/*
 * Based on linux/arch/mips/txx9/rbtx4938/setup.c,
 *          and RBTX49xx patch from CELF patch archive.
 *
 * 2003-2005 (c) MontaVista Software, Inc.
 * (C) Copyright TOSHIBA CORPORATION 2000-2001, 2004-2007
 *
 * 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/kernel.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/string.h>
#include <linux/export.h>
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/err.h>
#include <linux/gpio/driver.h>
#include <linux/platform_device.h>
#include <linux/platform_data/txx9/ndfmc.h>
#include <linux/serial_core.h>
#include <linux/mtd/physmap.h>
#include <linux/leds.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <asm/bootinfo.h>
#include <asm/idle.h>
#include <asm/time.h>
#include <asm/reboot.h>
#include <asm/r4kcache.h>
#include <asm/setup.h>
#include <asm/txx9/generic.h>
#include <asm/txx9/pci.h>
#include <asm/txx9tmr.h>
#include <asm/txx9/dmac.h>
#ifdef CONFIG_CPU_TX49XX
#include <asm/txx9/tx4938.h>
#endif

/* EBUSC settings of TX4927, etc. */
struct resource txx9_ce_res[8];
static char txx9_ce_res_name[8][4];     /* "CEn" */

/* pcode, internal register */
unsigned int txx9_pcode;
char txx9_pcode_str[8];
static struct resource txx9_reg_res = {
        .name = txx9_pcode_str,
        .flags = IORESOURCE_MEM,
};
void __init
txx9_reg_res_init(unsigned int pcode, unsigned long base, unsigned long size)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(txx9_ce_res); i++) {
                sprintf(txx9_ce_res_name[i], "CE%d", i);
                txx9_ce_res[i].flags = IORESOURCE_MEM;
                txx9_ce_res[i].name = txx9_ce_res_name[i];
        }

        txx9_pcode = pcode;
        sprintf(txx9_pcode_str, "TX%x", pcode);
        if (base) {
                txx9_reg_res.start = base & 0xfffffffffULL;
                txx9_reg_res.end = (base & 0xfffffffffULL) + (size - 1);
                request_resource(&iomem_resource, &txx9_reg_res);
        }
}

/* clocks */
unsigned int txx9_master_clock;
unsigned int txx9_cpu_clock;
unsigned int txx9_gbus_clock;

int txx9_ccfg_toeon __initdata = 1;

#define BOARD_VEC(board)        extern struct txx9_board_vec board;
#include <asm/txx9/boards.h>
#undef BOARD_VEC

struct txx9_board_vec *txx9_board_vec __initdata;
static char txx9_system_type[32];

static struct txx9_board_vec *board_vecs[] __initdata = {
#define BOARD_VEC(board)        &board,
#include <asm/txx9/boards.h>
#undef BOARD_VEC
};

static struct txx9_board_vec *__init find_board_byname(const char *name)
{
        int i;

        /* search board_vecs table */
        for (i = 0; i < ARRAY_SIZE(board_vecs); i++) {
                if (strstr(board_vecs[i]->system, name))
                        return board_vecs[i];
        }
        return NULL;
}

static void __init prom_init_cmdline(void)
{
        int argc;
        int *argv32;
        int i;                  /* Always ignore the "-c" at argv[0] */

        if (fw_arg0 >= CKSEG0 || fw_arg1 < CKSEG0) {
                /*
                 * argc is not a valid number, or argv32 is not a valid
                 * pointer
                 */
                argc = 0;
                argv32 = NULL;
        } else {
                argc = (int)fw_arg0;
                argv32 = (int *)fw_arg1;
        }

        arcs_cmdline[0] = '\0';

        for (i = 1; i < argc; i++) {
                char *str = (char *)(long)argv32[i];
                if (i != 1)
                        strcat(arcs_cmdline, " ");
                if (strchr(str, ' ')) {
                        strcat(arcs_cmdline, "\"");
                        strcat(arcs_cmdline, str);
                        strcat(arcs_cmdline, "\"");
                } else
                        strcat(arcs_cmdline, str);
        }
}

static int txx9_ic_disable __initdata;
static int txx9_dc_disable __initdata;

