openwrt-xburst/target/linux/atheros-2.6/files/arch/mips/atheros/ar5315.c

/*
 * 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.
 *
 * Copyright (C) 2003 Atheros Communications, Inc.,  All Rights Reserved.
 * Copyright (C) 2006 FON Technology, SL.
 * Copyright (C) 2006 Imre Kaloz <kaloz@openwrt.org>
 * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
 */

/*
 * Platform devices for Atheros SoCs
 */

#include <linux/autoconf.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/platform_device.h>
#include <linux/kernel.h>
#include <linux/reboot.h>
#include <asm/bootinfo.h>
#include <asm/reboot.h>
#include <asm/time.h>
#include <asm/irq.h>
#include <asm/io.h>
#include "ar531x.h"

static int is_5315 = 0;
static struct resource ar5315_eth_res[] = {
	{
		.name = "eth0_membase",
		.flags = IORESOURCE_MEM,
		.start = AR5315_ENET0,
		.end = AR5315_ENET0 + 0x2000,
	},
	{
		.name = "eth0_irq",
		.flags = IORESOURCE_IRQ,
		.start = AR5315_IRQ_ENET0_INTRS,
		.end = AR5315_IRQ_ENET0_INTRS,
	},
};

static struct ar531x_eth ar5315_eth_data = {
	.phy = 1,
	.mac = 0,
	.reset_base = AR5315_RESET,
	.reset_mac = AR5315_RESET_ENET0,
	.reset_phy = AR5315_RESET_EPHY0,
	.phy_base = AR5315_ENET0
};

static struct platform_device ar5315_eth = {
	.id = 0,
	.name = "ar531x-eth",
	.dev.platform_data = &ar5315_eth_data,
	.resource = ar5315_eth_res,
	.num_resources = ARRAY_SIZE(ar5315_eth_res)
};

static struct platform_device ar5315_wmac = {
	.id = 0,
	.name = "ar531x-wmac",
	/* FIXME: add resources */
};

static struct resource ar5315_spiflash_res[] = {
	{
		.name = "flash_base",
		.flags = IORESOURCE_MEM,
		.start = KSEG1ADDR(AR5315_SPI_READ),
		.end = KSEG1ADDR(AR5315_SPI_READ) + 0x800000,
	},
	{
		.name = "flash_regs",
		.flags = IORESOURCE_MEM,
		.start = 0x11300000,
		.end = 0x11300012,
	},
};

static struct platform_device ar5315_spiflash = {
	.id = 0,
	.name = "spiflash",
	.resource = ar5315_spiflash_res,
	.num_resources = ARRAY_SIZE(ar5315_spiflash_res)
};

static __initdata struct platform_device *ar5315_devs[4];



static void *flash_regs;

static inline __u32 spiflash_regread32(int reg)
{
	volatile __u32 *data = (__u32 *)(flash_regs + reg);

	return (*data);
}

static inline void spiflash_regwrite32(int reg, __u32 data)
{
	volatile __u32 *addr = (__u32 *)(flash_regs + reg);

	*addr = data;
}

#define SPI_FLASH_CTL      0x00
#define SPI_FLASH_OPCODE   0x04
#define SPI_FLASH_DATA     0x08

static __u8 spiflash_probe(void)
{
	 __u32 reg;

	do {
		reg = spiflash_regread32(SPI_FLASH_CTL);
	} while (reg & SPI_CTL_BUSY);

	spiflash_regwrite32(SPI_FLASH_OPCODE, 0xab);

	reg = (reg & ~SPI_CTL_TX_RX_CNT_MASK) | 4 |
        	(1 << 4) | SPI_CTL_START;

	spiflash_regwrite32(SPI_FLASH_CTL, reg);
 
	do {
  		reg = spiflash_regread32(SPI_FLASH_CTL);
	} while (reg & SPI_CTL_BUSY);

	reg = (__u32) spiflash_regread32(SPI_FLASH_DATA);
	reg &= 0xff;

	return (u8) reg;
}


#define STM_8MBIT_SIGNATURE     0x13
#define STM_16MBIT_SIGNATURE    0x14
#define STM_32MBIT_SIGNATURE    0x15
#define STM_64MBIT_SIGNATURE    0x16
#define STM_128MBIT_SIGNATURE   0x17


static char __init *ar5315_flash_limit(void)
{
	u8 sig;
	u32 flash_size = 0;

