/* $Id: s3c2410_uart.c,v 1.4 2008/12/11 12:18:17 ecd Exp $
 */

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <errno.h>

#include <x49gp.h>
#include <s3c2410.h>
#include <s3c2410_intc.h>


typedef struct {
	uint32_t			ulcon;
	uint32_t			ucon;
	uint32_t			ufcon;
	uint32_t			umcon;
	uint32_t			utrstat;
	uint32_t			uerstat;
	uint32_t			ufstat;
	uint32_t			umstat;
	uint32_t			utxh;
	uint32_t			urxh;
	uint32_t			ubrdiv;

	int			int_err;
	int			int_txd;
	int			int_rxd;

	unsigned int		nr_regs;
	s3c2410_offset_t	*regs;

	x49gp_t			*x49gp;
} s3c2410_uart_reg_t;

typedef struct {
	s3c2410_uart_reg_t	uart[3];
} s3c2410_uart_t;

static int
s3c2410_uart_data_init(s3c2410_uart_t *uart)
{
	s3c2410_offset_t regs0[] = {
		S3C2410_OFFSET(UART0, ULCON, 0x00000000, uart->uart[0].ulcon),
		S3C2410_OFFSET(UART0, UCON, 0x00000000, uart->uart[0].ucon),
		S3C2410_OFFSET(UART0, UFCON, 0x00000000, uart->uart[0].ufcon),
		S3C2410_OFFSET(UART0, UMCON, 0x00000000, uart->uart[0].umcon),
		S3C2410_OFFSET(UART0, UTRSTAT, 0x00000006, uart->uart[0].utrstat),
		S3C2410_OFFSET(UART0, UERSTAT, 0x00000000, uart->uart[0].uerstat),
		S3C2410_OFFSET(UART0, UFSTAT, 0x00000000, uart->uart[0].ufstat),
		S3C2410_OFFSET(UART0, UMSTAT, 0x00000000, uart->uart[0].umstat),
		S3C2410_OFFSET(UART0, UTXH, 0, uart->uart[0].utxh),
		S3C2410_OFFSET(UART0, URXH, 0, uart->uart[0].urxh),
		S3C2410_OFFSET(UART0, UBRDIV, 0, uart->uart[0].ubrdiv)
	};
	s3c2410_offset_t regs1[] = {
		S3C2410_OFFSET(UART1, ULCON, 0x00000000, uart->uart[1].ulcon),
		S3C2410_OFFSET(UART1, UCON, 0x00000000, uart->uart[1].ucon),
		S3C2410_OFFSET(UART1, UFCON, 0x00000000, uart->uart[1].ufcon),
		S3C2410_OFFSET(UART1, UMCON, 0x00000000, uart->uart[1].umcon),
		S3C2410_OFFSET(UART1, UTRSTAT, 0x00000006, uart->uart[1].utrstat),
		S3C2410_OFFSET(UART1, UERSTAT, 0x00000000, uart->uart[1].uerstat),
		S3C2410_OFFSET(UART1, UFSTAT, 0x00000000, uart->uart[1].ufstat),
		S3C2410_OFFSET(UART1, UMSTAT, 0x00000000, uart->uart[1].umstat),
		S3C2410_OFFSET(UART1, UTXH, 0, uart->uart[1].utxh),
		S3C2410_OFFSET(UART1, URXH, 0, uart->uart[1].urxh),
		S3C2410_OFFSET(UART1, UBRDIV, 0, uart->uart[1].ubrdiv)
	};
	s3c2410_offset_t regs2[] = {
		S3C2410_OFFSET(UART2, ULCON, 0x00000000, uart->uart[2].ulcon),
		S3C2410_OFFSET(UART2, UCON, 0x00000000, uart->uart[2].ucon),
		S3C2410_OFFSET(UART2, UFCON, 0x00000000, uart->uart[2].ufcon),
		S3C2410_OFFSET(UART2, UTRSTAT, 0x00000006, uart->uart[2].utrstat),
		S3C2410_OFFSET(UART2, UERSTAT, 0x00000000, uart->uart[2].uerstat),
		S3C2410_OFFSET(UART2, UFSTAT, 0x00000000, uart->uart[2].ufstat),
		S3C2410_OFFSET(UART2, UTXH, 0, uart->uart[2].utxh),
		S3C2410_OFFSET(UART2, URXH, 0, uart->uart[2].urxh),
		S3C2410_OFFSET(UART2, UBRDIV, 0, uart->uart[2].ubrdiv)
	};