#if defined(CONFIG_CPU_TX49XX)
/* flush all cache on very early stage (before 4k_cache_init) */
static void __init early_flush_dcache(void)
{
        unsigned int conf = read_c0_config();
        unsigned int dc_size = 1 << (12 + ((conf & CONF_DC) >> 6));
        unsigned int linesz = 32;
        unsigned long addr, end;

        end = INDEX_BASE + dc_size / 4;
        /* 4way, waybit=0 */
        for (addr = INDEX_BASE; addr < end; addr += linesz) {
                cache_op(Index_Writeback_Inv_D, addr | 0);
                cache_op(Index_Writeback_Inv_D, addr | 1);
                cache_op(Index_Writeback_Inv_D, addr | 2);
                cache_op(Index_Writeback_Inv_D, addr | 3);
        }
}

static void __init txx9_cache_fixup(void)
{
        unsigned int conf;

        conf = read_c0_config();
        /* flush and disable */
        if (txx9_ic_disable) {
                conf |= TX49_CONF_IC;
                write_c0_config(conf);
        }
        if (txx9_dc_disable) {
                early_flush_dcache();
                conf |= TX49_CONF_DC;
                write_c0_config(conf);
        }

        /* enable cache */
        conf = read_c0_config();
        if (!txx9_ic_disable)
                conf &= ~TX49_CONF_IC;
        if (!txx9_dc_disable)
                conf &= ~TX49_CONF_DC;
        write_c0_config(conf);

        if (conf & TX49_CONF_IC)
                pr_info("TX49XX I-Cache disabled.\n");
        if (conf & TX49_CONF_DC)
                pr_info("TX49XX D-Cache disabled.\n");
}
#else
static inline void txx9_cache_fixup(void)
{
}
#endif

static void __init preprocess_cmdline(void)
{
        static char cmdline[COMMAND_LINE_SIZE] __initdata;
        char *s;

        strscpy(cmdline, arcs_cmdline);
        s = cmdline;
        arcs_cmdline[0] = '\0';
        while (s && *s) {
                char *str = strsep(&s, " ");
                if (strncmp(str, "board=", 6) == 0) {
                        txx9_board_vec = find_board_byname(str + 6);
                        continue;
                } else if (strncmp(str, "masterclk=", 10) == 0) {
                        unsigned int val;
                        if (kstrtouint(str + 10, 10, &val) == 0)
                                txx9_master_clock = val;
                        continue;
                } else if (strcmp(str, "icdisable") == 0) {
                        txx9_ic_disable = 1;
                        continue;
                } else if (strcmp(str, "dcdisable") == 0) {
                        txx9_dc_disable = 1;
                        continue;
                } else if (strcmp(str, "toeoff") == 0) {
                        txx9_ccfg_toeon = 0;
                        continue;
                } else if (strcmp(str, "toeon") == 0) {
                        txx9_ccfg_toeon = 1;
                        continue;
                }
                if (arcs_cmdline[0])
                        strcat(arcs_cmdline, " ");
                strcat(arcs_cmdline, str);
        }

        txx9_cache_fixup();
}

static void __init select_board(void)
{
        const char *envstr;

        /* first, determine by "board=" argument in preprocess_cmdline() */
        if (txx9_board_vec)
                return;
        /* next, determine by "board" envvar */
        envstr = prom_getenv("board");
        if (envstr) {
                txx9_board_vec = find_board_byname(envstr);
                if (txx9_board_vec)
                        return;
        }

