Linux 5.7.7

[linux/fpc-iii.git] / arch / arm / mach-sa1100 / assabet.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * linux/arch/arm/mach-sa1100/assabet.c
 *
 * Author: Nicolas Pitre
 *
 * This file contains all Assabet-specific tweaks.
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/gpio/gpio-reg.h>
#include <linux/gpio/machine.h>
#include <linux/gpio_keys.h>
#include <linux/ioport.h>
#include <linux/platform_data/sa11x0-serial.h>
#include <linux/regulator/fixed.h>
#include <linux/regulator/machine.h>
#include <linux/serial_core.h>
#include <linux/platform_device.h>
#include <linux/mfd/ucb1x00.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/delay.h>
#include <linux/mm.h>
#include <linux/leds.h>
#include <linux/slab.h>

#include <video/sa1100fb.h>

#include <mach/hardware.h>
#include <asm/mach-types.h>
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/pgtable-hwdef.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>

#include <asm/mach/arch.h>
#include <asm/mach/flash.h>
#include <linux/platform_data/irda-sa11x0.h>
#include <asm/mach/map.h>
#include <mach/assabet.h>
#include <linux/platform_data/mfd-mcp-sa11x0.h>
#include <mach/irqs.h>

#include "generic.h"

#define ASSABET_BCR_DB1110 \
        (ASSABET_BCR_SPK_OFF    | \
         ASSABET_BCR_LED_GREEN  | ASSABET_BCR_LED_RED   | \
         ASSABET_BCR_RS232EN    | ASSABET_BCR_LCD_12RGB | \
         ASSABET_BCR_IRDA_MD0)

#define ASSABET_BCR_DB1111 \
        (ASSABET_BCR_SPK_OFF    | \
         ASSABET_BCR_LED_GREEN  | ASSABET_BCR_LED_RED   | \
         ASSABET_BCR_RS232EN    | ASSABET_BCR_LCD_12RGB | \
         ASSABET_BCR_CF_BUS_OFF | ASSABET_BCR_STEREO_LB | \
         ASSABET_BCR_IRDA_MD0   | ASSABET_BCR_CF_RST)

unsigned long SCR_value = ASSABET_SCR_INIT;
EXPORT_SYMBOL(SCR_value);

static struct gpio_chip *assabet_bcr_gc;

static const char *assabet_names[] = {
        "cf_pwr", "cf_gfx_reset", "nsoft_reset", "irda_fsel",
        "irda_md0", "irda_md1", "stereo_loopback", "ncf_bus_on",
        "audio_pwr_on", "light_pwr_on", "lcd16data", "lcd_pwr_on",
        "rs232_on", "nred_led", "ngreen_led", "vib_on",
        "com_dtr", "com_rts", "radio_wake_mod", "i2c_enab",
        "tvir_enab", "qmute", "radio_pwr_on", "spkr_off",
        "rs232_valid", "com_dcd", "com_cts", "com_dsr",
        "radio_cts", "radio_dsr", "radio_dcd", "radio_ri",
};

/* The old deprecated interface */
void ASSABET_BCR_frob(unsigned int mask, unsigned int val)
{
        unsigned long m = mask, v = val;

        assabet_bcr_gc->set_multiple(assabet_bcr_gc, &m, &v);
}
EXPORT_SYMBOL(ASSABET_BCR_frob);

static int __init assabet_init_gpio(void __iomem *reg, u32 def_val)
{
        struct gpio_chip *gc;

        writel_relaxed(def_val, reg);

        gc = gpio_reg_init(NULL, reg, -1, 32, "assabet", 0xff000000, def_val,
                           assabet_names, NULL, NULL);

        if (IS_ERR(gc))
                return PTR_ERR(gc);

        assabet_bcr_gc = gc;

        return gc->base;
}

/*
 * The codec reset goes to three devices, so we need to release
 * the rest when any one of these requests it.  However, that
 * causes the ADV7171 to consume around 100mA - more than half
 * the LCD-blanked power.
 *
 * With the ADV7171, LCD and backlight enabled, we go over
 * budget on the MAX846 Li-Ion charger, and if no Li-Ion battery
 * is connected, the Assabet crashes.
 */
#define RST_UCB1X00 (1 << 0)
#define RST_UDA1341 (1 << 1)
#define RST_ADV7171 (1 << 2)

