assabet.c

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/*
 * linux/arch/arm/mach-sa1100/assabet.c
 *
 * Author: Nicolas Pitre
 *
 * This file contains all Assabet-specific tweaks.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/config.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/serial_core.h>

#include <asm/hardware.h>
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/pgtable.h>

#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#include <asm/mach/serial_sa1100.h>
#include <asm/arch/assabet.h>

#include "generic.h"

#define ASSABET_BCR_DB1110 \
	(ASSABET_BCR_SPK_OFF    | ASSABET_BCR_QMUTE     | \
	 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_QMUTE     | \
	 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	| \
	 ASSABET_BCR_CODEC_RST  )

unsigned long SCR_value = ASSABET_SCR_INIT;
EXPORT_SYMBOL(SCR_value);

static unsigned long BCR_value = ASSABET_BCR_DB1110;

void ASSABET_BCR_frob(unsigned int mask, unsigned int val)
{
	unsigned long flags;

	local_irq_save(flags);
	BCR_value = (BCR_value & ~mask) | val;
	ASSABET_BCR = BCR_value;
	local_irq_restore(flags);
}

EXPORT_SYMBOL(ASSABET_BCR_frob);


static int __init assabet_init(void)
{
	if (!machine_is_assabet())
		return -EINVAL;

	/*
	 * Set the IRQ edges
	 */
	set_GPIO_IRQ_edge(GPIO_GPIO23, GPIO_RISING_EDGE);	/* UCB1300 */

	if (machine_has_neponset()) {
		/*
		 * Angel sets this, but other bootloaders may not.
		 *
		 * This must precede any driver calls to BCR_set()
		 * or BCR_clear().
		 */
		ASSABET_BCR = BCR_value = ASSABET_BCR_DB1111;
		NCR_0 = 0;

#ifndef CONFIG_ASSABET_NEPONSET
		printk( "Warning: Neponset detected but full support "
			"hasn't been configured in the kernel\n" );
#endif
	}

	return 0;
}

__initcall(assabet_init);


/*
 * 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 = io_p2v(phys);
	int prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_DOMAIN(DOMAIN_IO);
	pmd_t pmd;
	pmd_val(pmd) = phys | prot;
	set_pmd(pmd_offset(pgd_offset_k(virt), virt), 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 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--; scr = GPLR);	/* Read GPIO 9:2 */
	GPDR |= 0x3fc;			/*  restore correct pin direction */
	scr &= 0x3fc;			/* save as system configuration byte. */
	SCR_value = scr;
}

extern void convert_to_tag_list(struct param_struct *params, int mem_init);

static void __init
fixup_assabet(struct machine_desc *desc, struct param_struct *params,
	      char **cmdline, struct meminfo *mi)
{
	struct tag *t = (struct tag *)params;

	/* 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");

	/*
	 * Apparantly bootldr uses a param_struct.  Groan.
	 */
	if (t->hdr.tag != ATAG_CORE)
		convert_to_tag_list(params, 1);

	if (t->hdr.tag != ATAG_CORE) {
		t->hdr.tag = ATAG_CORE;
		t->hdr.size = tag_size(tag_core);
		t->u.core.flags = 0;
		t->u.core.pagesize = PAGE_SIZE;
		t->u.core.rootdev = RAMDISK_MAJOR << 8 | 0;
		t = tag_next(t);

		t->hdr.tag = ATAG_MEM;
		t->hdr.size = tag_size(tag_mem32);
		t->u.mem.start = 0xc0000000;
		t->u.mem.size  = 32 * 1024 * 1024;
		t = tag_next(t);


		/*
		 * Note that Neponset RAM is slower...
		 * and still untested.
		 * This would be a candidate for
		 * _real_ NUMA support.
		 */
		if (machine_has_neponset() && 0) {
			t->hdr.tag = ATAG_MEM;
			t->hdr.size = tag_size(tag_mem32);
			t->u.mem.start = 0xd0000000;
			t->u.mem.size  = 32 * 1024 * 1024;
			t = tag_next(t);
		}

		t->hdr.tag = ATAG_RAMDISK;
		t->hdr.size = tag_size(tag_ramdisk);
		t->u.ramdisk.flags = 1;
		t->u.ramdisk.size = 8192;
		t->u.ramdisk.start = 0;
		t = tag_next(t);

		t->hdr.tag = ATAG_INITRD;
		t->hdr.size = tag_size(tag_initrd);
		t->u.initrd.start = 0xc0800000;
		t->u.initrd.size = 3 * 1024 * 1024;
		t = tag_next(t);

		t->hdr.tag = ATAG_NONE;
		t->hdr.size = 0;
	}
}


static struct map_desc assabet_io_desc[] __initdata = {
 /* virtual     physical    length      domain     r  w  c  b */
  { 0xe8000000, 0x00000000, 0x02000000, DOMAIN_IO, 0, 1, 0, 0 }, /* Flash bank 0 */
  { 0xf1000000, 0x12000000, 0x00100000, DOMAIN_IO, 0, 1, 0, 0 }, /* Board Control Register */
  { 0xf2800000, 0x4b800000, 0x00800000, DOMAIN_IO, 0, 1, 0, 0 }, /* MQ200 */
  /*  f3000000 - neponset system registers */
  /*  f4000000 - neponset SA1111 registers */
  LAST_DESC
};