        /* select "default" board */
#ifdef CONFIG_CPU_TX49XX
        switch (TX4938_REV_PCODE()) {
#ifdef CONFIG_TOSHIBA_RBTX4927
        case 0x4927:
                txx9_board_vec = &rbtx4927_vec;
                break;
        case 0x4937:
                txx9_board_vec = &rbtx4937_vec;
                break;
#endif
        }
#endif
}

void __init prom_init(void)
{
        prom_init_cmdline();
        preprocess_cmdline();
        select_board();

        strscpy(txx9_system_type, txx9_board_vec->system);

        txx9_board_vec->prom_init();
}

const char *get_system_type(void)
{
        return txx9_system_type;
}

const char *__init prom_getenv(const char *name)
{
        const s32 *str;

        if (fw_arg2 < CKSEG0)
                return NULL;

        str = (const s32 *)fw_arg2;
        /* YAMON style ("name", "value" pairs) */
        while (str[0] && str[1]) {
                if (!strcmp((const char *)(unsigned long)str[0], name))
                        return (const char *)(unsigned long)str[1];
                str += 2;
        }
        return NULL;
}

static void __noreturn txx9_machine_halt(void)
{
        local_irq_disable();
        clear_c0_status(ST0_IM);
        while (1) {
                if (cpu_wait) {
                        (*cpu_wait)();
                        if (cpu_has_counter) {
                                /*
                                 * Clear counter interrupt while it
                                 * breaks WAIT instruction even if
                                 * masked.
                                 */
                                write_c0_compare(0);
                        }
                }
        }
}

/* Watchdog support */
void __init txx9_wdt_init(unsigned long base)
{
        struct resource res = {
                .start  = base,
                .end    = base + 0x100 - 1,
                .flags  = IORESOURCE_MEM,
        };
        platform_device_register_simple("txx9wdt", -1, &res, 1);
}

void txx9_wdt_now(unsigned long base)
{
        struct txx9_tmr_reg __iomem *tmrptr =
                ioremap(base, sizeof(struct txx9_tmr_reg));
        /* disable watch dog timer */
        __raw_writel(TXx9_TMWTMR_WDIS | TXx9_TMWTMR_TWC, &tmrptr->wtmr);
        __raw_writel(0, &tmrptr->tcr);
        /* kick watchdog */
        __raw_writel(TXx9_TMWTMR_TWIE, &tmrptr->wtmr);
        __raw_writel(1, &tmrptr->cpra); /* immediate */
        __raw_writel(TXx9_TMTCR_TCE | TXx9_TMTCR_CCDE | TXx9_TMTCR_TMODE_WDOG,
                     &tmrptr->tcr);
}

/* SPI support */
void __init txx9_spi_init(int busid, unsigned long base, int irq)
{
        struct resource res[] = {
                {
                        .start  = base,
                        .end    = base + 0x20 - 1,
                        .flags  = IORESOURCE_MEM,
                }, {
                        .start  = irq,
                        .flags  = IORESOURCE_IRQ,
                },
        };
        platform_device_register_simple("spi_txx9", busid,
                                        res, ARRAY_SIZE(res));
}

void __init txx9_ethaddr_init(unsigned int id, unsigned char *ethaddr)
{
        struct platform_device *pdev =
                platform_device_alloc("tc35815-mac", id);
        if (!pdev ||
            platform_device_add_data(pdev, ethaddr, 6) ||
            platform_device_add(pdev))
                platform_device_put(pdev);
}

void __init txx9_sio_init(unsigned long baseaddr, int irq,
                          unsigned int line, unsigned int sclk, int nocts)
{
#ifdef CONFIG_SERIAL_TXX9
        struct uart_port req;

        memset(&req, 0, sizeof(req));
        req.line = line;
        req.iotype = UPIO_MEM;
        req.membase = ioremap(baseaddr, 0x24);
        req.mapbase = baseaddr;
        req.irq = irq;
        if (!nocts)
                req.flags |= UPF_BUGGY_UART /*HAVE_CTS_LINE*/;
        if (sclk) {
                req.flags |= UPF_MAGIC_MULTIPLIER /*USE_SCLK*/;
                req.uartclk = sclk;
        } else
                req.uartclk = TXX9_IMCLK;
        early_serial_txx9_setup(&req);
#endif /* CONFIG_SERIAL_TXX9 */
}