#define SDA GPIO_GPIO(15)
#define SCK GPIO_GPIO(18)
#define MOD GPIO_GPIO(17)

static void adv7171_start(void)
{
        GPSR = SCK;
        udelay(1);
        GPSR = SDA;
        udelay(2);
        GPCR = SDA;
}

static void adv7171_stop(void)
{
        GPSR = SCK;
        udelay(2);
        GPSR = SDA;
        udelay(1);
}

static void adv7171_send(unsigned byte)
{
        unsigned i;

        for (i = 0; i < 8; i++, byte <<= 1) {
                GPCR = SCK;
                udelay(1);
                if (byte & 0x80)
                        GPSR = SDA;
                else
                        GPCR = SDA;
                udelay(1);
                GPSR = SCK;
                udelay(1);
        }
        GPCR = SCK;
        udelay(1);
        GPSR = SDA;
        udelay(1);
        GPDR &= ~SDA;
        GPSR = SCK;
        udelay(1);
        if (GPLR & SDA)
                printk(KERN_WARNING "No ACK from ADV7171\n");
        udelay(1);
        GPCR = SCK | SDA;
        udelay(1);
        GPDR |= SDA;
        udelay(1);
}

static void adv7171_write(unsigned reg, unsigned val)
{
        unsigned gpdr = GPDR;
        unsigned gplr = GPLR;

        ASSABET_BCR_frob(ASSABET_BCR_AUDIO_ON, ASSABET_BCR_AUDIO_ON);
        udelay(100);

        GPCR = SDA | SCK | MOD; /* clear L3 mode to ensure UDA1341 doesn't respond */
        GPDR = (GPDR | SCK | MOD) & ~SDA;
        udelay(10);
        if (!(GPLR & SDA))
                printk(KERN_WARNING "Something dragging SDA down?\n");
        GPDR |= SDA;

        adv7171_start();
        adv7171_send(0x54);
        adv7171_send(reg);
        adv7171_send(val);
        adv7171_stop();

        /* Restore GPIO state for L3 bus */
        GPSR = gplr & (SDA | SCK | MOD);
        GPCR = (~gplr) & (SDA | SCK | MOD);
        GPDR = gpdr;
}

static void adv7171_sleep(void)
{
        /* Put the ADV7171 into sleep mode */
        adv7171_write(0x04, 0x40);
}

static unsigned codec_nreset;

static void assabet_codec_reset(unsigned mask, int set)
{
        unsigned long flags;
        bool old;

        local_irq_save(flags);
        old = !codec_nreset;
        if (set)
                codec_nreset &= ~mask;
        else
                codec_nreset |= mask;

        if (old != !codec_nreset) {
                if (codec_nreset) {
                        ASSABET_BCR_set(ASSABET_BCR_NCODEC_RST);
                        adv7171_sleep();
                } else {
                        ASSABET_BCR_clear(ASSABET_BCR_NCODEC_RST);
                }
        }
        local_irq_restore(flags);
}

static void assabet_ucb1x00_reset(enum ucb1x00_reset state)
{
        int set = state == UCB_RST_REMOVE || state == UCB_RST_SUSPEND ||
                state == UCB_RST_PROBE_FAIL;
        assabet_codec_reset(RST_UCB1X00, set);
}

void assabet_uda1341_reset(int set)
{
        assabet_codec_reset(RST_UDA1341, set);
}
EXPORT_SYMBOL(assabet_uda1341_reset);


/*
 * Assabet flash support code.
 */

#ifdef ASSABET_REV_4
/*
 * Phase 4 Assabet has two 28F160B3 flash parts in bank 0:
 */
static struct mtd_partition assabet_partitions[] = {
        {
                .name           = "bootloader",
                .size           = 0x00020000,
                .offset         = 0,
                .mask_flags     = MTD_WRITEABLE,
        }, {
                .name           = "bootloader params",
                .size           = 0x00020000,
                .offset         = MTDPART_OFS_APPEND,
                .mask_flags     = MTD_WRITEABLE,
        }, {
                .name           = "jffs",
                .size           = MTDPART_SIZ_FULL,
                .offset         = MTDPART_OFS_APPEND,
        }
};
#else
/*
 * Phase 5 Assabet has two 28F128J3A flash parts in bank 0:
 */
static struct mtd_partition assabet_partitions[] = {
        {
                .name           = "bootloader",
                .size           = 0x00040000,
                .offset         = 0,
                .mask_flags     = MTD_WRITEABLE,
        }, {
                .name           = "bootloader params",
                .size           = 0x00040000,
                .offset         = MTDPART_OFS_APPEND,
                .mask_flags     = MTD_WRITEABLE,
        }, {
                .name           = "jffs",
                .size           = MTDPART_SIZ_FULL,
                .offset         = MTDPART_OFS_APPEND,
        }
};
#endif

static struct flash_platform_data assabet_flash_data = {
        .map_name       = "cfi_probe",
        .parts          = assabet_partitions,
        .nr_parts       = ARRAY_SIZE(assabet_partitions),
};

static struct resource assabet_flash_resources[] = {
        DEFINE_RES_MEM(SA1100_CS0_PHYS, SZ_32M),
        DEFINE_RES_MEM(SA1100_CS1_PHYS, SZ_32M),
};