	/* probe the flash chip size */
	flash_regs = ioremap_nocache(ar5315_spiflash_res[1].start, ar5315_spiflash_res[1].end - ar5315_spiflash_res[1].start);
	sig = spiflash_probe();
	iounmap(flash_regs);

	switch(sig) {
		case STM_8MBIT_SIGNATURE:
			flash_size = 0x00100000;
			break;
		case STM_16MBIT_SIGNATURE:
			flash_size = 0x00200000;
			break;
		case STM_32MBIT_SIGNATURE:
			flash_size = 0x00400000;
			break;
		case STM_64MBIT_SIGNATURE:
			flash_size = 0x00800000;
			break;
		case STM_128MBIT_SIGNATURE:
			flash_size = 0x01000000;
			break;
	}

	ar5315_spiflash_res[0].end = ar5315_spiflash_res[0].start + flash_size;
	return (char *) ar5315_spiflash_res[0].end;
}

int __init ar5315_init_devices(void)
{
	struct ar531x_config *config;
	struct ar531x_boarddata *bcfg;
	u32 devid;
	int dev = 0;

	if (!is_5315)
		return 0;

	/* Find board configuration */
	ar531x_find_config(ar5315_flash_limit());
	bcfg = (struct ar531x_boarddata *) board_config;

#if 0
	/* Detect the hardware based on the device ID */
	devid = sysRegRead(AR5315_SREV) & AR5315_REV_MAJ >> AR5315_REV_MAJ_S;
	switch(devid) {
		case 0x9:
			mips_machtype = MACH_ATHEROS_AR2317;
			break;
		/* FIXME: how can we detect AR2316? */
		case 0x8:
		default:
			mips_machtype = MACH_ATHEROS_AR2315;
			break;
	}
#endif

	config = (struct ar531x_config *) kzalloc(sizeof(struct ar531x_config), GFP_KERNEL);
	config->board = board_config;
	config->radio = radio_config;
	config->unit = 0;
	config->tag = (u_int16_t) (sysRegRead(AR5315_SREV) & AR5315_REV_CHIP);
	
	ar5315_eth_data.board_config = board_config;
	ar5315_eth_data.macaddr = bcfg->enet0Mac;
	ar5315_wmac.dev.platform_data = config;
	
	ar5315_devs[dev++] = &ar5315_eth;
	ar5315_devs[dev++] = &ar5315_wmac;
	ar5315_devs[dev++] = &ar5315_spiflash;

	return platform_add_devices(ar5315_devs, dev);
}


/*
 * Called when an interrupt is received, this function
 * determines exactly which interrupt it was, and it
 * invokes the appropriate handler.
 *
 * Implicitly, we also define interrupt priority by
 * choosing which to dispatch first.
 */
asmlinkage void ar5315_irq_dispatch(void)
{
	int pending = read_c0_status() & read_c0_cause();

	if (pending & CAUSEF_IP3)
		do_IRQ(AR5315_IRQ_WLAN0_INTRS);
	else if (pending & CAUSEF_IP4)
		do_IRQ(AR5315_IRQ_ENET0_INTRS);
	else if (pending & CAUSEF_IP2) {
		unsigned int ar531x_misc_intrs = sysRegRead(AR5315_ISR) & sysRegRead(AR5315_IMR);

	    if (ar531x_misc_intrs & AR5315_ISR_TIMER)
			do_IRQ(AR531X_MISC_IRQ_TIMER);
		else if (ar531x_misc_intrs & AR5315_ISR_AHB)
			do_IRQ(AR531X_MISC_IRQ_AHB_PROC);
		else if (ar531x_misc_intrs & AR5315_ISR_GPIO) {
			sysRegWrite(AR5315_ISR, sysRegRead(AR5315_IMR) | ~AR5315_ISR_GPIO);
		} else if (ar531x_misc_intrs & AR5315_ISR_UART0)
			do_IRQ(AR531X_MISC_IRQ_UART0);
		else if (ar531x_misc_intrs & AR5315_ISR_WD)
			do_IRQ(AR531X_MISC_IRQ_WATCHDOG);
		else
			do_IRQ(AR531X_MISC_IRQ_NONE);
	} else if (pending & CAUSEF_IP7)
		do_IRQ(AR531X_IRQ_CPU_CLOCK);
	else
		do_IRQ(AR531X_IRQ_NONE);
}

static void ar5315_halt(void)
{
	 while (1);
}

static void ar5315_power_off(void)
{
	 ar5315_halt();
}


static void ar5315_restart(char *command)
{
	unsigned int reg;
	for(;;) {
		
		/* reset the system */
		sysRegWrite(AR5315_COLD_RESET,AR5317_RESET_SYSTEM);

		/* 
		 * Cold reset does not work on the AR2315/6, use the GPIO reset bits a workaround.
		 */

		reg = sysRegRead(AR5315_GPIO_DO);
		reg &= ~(1 << AR5315_RESET_GPIO);
		sysRegWrite(AR5315_GPIO_DO, reg);
		(void)sysRegRead(AR5315_GPIO_DO); /* flush write to hardware */
	}
}