#ifdef CONFIG_EARLY_PRINTK
static void null_prom_putchar(char c)
{
}
void (*txx9_prom_putchar)(char c) = null_prom_putchar;

void prom_putchar(char c)
{
        txx9_prom_putchar(c);
}

static void __iomem *early_txx9_sio_port;

static void early_txx9_sio_putchar(char c)
{
#define TXX9_SICISR     0x0c
#define TXX9_SITFIFO    0x1c
#define TXX9_SICISR_TXALS       0x00000002
        while (!(__raw_readl(early_txx9_sio_port + TXX9_SICISR) &
                 TXX9_SICISR_TXALS))
                ;
        __raw_writel(c, early_txx9_sio_port + TXX9_SITFIFO);
}

void __init txx9_sio_putchar_init(unsigned long baseaddr)
{
        early_txx9_sio_port = ioremap(baseaddr, 0x24);
        txx9_prom_putchar = early_txx9_sio_putchar;
}
#endif /* CONFIG_EARLY_PRINTK */

/* wrappers */
void __init plat_mem_setup(void)
{
        ioport_resource.start = 0;
        ioport_resource.end = ~0UL;     /* no limit */
        iomem_resource.start = 0;
        iomem_resource.end = ~0UL;      /* no limit */

        /* fallback restart/halt routines */
        _machine_restart = (void (*)(char *))txx9_machine_halt;
        _machine_halt = txx9_machine_halt;
        pm_power_off = txx9_machine_halt;

#ifdef CONFIG_PCI
        pcibios_plat_setup = txx9_pcibios_setup;
#endif
        txx9_board_vec->mem_setup();
}

void __init arch_init_irq(void)
{
        txx9_board_vec->irq_setup();
}

void __init plat_time_init(void)
{
#ifdef CONFIG_CPU_TX49XX
        mips_hpt_frequency = txx9_cpu_clock / 2;
#endif
        txx9_board_vec->time_init();
}

static void txx9_clk_init(void)
{
        struct clk_hw *hw;
        int error;

        hw = clk_hw_register_fixed_rate(NULL, "gbus", NULL, 0, txx9_gbus_clock);
        if (IS_ERR(hw)) {
                error = PTR_ERR(hw);
                goto fail;
        }

        hw = clk_hw_register_fixed_factor(NULL, "imbus", "gbus", 0, 1, 2);
        error = clk_hw_register_clkdev(hw, "imbus_clk", NULL);
        if (error)
                goto fail;

#ifdef CONFIG_CPU_TX49XX
        if (TX4938_REV_PCODE() == 0x4938) {
                hw = clk_hw_register_fixed_factor(NULL, "spi", "gbus", 0, 1, 4);
                error = clk_hw_register_clkdev(hw, "spi-baseclk", NULL);
                if (error)
                        goto fail;
        }
#endif

        return;

fail:
        pr_err("Failed to register clocks: %d\n", error);
}

static int __init _txx9_arch_init(void)
{
        txx9_clk_init();

        if (txx9_board_vec->arch_init)
                txx9_board_vec->arch_init();
        return 0;
}
arch_initcall(_txx9_arch_init);

static int __init _txx9_device_init(void)
{
        if (txx9_board_vec->device_init)
                txx9_board_vec->device_init();
        return 0;
}
device_initcall(_txx9_device_init);

int (*txx9_irq_dispatch)(int pending);
asmlinkage void plat_irq_dispatch(void)
{
        int pending = read_c0_status() & read_c0_cause() & ST0_IM;
        int irq = txx9_irq_dispatch(pending);

        if (likely(irq >= 0))
                do_IRQ(irq);
        else
                spurious_interrupt();
}