/*
 * Assabet IrDA support code.
 */

static int assabet_irda_set_power(struct device *dev, unsigned int state)
{
        static unsigned int bcr_state[4] = {
                ASSABET_BCR_IRDA_MD0,
                ASSABET_BCR_IRDA_MD1|ASSABET_BCR_IRDA_MD0,
                ASSABET_BCR_IRDA_MD1,
                0
        };

        if (state < 4)
                ASSABET_BCR_frob(ASSABET_BCR_IRDA_MD1 | ASSABET_BCR_IRDA_MD0,
                                 bcr_state[state]);
        return 0;
}

static void assabet_irda_set_speed(struct device *dev, unsigned int speed)
{
        if (speed < 4000000)
                ASSABET_BCR_clear(ASSABET_BCR_IRDA_FSEL);
        else
                ASSABET_BCR_set(ASSABET_BCR_IRDA_FSEL);
}

static struct irda_platform_data assabet_irda_data = {
        .set_power      = assabet_irda_set_power,
        .set_speed      = assabet_irda_set_speed,
};

static struct ucb1x00_plat_data assabet_ucb1x00_data = {
        .reset          = assabet_ucb1x00_reset,
        .gpio_base      = -1,
        .can_wakeup     = 1,
};

static struct mcp_plat_data assabet_mcp_data = {
        .mccr0          = MCCR0_ADM,
        .sclk_rate      = 11981000,
        .codec_pdata    = &assabet_ucb1x00_data,
};

static void assabet_lcd_set_visual(u32 visual)
{
        u_int is_true_color = visual == FB_VISUAL_TRUECOLOR;

        if (machine_is_assabet()) {
#if 1           // phase 4 or newer Assabet's
                if (is_true_color)
                        ASSABET_BCR_set(ASSABET_BCR_LCD_12RGB);
                else
                        ASSABET_BCR_clear(ASSABET_BCR_LCD_12RGB);
#else
                // older Assabet's
                if (is_true_color)
                        ASSABET_BCR_clear(ASSABET_BCR_LCD_12RGB);
                else
                        ASSABET_BCR_set(ASSABET_BCR_LCD_12RGB);
#endif
        }
}

#ifndef ASSABET_PAL_VIDEO
static void assabet_lcd_backlight_power(int on)
{
        if (on)
                ASSABET_BCR_set(ASSABET_BCR_LIGHT_ON);
        else
                ASSABET_BCR_clear(ASSABET_BCR_LIGHT_ON);
}

/*
 * Turn on/off the backlight.  When turning the backlight on, we wait
 * 500us after turning it on so we don't cause the supplies to droop
 * when we enable the LCD controller (and cause a hard reset.)
 */
static void assabet_lcd_power(int on)
{
        if (on) {
                ASSABET_BCR_set(ASSABET_BCR_LCD_ON);
                udelay(500);
        } else
                ASSABET_BCR_clear(ASSABET_BCR_LCD_ON);
}

/*
 * The assabet uses a sharp LQ039Q2DS54 LCD module.  It is actually
 * takes an RGB666 signal, but we provide it with an RGB565 signal
 * instead (def_rgb_16).
 */
static struct sa1100fb_mach_info lq039q2ds54_info = {
        .pixclock       = 171521,       .bpp            = 16,
        .xres           = 320,          .yres           = 240,

        .hsync_len      = 5,            .vsync_len      = 1,
        .left_margin    = 61,           .upper_margin   = 3,
        .right_margin   = 9,            .lower_margin   = 0,

        .sync           = FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,

        .lccr0          = LCCR0_Color | LCCR0_Sngl | LCCR0_Act,
        .lccr3          = LCCR3_OutEnH | LCCR3_PixRsEdg | LCCR3_ACBsDiv(2),