/*
 * This table is indexed by bits 5..4 of the CLOCKCTL1 register
 * to determine the predevisor value.
 */
static int __initdata CLOCKCTL1_PREDIVIDE_TABLE[4] = {
    1,
    2,
    4,
    5
};

static int __initdata PLLC_DIVIDE_TABLE[5] = {
    2,
    3,
    4,
    6,
    3
};

static unsigned int __init
ar5315_sys_clk(unsigned int clockCtl)
{
    unsigned int pllcCtrl,cpuDiv;
    unsigned int pllcOut,refdiv,fdiv,divby2;
	unsigned int clkDiv;

    pllcCtrl = sysRegRead(AR5315_PLLC_CTL);
    refdiv = (pllcCtrl & PLLC_REF_DIV_M) >> PLLC_REF_DIV_S;
    refdiv = CLOCKCTL1_PREDIVIDE_TABLE[refdiv];
    fdiv = (pllcCtrl & PLLC_FDBACK_DIV_M) >> PLLC_FDBACK_DIV_S;
    divby2 = (pllcCtrl & PLLC_ADD_FDBACK_DIV_M) >> PLLC_ADD_FDBACK_DIV_S;
    divby2 += 1;
    pllcOut = (40000000/refdiv)*(2*divby2)*fdiv;


    /* clkm input selected */
	switch(clockCtl & CPUCLK_CLK_SEL_M) {
		case 0:
		case 1:
			clkDiv = PLLC_DIVIDE_TABLE[(pllcCtrl & PLLC_CLKM_DIV_M) >> PLLC_CLKM_DIV_S];
			break;
		case 2:
			clkDiv = PLLC_DIVIDE_TABLE[(pllcCtrl & PLLC_CLKC_DIV_M) >> PLLC_CLKC_DIV_S];
			break;
		default:
			pllcOut = 40000000;
			clkDiv = 1;
			break;
	}
	cpuDiv = (clockCtl & CPUCLK_CLK_DIV_M) >> CPUCLK_CLK_DIV_S;  
	cpuDiv = cpuDiv * 2 ?: 1;
	return (pllcOut/(clkDiv * cpuDiv));
}
		
static inline unsigned int ar5315_cpu_frequency(void)
{
    return ar5315_sys_clk(sysRegRead(AR5315_CPUCLK));
}

static inline unsigned int ar5315_apb_frequency(void)
{
    return ar5315_sys_clk(sysRegRead(AR5315_AMBACLK));
}

static void __init ar5315_time_init(void)
{
	mips_hpt_frequency = ar5315_cpu_frequency() / 2;
}



/* Enable the specified AR531X_MISC_IRQ interrupt */
static void
ar5315_misc_intr_enable(unsigned int irq)
{
	unsigned int imr;

	imr = sysRegRead(AR5315_IMR);
	switch(irq)
	{
	   case AR531X_MISC_IRQ_TIMER:
	     imr |= AR5315_ISR_TIMER;
	     break;

	   case AR531X_MISC_IRQ_AHB_PROC:
	     imr |= AR5315_ISR_AHB;
	     break;

	   case AR531X_MISC_IRQ_AHB_DMA:
	     imr |= 0/* ?? */;
	     break;

	   case	AR531X_MISC_IRQ_GPIO:
	     imr |= AR5315_ISR_GPIO;
	     break;

	   case AR531X_MISC_IRQ_UART0:
	     imr |= AR5315_ISR_UART0;
	     break;


	   case	AR531X_MISC_IRQ_WATCHDOG:
	     imr |= AR5315_ISR_WD;
	     break;

	   case AR531X_MISC_IRQ_LOCAL:
	     imr |= 0/* ?? */;
	     break;

	}
	sysRegWrite(AR5315_IMR, imr);
	imr=sysRegRead(AR5315_IMR); /* flush write buffer */
}

/* Disable the specified AR531X_MISC_IRQ interrupt */
static void
ar5315_misc_intr_disable(unsigned int irq)
{
	unsigned int imr;

	imr = sysRegRead(AR5315_IMR);
	switch(irq)
	{
	   case AR531X_MISC_IRQ_TIMER:
	     imr &= (~AR5315_ISR_TIMER);
	     break;

	   case AR531X_MISC_IRQ_AHB_PROC:
	     imr &= (~AR5315_ISR_AHB);
	     break;

	   case AR531X_MISC_IRQ_AHB_DMA:
	     imr &= 0/* ?? */;
	     break;

	   case	AR531X_MISC_IRQ_GPIO:
	     imr &= ~AR5315_ISR_GPIO;
	     break;

	   case AR531X_MISC_IRQ_UART0:
	     imr &= (~AR5315_ISR_UART0);
	     break;

	   case	AR531X_MISC_IRQ_WATCHDOG:
	     imr &= (~AR5315_ISR_WD);
	     break;

	   case AR531X_MISC_IRQ_LOCAL:
	     imr &= ~0/* ?? */;
	     break;