/* see include/asm-mips/mach-tx39xx/mangle-port.h, for example. */
#ifdef NEEDS_TXX9_SWIZZLE_ADDR_B
static unsigned long __swizzle_addr_none(unsigned long port)
{
        return port;
}
unsigned long (*__swizzle_addr_b)(unsigned long port) = __swizzle_addr_none;
EXPORT_SYMBOL(__swizzle_addr_b);
#endif

void __init txx9_physmap_flash_init(int no, unsigned long addr,
                                    unsigned long size,
                                    const struct physmap_flash_data *pdata)
{
#if IS_ENABLED(CONFIG_MTD_PHYSMAP)
        struct resource res = {
                .start = addr,
                .end = addr + size - 1,
                .flags = IORESOURCE_MEM,
        };
        struct platform_device *pdev;
        static struct mtd_partition parts[2];
        struct physmap_flash_data pdata_part;

        /* If this area contained boot area, make separate partition */
        if (pdata->nr_parts == 0 && !pdata->parts &&
            addr < 0x1fc00000 && addr + size > 0x1fc00000 &&
            !parts[0].name) {
                parts[0].name = "boot";
                parts[0].offset = 0x1fc00000 - addr;
                parts[0].size = addr + size - 0x1fc00000;
                parts[1].name = "user";
                parts[1].offset = 0;
                parts[1].size = 0x1fc00000 - addr;
                pdata_part = *pdata;
                pdata_part.nr_parts = ARRAY_SIZE(parts);
                pdata_part.parts = parts;
                pdata = &pdata_part;
        }

        pdev = platform_device_alloc("physmap-flash", no);
        if (!pdev ||
            platform_device_add_resources(pdev, &res, 1) ||
            platform_device_add_data(pdev, pdata, sizeof(*pdata)) ||
            platform_device_add(pdev))
                platform_device_put(pdev);
#endif
}

void __init txx9_ndfmc_init(unsigned long baseaddr,
                            const struct txx9ndfmc_platform_data *pdata)
{
#if IS_ENABLED(CONFIG_MTD_NAND_TXX9NDFMC)
        struct resource res = {
                .start = baseaddr,
                .end = baseaddr + 0x1000 - 1,
                .flags = IORESOURCE_MEM,
        };
        struct platform_device *pdev = platform_device_alloc("txx9ndfmc", -1);

        if (!pdev ||
            platform_device_add_resources(pdev, &res, 1) ||
            platform_device_add_data(pdev, pdata, sizeof(*pdata)) ||
            platform_device_add(pdev))
                platform_device_put(pdev);
#endif
}

#if IS_ENABLED(CONFIG_LEDS_GPIO)
static DEFINE_SPINLOCK(txx9_iocled_lock);

#define TXX9_IOCLED_MAXLEDS 8

struct txx9_iocled_data {
        struct gpio_chip chip;
        u8 cur_val;
        void __iomem *mmioaddr;
        struct gpio_led_platform_data pdata;
        struct gpio_led leds[TXX9_IOCLED_MAXLEDS];
        char names[TXX9_IOCLED_MAXLEDS][32];
};

static int txx9_iocled_get(struct gpio_chip *chip, unsigned int offset)
{
        struct txx9_iocled_data *data = gpiochip_get_data(chip);
        return !!(data->cur_val & (1 << offset));
}

static int txx9_iocled_set(struct gpio_chip *chip, unsigned int offset,
                           int value)
{
        struct txx9_iocled_data *data = gpiochip_get_data(chip);
        unsigned long flags;
        spin_lock_irqsave(&txx9_iocled_lock, flags);
        if (value)
                data->cur_val |= 1 << offset;
        else
                data->cur_val &= ~(1 << offset);
        writeb(data->cur_val, data->mmioaddr);
        mmiowb();
        spin_unlock_irqrestore(&txx9_iocled_lock, flags);