        .backlight_power = assabet_lcd_backlight_power,
        .lcd_power = assabet_lcd_power,
        .set_visual = assabet_lcd_set_visual,
};
#else
static void assabet_pal_backlight_power(int on)
{
        ASSABET_BCR_clear(ASSABET_BCR_LIGHT_ON);
}

static void assabet_pal_power(int on)
{
        ASSABET_BCR_clear(ASSABET_BCR_LCD_ON);
}

static struct sa1100fb_mach_info pal_info = {
        .pixclock       = 67797,        .bpp            = 16,
        .xres           = 640,          .yres           = 512,

        .hsync_len      = 64,           .vsync_len      = 6,
        .left_margin    = 125,          .upper_margin   = 70,
        .right_margin   = 115,          .lower_margin   = 36,

        .lccr0          = LCCR0_Color | LCCR0_Sngl | LCCR0_Act,
        .lccr3          = LCCR3_OutEnH | LCCR3_PixRsEdg | LCCR3_ACBsDiv(512),

        .backlight_power = assabet_pal_backlight_power,
        .lcd_power = assabet_pal_power,
        .set_visual = assabet_lcd_set_visual,
};
#endif

#ifdef CONFIG_ASSABET_NEPONSET
static struct resource neponset_resources[] = {
        DEFINE_RES_MEM(0x10000000, 0x08000000),
        DEFINE_RES_MEM(0x18000000, 0x04000000),
        DEFINE_RES_MEM(0x40000000, SZ_8K),
        DEFINE_RES_IRQ(IRQ_GPIO25),
};
#endif

static struct gpiod_lookup_table assabet_cf_gpio_table = {
        .dev_id = "sa11x0-pcmcia.1",
        .table = {
                GPIO_LOOKUP("gpio", 21, "ready", GPIO_ACTIVE_HIGH),
                GPIO_LOOKUP("gpio", 22, "detect", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("gpio", 24, "bvd2", GPIO_ACTIVE_HIGH),
                GPIO_LOOKUP("gpio", 25, "bvd1", GPIO_ACTIVE_HIGH),
                GPIO_LOOKUP("assabet", 1, "reset", GPIO_ACTIVE_HIGH),
                GPIO_LOOKUP("assabet", 7, "bus-enable", GPIO_ACTIVE_LOW),
                { },
        },
};

static struct regulator_consumer_supply assabet_cf_vcc_consumers[] = {
        REGULATOR_SUPPLY("vcc", "sa11x0-pcmcia.1"),
};

static struct fixed_voltage_config assabet_cf_vcc_pdata __initdata = {
        .supply_name = "cf-power",
        .microvolts = 3300000,
};

static struct gpiod_lookup_table assabet_cf_vcc_gpio_table = {
        .dev_id = "reg-fixed-voltage.0",
        .table = {
                GPIO_LOOKUP("assabet", 0, NULL, GPIO_ACTIVE_HIGH),
                { },
        },
};

static struct gpio_led assabet_leds[] __initdata = {
        {
                .name = "assabet:red",
                .default_trigger = "cpu0",
                .active_low = 1,
                .default_state = LEDS_GPIO_DEFSTATE_KEEP,
        }, {
                .name = "assabet:green",
                .default_trigger = "heartbeat",
                .active_low = 1,
                .default_state = LEDS_GPIO_DEFSTATE_KEEP,
        },
};

static const struct gpio_led_platform_data assabet_leds_pdata __initconst = {
        .num_leds = ARRAY_SIZE(assabet_leds),
        .leds = assabet_leds,
};

static struct gpio_keys_button assabet_keys_buttons[] = {
        {
                .gpio = 0,
                .irq = IRQ_GPIO0,
                .desc = "gpio0",
                .wakeup = 1,
                .can_disable = 1,
                .debounce_interval = 5,
        }, {
                .gpio = 1,
                .irq = IRQ_GPIO1,
                .desc = "gpio1",
                .wakeup = 1,
                .can_disable = 1,
                .debounce_interval = 5,
        },
};

static const struct gpio_keys_platform_data assabet_keys_pdata = {
        .buttons = assabet_keys_buttons,
        .nbuttons = ARRAY_SIZE(assabet_keys_buttons),
        .rep = 0,
};

static struct gpiod_lookup_table assabet_uart1_gpio_table = {
        .dev_id = "sa11x0-uart.1",
        .table = {
                GPIO_LOOKUP("assabet", 16, "dtr", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("assabet", 17, "rts", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("assabet", 25, "dcd", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("assabet", 26, "cts", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("assabet", 27, "dsr", GPIO_ACTIVE_LOW),
                { },
        },
};