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 |
					  ASSABET_BCR_COM_RTS |
					  ASSABET_BCR_COM_DTR);
		else
			ASSABET_BCR_set(ASSABET_BCR_RS232EN |
					ASSABET_BCR_COM_RTS |
					ASSABET_BCR_COM_DTR);
	}
}

/*
 * Assabet uses COM_RTS and COM_DTR for both UART1 (com port)
 * and UART3 (radio module).  We only handle them for UART1 here.
 */
static void assabet_set_mctrl(struct uart_port *port, u_int mctrl)
{
	if (port->mapbase == _Ser1UTCR0) {
		u_int set = 0, clear = 0;

		if (mctrl & TIOCM_RTS)
			clear |= ASSABET_BCR_COM_RTS;
		else
			set |= ASSABET_BCR_COM_RTS;

		if (mctrl & TIOCM_DTR)
			clear |= ASSABET_BCR_COM_DTR;
		else
			set |= ASSABET_BCR_COM_DTR;

		ASSABET_BCR_clear(clear);
		ASSABET_BCR_set(set);
	}
}

static u_int assabet_get_mctrl(struct uart_port *port)
{
	u_int ret = 0;
	u_int bsr = ASSABET_BSR;

	/* need 2 reads to read current value */
	bsr = ASSABET_BSR;

	if (port->mapbase == _Ser1UTCR0) {
		if (bsr & ASSABET_BSR_COM_DCD)
			ret |= TIOCM_CD;
		if (bsr & ASSABET_BSR_COM_CTS)
			ret |= TIOCM_CTS;
		if (bsr & ASSABET_BSR_COM_DSR)
			ret |= TIOCM_DSR;
	} else if (port->mapbase == _Ser3UTCR0) {
		if (bsr & ASSABET_BSR_RAD_DCD)
			ret |= TIOCM_CD;
		if (bsr & ASSABET_BSR_RAD_CTS)
			ret |= TIOCM_CTS;
		if (bsr & ASSABET_BSR_RAD_DSR)
			ret |= TIOCM_DSR;
		if (bsr & ASSABET_BSR_RAD_RI)
			ret |= TIOCM_RI;
	} else {
		ret = TIOCM_CD | TIOCM_CTS | TIOCM_DSR;
	}

	return ret;
}

static struct sa1100_port_fns assabet_port_fns __initdata = {
	set_mctrl:	assabet_set_mctrl,
	get_mctrl:	assabet_get_mctrl,
	pm:		assabet_uart_pm,
};

static void __init assabet_map_io(void)
{
	extern void neponset_map_io(void);

	sa1100_map_io();
	iotable_init(assabet_io_desc);

#ifdef CONFIG_ASSABET_NEPONSET
	/*
	 * We map Neponset registers even if it isn't present since
	 * many drivers will try to probe their stuff (and fail).
	 * This is still more friendly than a kernel paging request
	 * crash.
	 */
	neponset_map_io();
#endif

	if (machine_has_neponset()) {
		/*
		 * 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.
		 */
		sa1100_register_uart(0, 3);
		sa1100_register_uart(2, 1);
		/*
		 * Set SUS bit in SDCR0 so serial port 1 functions.
		 * Its called GPCLKR0 in my SA1110 manual.
		 */
		Ser1SDCR0 |= SDCR0_SUS;
	} else {
		sa1100_register_uart_fns(&assabet_port_fns);
		sa1100_register_uart(0, 1);	/* com port */
		sa1100_register_uart(2, 3);	/* radio module */
	}

	/*
	 * 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
	 */
	GPDR |= GPIO_SSP_TXD | GPIO_SSP_SCLK | GPIO_SSP_SFRM;
	GPCR = GPIO_SSP_TXD | GPIO_SSP_SCLK | GPIO_SSP_SFRM;

	/*
	 * Set up registers for sleep mode.
	 */
	PWER = PWER_GPIO0;
	PGSR = 0;
	PCFR = 0;
	PSDR = 0;
}


MACHINE_START(ASSABET, "Intel-Assabet")
	BOOT_MEM(0xc0000000, 0x80000000, 0xf8000000)
	BOOT_PARAMS(0xc0000100)
	FIXUP(fixup_assabet)
	MAPIO(assabet_map_io)
	INITIRQ(sa1100_init_irq)
MACHINE_END