	uart->uart[0].regs = malloc(sizeof(regs0));
	if (NULL == uart->uart[0].regs) {
		fprintf(stderr, "%s:%u: Out of memory\n",
			__FUNCTION__, __LINE__);
		return -ENOMEM;
	}
	uart->uart[1].regs = malloc(sizeof(regs1));
	if (NULL == uart->uart[1].regs) {
		fprintf(stderr, "%s:%u: Out of memory\n",
			__FUNCTION__, __LINE__);
		free(uart->uart[0].regs);
		return -ENOMEM;
	}
	uart->uart[2].regs = malloc(sizeof(regs2));
	if (NULL == uart->uart[2].regs) {
		fprintf(stderr, "%s:%u: Out of memory\n",
			__FUNCTION__, __LINE__);
		free(uart->uart[0].regs);
		free(uart->uart[1].regs);
		return -ENOMEM;
	}

	memcpy(uart->uart[0].regs, regs0, sizeof(regs0));
	uart->uart[0].nr_regs = sizeof(regs0) / sizeof(regs0[0]);
	uart->uart[0].int_err = SUB_INT_ERR0;
	uart->uart[0].int_txd = SUB_INT_TXD0;
	uart->uart[0].int_rxd = SUB_INT_RXD0;

	memcpy(uart->uart[1].regs, regs1, sizeof(regs1));
	uart->uart[1].nr_regs = sizeof(regs1) / sizeof(regs1[0]);
	uart->uart[1].int_err = SUB_INT_ERR1;
	uart->uart[1].int_txd = SUB_INT_TXD1;
	uart->uart[1].int_rxd = SUB_INT_RXD1;

	memcpy(uart->uart[2].regs, regs2, sizeof(regs2));
	uart->uart[2].nr_regs = sizeof(regs2) / sizeof(regs2[0]);
	uart->uart[2].int_err = SUB_INT_ERR2;
	uart->uart[2].int_txd = SUB_INT_TXD2;
	uart->uart[2].int_rxd = SUB_INT_RXD2;

	return 0;
}

static uint32_t
s3c2410_uart_read(void *opaque, target_phys_addr_t offset)
{
	s3c2410_uart_reg_t *uart_regs = opaque;
	x49gp_t *x49gp = uart_regs->x49gp;
	s3c2410_offset_t *reg;
#ifdef DEBUG_S3C2410_UART
	const char *module;
	uint32_t mod_offset;
	uint32_t base;

	base = (offset & 0x0000c000) >> 14;

	switch (base) {
	case 0:
		module = "s3c2410-uart0";
		mod_offset = S3C2410_UART0_BASE;
		break;
	case 1:
		module = "s3c2410-uart1";
		mod_offset = S3C2410_UART1_BASE;
		break;
	case 2:
		module = "s3c2410-uart2";
		mod_offset = S3C2410_UART2_BASE;
		break;
	default:
		return ~(0);
	}
#endif

	offset &= ~(0xffffc000);
	if (! S3C2410_OFFSET_OK(uart_regs, offset)) {
		return ~(0);
	}

	reg = S3C2410_OFFSET_ENTRY(uart_regs, offset);

#ifdef DEBUG_S3C2410_UART
	printf("read  %s [%08x] %s [%08lx] data %08x\n",
		module, mod_offset, reg->name, (unsigned long) offset, *(reg->datap));
#endif

	switch (offset) {
	case S3C2410_UART0_URXH:
		uart_regs->utrstat &= ~(1 << 0);

		if (uart_regs->ucon & (1 << 8)) {
			s3c2410_intc_sub_deassert(x49gp, uart_regs->int_rxd);
		}

		break;
	}

	return *(reg->datap);
}

static void
s3c2410_uart_write(void *opaque, target_phys_addr_t offset, uint32_t data)
{
	s3c2410_uart_reg_t *uart_regs = opaque;
	x49gp_t *x49gp = uart_regs->x49gp;
	s3c2410_offset_t *reg;
	uint32_t base;
#ifdef DEBUG_S3C2410_UART
	const char *module;
	uint32_t mod_offset, ubrdivn, baud;
#endif

	base = (offset & 0x0000c000) >> 14;

