/*
 * 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)
{
        debugfs_create_file("itlb", S_IRUSR, arch_debugfs_dir,
                            (void *)TLB_TYPE_ITLB, &tlb_debugfs_fops);
        debugfs_create_file("utlb", S_IRUSR, arch_debugfs_dir,
                            (void *)TLB_TYPE_UTLB, &tlb_debugfs_fops);
        return 0;
}
module_init(tlb_debugfs_init);

MODULE_LICENSE("GPL v2");