        return 0;
}

static int txx9_iocled_dir_in(struct gpio_chip *chip, unsigned int offset)
{
        return 0;
}

static int txx9_iocled_dir_out(struct gpio_chip *chip, unsigned int offset,
                               int value)
{
        txx9_iocled_set(chip, offset, value);
        return 0;
}

void __init txx9_iocled_init(unsigned long baseaddr,
                             int basenum, unsigned int num, int lowactive,
                             const char *color, char **deftriggers)
{
        struct txx9_iocled_data *iocled;
        struct platform_device *pdev;
        int i;
        static char *default_triggers[] __initdata = {
                "heartbeat",
                "disk-activity",
                "nand-disk",
                NULL,
        };

        if (!deftriggers)
                deftriggers = default_triggers;
        iocled = kzalloc_obj(*iocled);
        if (!iocled)
                return;
        iocled->mmioaddr = ioremap(baseaddr, 1);
        if (!iocled->mmioaddr)
                goto out_free;
        iocled->chip.get = txx9_iocled_get;
        iocled->chip.set = txx9_iocled_set;
        iocled->chip.direction_input = txx9_iocled_dir_in;
        iocled->chip.direction_output = txx9_iocled_dir_out;
        iocled->chip.label = "iocled";
        iocled->chip.base = basenum;
        iocled->chip.ngpio = num;
        if (gpiochip_add_data(&iocled->chip, iocled))
                goto out_unmap;
        if (basenum < 0)
                basenum = iocled->chip.base;

        pdev = platform_device_alloc("leds-gpio", basenum);
        if (!pdev)
                goto out_gpio;
        iocled->pdata.num_leds = num;
        iocled->pdata.leds = iocled->leds;
        for (i = 0; i < num; i++) {
                struct gpio_led *led = &iocled->leds[i];
                snprintf(iocled->names[i], sizeof(iocled->names[i]),
                         "iocled:%s:%u", color, i);
                led->name = iocled->names[i];
                led->gpio = basenum + i;
                led->active_low = lowactive;
                if (deftriggers && *deftriggers)
                        led->default_trigger = *deftriggers++;
        }
        pdev->dev.platform_data = &iocled->pdata;
        if (platform_device_add(pdev))
                goto out_pdev;
        return;

out_pdev:
        platform_device_put(pdev);
out_gpio:
        gpiochip_remove(&iocled->chip);
out_unmap:
        iounmap(iocled->mmioaddr);
out_free:
        kfree(iocled);
}
#else /* CONFIG_LEDS_GPIO */
void __init txx9_iocled_init(unsigned long baseaddr,
                             int basenum, unsigned int num, int lowactive,
                             const char *color, char **deftriggers)
{
}
#endif /* CONFIG_LEDS_GPIO */

void __init txx9_dmac_init(int id, unsigned long baseaddr, int irq,
                           const struct txx9dmac_platform_data *pdata)
{
#if IS_ENABLED(CONFIG_TXX9_DMAC)
        struct resource res[] = {
                {
                        .start = baseaddr,
                        .end = baseaddr + 0x800 - 1,
                        .flags = IORESOURCE_MEM,
#ifndef CONFIG_MACH_TX49XX
                }, {
                        .start = irq,
                        .flags = IORESOURCE_IRQ,
#endif
                }
        };
#ifdef CONFIG_MACH_TX49XX
        struct resource chan_res[] = {
                {
                        .flags = IORESOURCE_IRQ,
                }
        };
#endif
        struct platform_device *pdev = platform_device_alloc("txx9dmac", id);
        struct txx9dmac_chan_platform_data cpdata;
        int i;