#ifdef DEBUG_S3C2410_UART
	switch (base) {
	case 0:
		module = "s3c2410-uart0";
		mod_offset = S3C2410_UART0_BASE;
		break;
	case 1:
		module = "s3c2410-uart1";
		mod_offset = S3C2410_UART1_BASE;
		break;
	case 2:
		module = "s3c2410-uart2";
		mod_offset = S3C2410_UART2_BASE;
		break;
	default:
		return;
	}
#endif

	offset &= ~(0xffffc000);
	if (! S3C2410_OFFSET_OK(uart_regs, offset)) {
		return;
	}

	reg = S3C2410_OFFSET_ENTRY(uart_regs, offset);

#ifdef DEBUG_S3C2410_UART
	printf("write %s [%08x] %s [%08lx] data %08x\n",
		module, mod_offset, reg->name, (unsigned long) offset, data);
#endif

	*(reg->datap) = data;

	switch (offset) {
	case S3C2410_UART0_UCON:
		if (*(reg->datap) & (1 << 9))
			s3c2410_intc_sub_assert(x49gp, uart_regs->int_txd, 1);
		if (*(reg->datap) & (1 << 8))
			s3c2410_intc_sub_deassert(x49gp, uart_regs->int_rxd);
		break;

	case S3C2410_UART0_UBRDIV:
#ifdef DEBUG_S3C2410_UART
		ubrdivn = (data >> 0) & 0xffff;
		if (uart_regs->ucon & (1 << 10)) {
			baud = x49gp->UCLK / 16 / (ubrdivn + 1);
			printf("%s: UEXTCLK %u, ubrdivn %u, baud %u\n",
				module, x49gp->UCLK, ubrdivn, baud);
		} else {
			baud = x49gp->PCLK / 16 / (ubrdivn + 1);
			printf("%s: PCLK %u, ubrdivn %u, baud %u\n",
				module, x49gp->PCLK, ubrdivn, baud);
		}
#endif
		break;

	case S3C2410_UART0_UTXH:
		if (uart_regs->ucon & (1 << 9))
			s3c2410_intc_sub_deassert(x49gp, uart_regs->int_txd);

		uart_regs->utrstat |= (1 << 2) | (1 << 1);

		if (uart_regs->ucon & (1 << 9))
			s3c2410_intc_sub_assert(x49gp, uart_regs->int_txd, 1);
		else
			s3c2410_intc_sub_assert(x49gp, uart_regs->int_txd, 0);

		if (uart_regs->ucon & (1 << 5)) {
			uart_regs->urxh = data;
			uart_regs->utrstat |= (1 << 0);

			if (uart_regs->ucon & (1 << 8))
				s3c2410_intc_sub_assert(x49gp, uart_regs->int_rxd, 1);
			else
				s3c2410_intc_sub_assert(x49gp, uart_regs->int_rxd, 0);
		} else if (base == 2) {
			uart_regs->urxh = data;
			uart_regs->utrstat |= (1 << 0);

			if (uart_regs->ucon & (1 << 8))
				s3c2410_intc_sub_assert(x49gp, uart_regs->int_rxd, 1);
			else
				s3c2410_intc_sub_assert(x49gp, uart_regs->int_rxd, 0);
		}

		break;
	}
}

static int
s3c2410_uart_load(x49gp_module_t *module, GKeyFile *key)
{
	s3c2410_uart_reg_t *uart_regs = module->user_data;
	s3c2410_offset_t *reg;
	int error = 0;
	int i;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	for (i = 0; i < uart_regs->nr_regs; i++) {
		reg = &uart_regs->regs[i];

		if (NULL == reg->name)
			continue;

		if (x49gp_module_get_u32(module, key, reg->name,
					 reg->reset, reg->datap))
			error = -EAGAIN;
	}