	}
	sysRegWrite(AR5315_IMR, imr);
	sysRegRead(AR5315_IMR); /* flush write buffer */
}

/* Turn on the specified AR531X_MISC_IRQ interrupt */
static unsigned int
ar5315_misc_intr_startup(unsigned int irq)
{
	ar5315_misc_intr_enable(irq);
	return 0;
}

/* Turn off the specified AR531X_MISC_IRQ interrupt */
static void
ar5315_misc_intr_shutdown(unsigned int irq)
{
	ar5315_misc_intr_disable(irq);
}

static void
ar5315_misc_intr_ack(unsigned int irq)
{
	ar5315_misc_intr_disable(irq);
}

static void
ar5315_misc_intr_end(unsigned int irq)
{
	if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
		ar5315_misc_intr_enable(irq);
}

static struct irq_chip ar5315_misc_intr_controller = {
	.typename	= "AR5315 misc",
	.startup	= ar5315_misc_intr_startup,
	.shutdown	= ar5315_misc_intr_shutdown,
	.enable		= ar5315_misc_intr_enable,
	.disable	= ar5315_misc_intr_disable,
	.ack		= ar5315_misc_intr_ack,
	.end		= ar5315_misc_intr_end,
};

static irqreturn_t ar5315_ahb_proc_handler(int cpl, void *dev_id)
{
    sysRegWrite(AR5315_AHB_ERR0,AHB_ERROR_DET);
    sysRegRead(AR5315_AHB_ERR1);

    printk("AHB fatal error\n");
    machine_restart("AHB error"); /* Catastrophic failure */

    return IRQ_HANDLED;
}

static struct irqaction ar5315_ahb_proc_interrupt  = {
	.handler	= ar5315_ahb_proc_handler,
	.flags		= SA_INTERRUPT,
	.name		= "ar5315_ahb_proc_interrupt",
};


static struct irqaction cascade  = {
	.handler	= no_action,
	.flags		= SA_INTERRUPT,
	.name		= "cascade",
};

void ar5315_misc_intr_init(int irq_base)
{
	int i;

	for (i = irq_base; i < irq_base + AR531X_MISC_IRQ_COUNT; i++) {
		irq_desc[i].status = IRQ_DISABLED;
		irq_desc[i].action = NULL;
		irq_desc[i].depth = 1;
		irq_desc[i].chip = &ar5315_misc_intr_controller;
	}
	setup_irq(AR531X_MISC_IRQ_AHB_PROC, &ar5315_ahb_proc_interrupt);
	setup_irq(AR5315_IRQ_MISC_INTRS, &cascade);
}

void __init ar5315_prom_init(void)
{
	u32 memsize, memcfg;

	is_5315 = 1;
	memcfg = sysRegRead(AR5315_MEM_CFG);
	memsize   = 1 + ((memcfg & SDRAM_DATA_WIDTH_M) >> SDRAM_DATA_WIDTH_S);
	memsize <<= 1 + ((memcfg & SDRAM_COL_WIDTH_M) >> SDRAM_COL_WIDTH_S);
	memsize <<= 1 + ((memcfg & SDRAM_ROW_WIDTH_M) >> SDRAM_ROW_WIDTH_S);
	memsize <<= 3;
	add_memory_region(0, memsize, BOOT_MEM_RAM);

	/* Initialize it to AR2315 for now. Real detection will be done
	 * in ar5315_init_devices() */
	mips_machtype = MACH_ATHEROS_AR2315;
}

void __init ar5315_plat_setup(void)
{
	unsigned int config = read_c0_config();

	/* Clear any lingering AHB errors */
	write_c0_config(config & ~0x3);
	sysRegWrite(AR5315_AHB_ERR0,AHB_ERROR_DET);
	sysRegRead(AR5315_AHB_ERR1);
	sysRegWrite(AR5315_WDC, WDC_IGNORE_EXPIRATION);

	board_time_init = ar5315_time_init;

	_machine_restart = ar5315_restart;
	_machine_halt = ar5315_halt;
	pm_power_off = ar5315_power_off;

	serial_setup(KSEG1ADDR(AR5315_UART0), ar5315_apb_frequency());
}

arch_initcall(ar5315_init_devices);