        if (!pdev ||
            platform_device_add_resources(pdev, res, ARRAY_SIZE(res)) ||
            platform_device_add_data(pdev, pdata, sizeof(*pdata)) ||
            platform_device_add(pdev)) {
                platform_device_put(pdev);
                return;
        }
        memset(&cpdata, 0, sizeof(cpdata));
        cpdata.dmac_dev = pdev;
        for (i = 0; i < TXX9_DMA_MAX_NR_CHANNELS; i++) {
#ifdef CONFIG_MACH_TX49XX
                chan_res[0].start = irq + i;
#endif
                pdev = platform_device_alloc("txx9dmac-chan",
                                             id * TXX9_DMA_MAX_NR_CHANNELS + i);
                if (!pdev ||
#ifdef CONFIG_MACH_TX49XX
                    platform_device_add_resources(pdev, chan_res,
                                                  ARRAY_SIZE(chan_res)) ||
#endif
                    platform_device_add_data(pdev, &cpdata, sizeof(cpdata)) ||
                    platform_device_add(pdev))
                        platform_device_put(pdev);
        }
#endif
}

void __init txx9_aclc_init(unsigned long baseaddr, int irq,
                           unsigned int dmac_id,
                           unsigned int dma_chan_out,
                           unsigned int dma_chan_in)
{
}

static const struct bus_type txx9_sramc_subsys = {
        .name = "txx9_sram",
        .dev_name = "txx9_sram",
};

struct txx9_sramc_dev {
        struct device dev;
        struct bin_attribute bindata_attr;
        void __iomem *base;
};

static ssize_t txx9_sram_read(struct file *filp, struct kobject *kobj,
                              const struct bin_attribute *bin_attr,
                              char *buf, loff_t pos, size_t size)
{
        struct txx9_sramc_dev *dev = bin_attr->private;
        size_t ramsize = bin_attr->size;

        if (pos >= ramsize)
                return 0;
        if (pos + size > ramsize)
                size = ramsize - pos;
        memcpy_fromio(buf, dev->base + pos, size);
        return size;
}

static ssize_t txx9_sram_write(struct file *filp, struct kobject *kobj,
                               const struct bin_attribute *bin_attr,
                               char *buf, loff_t pos, size_t size)
{
        struct txx9_sramc_dev *dev = bin_attr->private;
        size_t ramsize = bin_attr->size;

        if (pos >= ramsize)
                return 0;
        if (pos + size > ramsize)
                size = ramsize - pos;
        memcpy_toio(dev->base + pos, buf, size);
        return size;
}

static void txx9_device_release(struct device *dev)
{
        struct txx9_sramc_dev *tdev;

        tdev = container_of(dev, struct txx9_sramc_dev, dev);
        kfree(tdev);
}

void __init txx9_sramc_init(struct resource *r)
{
        struct txx9_sramc_dev *dev;
        size_t size;
        int err;

        err = subsys_system_register(&txx9_sramc_subsys, NULL);
        if (err)
                return;
        dev = kzalloc_obj(*dev);
        if (!dev)
                return;
        size = resource_size(r);
        dev->base = ioremap(r->start, size);
        if (!dev->base) {
                kfree(dev);
                return;
        }
        dev->dev.release = &txx9_device_release;
        dev->dev.bus = &txx9_sramc_subsys;
        sysfs_bin_attr_init(&dev->bindata_attr);
        dev->bindata_attr.attr.name = "bindata";
        dev->bindata_attr.attr.mode = S_IRUSR | S_IWUSR;
        dev->bindata_attr.read = txx9_sram_read;
        dev->bindata_attr.write = txx9_sram_write;
        dev->bindata_attr.size = size;
        dev->bindata_attr.private = dev;
        err = device_register(&dev->dev);
        if (err)
                goto exit_put;
        err = sysfs_create_bin_file(&dev->dev.kobj, &dev->bindata_attr);
        if (err) {
                iounmap(dev->base);
                device_unregister(&dev->dev);
        }
        return;
exit_put:
        iounmap(dev->base);
        put_device(&dev->dev);
}