigned int *)TLB_TYPE_ITLB,
+                                  &tlb_debugfs_fops);
+       if (unlikely(!itlb))
+               return -ENOMEM;
+       if (IS_ERR(itlb))
+               return PTR_ERR(itlb);
+
+       utlb = debugfs_create_file("utlb", S_IRUSR, sh_debugfs_root,
+                                  (unsigned int *)TLB_TYPE_UTLB,
+                                  &tlb_debugfs_fops);
+       if (unlikely(!utlb)) {
+               debugfs_remove(itlb);
+               return -ENOMEM;
+       }
+
+       if (IS_ERR(utlb)) {
+               debugfs_remove(itlb);
+               return PTR_ERR(utlb);
+       }
+
+       return 0;
+}
+module_init(tlb_debugfs_init);
+
+MODULE_LICENSE("GPL v2");