static struct gpiod_lookup_table assabet_uart3_gpio_table = {
        .dev_id = "sa11x0-uart.3",
        .table = {
                GPIO_LOOKUP("assabet", 28, "cts", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("assabet", 29, "dsr", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("assabet", 30, "dcd", GPIO_ACTIVE_LOW),
                GPIO_LOOKUP("assabet", 31, "rng", GPIO_ACTIVE_LOW),
                { },
        },
};

static void __init assabet_init(void)
{
        /*
         * Ensure that the power supply is in "high power" mode.
         */
        GPSR = GPIO_GPIO16;
        GPDR |= GPIO_GPIO16;

        /*
         * Ensure that these pins are set as outputs and are driving
         * logic 0.  This ensures that we won't inadvertently toggle
         * the WS latch in the CPLD, and we don't float causing
         * excessive power drain.  --rmk
         */
        GPCR = GPIO_SSP_TXD | GPIO_SSP_SCLK | GPIO_SSP_SFRM;
        GPDR |= GPIO_SSP_TXD | GPIO_SSP_SCLK | GPIO_SSP_SFRM;

        /*
         * Also set GPIO27 as an output; this is used to clock UART3
         * via the FPGA and as otherwise has no pullups or pulldowns,
         * so stop it floating.
         */
        GPCR = GPIO_GPIO27;
        GPDR |= GPIO_GPIO27;

        /*
         * Set up registers for sleep mode.
         */
        PWER = PWER_GPIO0;
        PGSR = 0;
        PCFR = 0;
        PSDR = 0;
        PPDR |= PPC_TXD3 | PPC_TXD1;
        PPSR |= PPC_TXD3 | PPC_TXD1;

        sa11x0_ppc_configure_mcp();

        if (machine_has_neponset()) {
#ifndef CONFIG_ASSABET_NEPONSET
                printk( "Warning: Neponset detected but full support "
                        "hasn't been configured in the kernel\n" );
#else
                platform_device_register_simple("neponset", 0,
                        neponset_resources, ARRAY_SIZE(neponset_resources));
#endif
        } else {
                gpiod_add_lookup_table(&assabet_uart1_gpio_table);
                gpiod_add_lookup_table(&assabet_uart3_gpio_table);
                gpiod_add_lookup_table(&assabet_cf_vcc_gpio_table);

                sa11x0_register_fixed_regulator(0, &assabet_cf_vcc_pdata,
                                        assabet_cf_vcc_consumers,
                                        ARRAY_SIZE(assabet_cf_vcc_consumers),
                                        true);

        }

        platform_device_register_resndata(NULL, "gpio-keys", 0,
                                          NULL, 0,
                                          &assabet_keys_pdata,
                                          sizeof(assabet_keys_pdata));

        gpio_led_register_device(-1, &assabet_leds_pdata);

#ifndef ASSABET_PAL_VIDEO
        sa11x0_register_lcd(&lq039q2ds54_info);
#else
        sa11x0_register_lcd(&pal_video);
#endif
        sa11x0_register_mtd(&assabet_flash_data, assabet_flash_resources,
                            ARRAY_SIZE(assabet_flash_resources));
        sa11x0_register_irda(&assabet_irda_data);
        sa11x0_register_mcp(&assabet_mcp_data);

        if (!machine_has_neponset())
                sa11x0_register_pcmcia(1, &assabet_cf_gpio_table);
}

/*
 * On Assabet, we must probe for the Neponset board _before_
 * paging_init() has occurred to actually determine the amount
 * of RAM available.  To do so, we map the appropriate IO section
 * in the page table here in order to access GPIO registers.
 */
static void __init map_sa1100_gpio_regs( void )
{
        unsigned long phys = __PREG(GPLR) & PMD_MASK;
        unsigned long virt = (unsigned long)io_p2v(phys);
        int prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_DOMAIN(DOMAIN_IO);
        pmd_t *pmd;

        pmd = pmd_offset(pud_offset(pgd_offset_k(virt), virt), virt);
        *pmd = __pmd(phys | prot);
        flush_pmd_entry(pmd);
}

/*
 * Read System Configuration "Register"
 * (taken from "Intel StrongARM SA-1110 Microprocessor Development Board
 * User's Guide", section 4.4.1)
 *
 * This same scan is performed in arch/arm/boot/compressed/head-sa1100.S
 * to set up the serial port for decompression status messages. We
 * repeat it here because the kernel may not be loaded as a zImage, and
 * also because it's a hassle to communicate the SCR value to the kernel
 * from the decompressor.
 *
 * Note that IRQs are guaranteed to be disabled.
 */
static void __init get_assabet_scr(void)
{
        unsigned long uninitialized_var(scr), i;