	return error;
}

static int
s3c2410_uart_save(x49gp_module_t *module, GKeyFile *key)
{
	s3c2410_uart_reg_t *uart_regs = module->user_data;
	s3c2410_offset_t *reg;
	int i;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	for (i = 0; i < uart_regs->nr_regs; i++) {
		reg = &uart_regs->regs[i];

		if (NULL == reg->name)
			continue;

		x49gp_module_set_u32(module, key, reg->name, *(reg->datap));
	}

	return 0;
}

static int
s3c2410_uart_reset(x49gp_module_t *module, x49gp_reset_t reset)
{
	s3c2410_uart_reg_t *uart_regs = module->user_data;
	s3c2410_offset_t *reg;
	int i;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	for (i = 0; i < uart_regs->nr_regs; i++) {
		reg = &uart_regs->regs[i];

		if (NULL == reg->name)
			continue;

		*(reg->datap) = reg->reset;
	}

	return 0;
}

static CPUReadMemoryFunc *s3c2410_uart_readfn[] =
{
	s3c2410_uart_read,
	s3c2410_uart_read,
	s3c2410_uart_read
};

static CPUWriteMemoryFunc *s3c2410_uart_writefn[] =
{
	s3c2410_uart_write,
	s3c2410_uart_write,
	s3c2410_uart_write
};

static int
s3c2410_uart_init(x49gp_module_t *module)
{
	s3c2410_uart_reg_t *uart_regs = module->user_data;
	int iotype;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	iotype = cpu_register_io_memory(s3c2410_uart_readfn,
					s3c2410_uart_writefn, uart_regs);
#ifdef DEBUG_S3C2410_UART
	printf("%s: iotype %08x\n", __FUNCTION__, iotype);
#endif
	cpu_register_physical_memory(S3C2410_UART0_BASE, S3C2410_MAP_SIZE, iotype);

	return 0;
}

static int
s3c2410_uart_exit(x49gp_module_t *module)
{
	s3c2410_uart_reg_t *uart_regs;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	if (module->user_data) {
		uart_regs = module->user_data;
		if (uart_regs->regs)
			free(uart_regs->regs);
	}

	x49gp_module_unregister(module);
	free(module);

	return 0;
}

int
x49gp_s3c2410_uart_init(x49gp_t *x49gp)
{
	s3c2410_uart_t *uart;
	x49gp_module_t *module;

	uart = malloc(sizeof(s3c2410_uart_t));
	if (NULL == uart) {
		fprintf(stderr, "%s:%u: Out of memory\n",
			__FUNCTION__, __LINE__);
		return -ENOMEM;
	}
	memset(uart, 0, sizeof(s3c2410_uart_t));

	if (s3c2410_uart_data_init(uart)) {
		free(uart);
		return -ENOMEM;
	}

	uart->uart[0].x49gp = x49gp;
	uart->uart[1].x49gp = x49gp;
	uart->uart[2].x49gp = x49gp;

	if (x49gp_module_init(x49gp, "s3c2410-uart0",
			      s3c2410_uart_init,
			      s3c2410_uart_exit,
			      s3c2410_uart_reset,
			      s3c2410_uart_load,
			      s3c2410_uart_save,
			      &uart->uart[0], &module)) {
		return -1;
	}
	if (x49gp_module_register(module)) {
		return -1;
	}

	if (x49gp_module_init(x49gp, "s3c2410-uart1",
			      s3c2410_uart_init,
			      s3c2410_uart_exit,
			      s3c2410_uart_reset,
			      s3c2410_uart_load,
			      s3c2410_uart_save,
			      &uart->uart[1], &module)) {
		return -1;
	}
	if (x49gp_module_register(module)) {
		return -1;
	}

	if (x49gp_module_init(x49gp, "s3c2410-uart2",
			      s3c2410_uart_init,
			      s3c2410_uart_exit,
			      s3c2410_uart_reset,
			      s3c2410_uart_load,
			      s3c2410_uart_save,
			      &uart->uart[2], &module)) {
		return -1;
	}
	if (x49gp_module_register(module)) {
		return -1;
	}

	return 0;
}