        GPDR |= 0x3fc;                  /* Configure GPIO 9:2 as outputs */
        GPSR = 0x3fc;                   /* Write 0xFF to GPIO 9:2 */
        GPDR &= ~(0x3fc);               /* Configure GPIO 9:2 as inputs */
        for(i = 100; i--; )             /* Read GPIO 9:2 */
                scr = GPLR;
        GPDR |= 0x3fc;                  /*  restore correct pin direction */
        scr &= 0x3fc;                   /* save as system configuration byte. */
        SCR_value = scr;
}

static void __init
fixup_assabet(struct tag *tags, char **cmdline)
{
        /* This must be done before any call to machine_has_neponset() */
        map_sa1100_gpio_regs();
        get_assabet_scr();

        if (machine_has_neponset())
                printk("Neponset expansion board detected\n");
}


static void assabet_uart_pm(struct uart_port *port, u_int state, u_int oldstate)
{
        if (port->mapbase == _Ser1UTCR0) {
                if (state)
                        ASSABET_BCR_clear(ASSABET_BCR_RS232EN);
                else
                        ASSABET_BCR_set(ASSABET_BCR_RS232EN);
        }
}

static struct sa1100_port_fns assabet_port_fns __initdata = {
        .pm             = assabet_uart_pm,
};

static struct map_desc assabet_io_desc[] __initdata = {
        {       /* Board Control Register */
                .virtual        =  0xf1000000,
                .pfn            = __phys_to_pfn(0x12000000),
                .length         = 0x00100000,
                .type           = MT_DEVICE
        }, {    /* MQ200 */
                .virtual        =  0xf2800000,
                .pfn            = __phys_to_pfn(0x4b800000),
                .length         = 0x00800000,
                .type           = MT_DEVICE
        }
};

static void __init assabet_map_io(void)
{
        sa1100_map_io();
        iotable_init(assabet_io_desc, ARRAY_SIZE(assabet_io_desc));

        /*
         * Set SUS bit in SDCR0 so serial port 1 functions.
         * Its called GPCLKR0 in my SA1110 manual.
         */
        Ser1SDCR0 |= SDCR0_SUS;
        MSC1 = (MSC1 & ~0xffff) |
                MSC_NonBrst | MSC_32BitStMem |
                MSC_RdAcc(2) | MSC_WrAcc(2) | MSC_Rec(0);

        if (!machine_has_neponset())
                sa1100_register_uart_fns(&assabet_port_fns);

        /*
         * When Neponset is attached, the first UART should be
         * UART3.  That's what Angel is doing and many documents
         * are stating this.
         *
         * We do the Neponset mapping even if Neponset support
         * isn't compiled in so the user will still get something on
         * the expected physical serial port.
         *
         * We no longer do this; not all boot loaders support it,
         * and UART3 appears to be somewhat unreliable with blob.
         */
        sa1100_register_uart(0, 1);
        sa1100_register_uart(2, 3);
}

void __init assabet_init_irq(void)
{
        unsigned int assabet_gpio_base;
        u32 def_val;

        sa1100_init_irq();

        if (machine_has_neponset())
                def_val = ASSABET_BCR_DB1111;
        else
                def_val = ASSABET_BCR_DB1110;

        /*
         * Angel sets this, but other bootloaders may not.
         *
         * This must precede any driver calls to BCR_set() or BCR_clear().
         */
        assabet_gpio_base = assabet_init_gpio((void *)&ASSABET_BCR, def_val);

        assabet_leds[0].gpio = assabet_gpio_base + 13;
        assabet_leds[1].gpio = assabet_gpio_base + 14;
}

MACHINE_START(ASSABET, "Intel-Assabet")
        .atag_offset    = 0x100,
        .fixup          = fixup_assabet,
        .map_io         = assabet_map_io,
        .nr_irqs        = SA1100_NR_IRQS,
        .init_irq       = assabet_init_irq,
        .init_time      = sa1100_timer_init,
        .init_machine   = assabet_init,
        .init_late      = sa11x0_init_late,
#ifdef CONFIG_SA1111
        .dma_zone_size  = SZ_1M,
#endif
        .restart        = sa11x0_restart,
MACHINE_END