path: root/drivers/video/omap2/dss/dss.c

/*
 * linux/drivers/video/omap2/dss/dss.c
 *
 * Copyright (C) 2009 Nokia Corporation
 * Author: Tomi Valkeinen <tomi.valkeinen@nokia.com>
 *
 * Some code and ideas taken from drivers/video/omap/ driver
 * by Imre Deak.
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#define DSS_SUBSYS_NAME "DSS"

#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/seq_file.h>
#include <linux/clk.h>

#include <plat/display.h>
#include "dss.h"

#define DSS_BASE			0x48050000

#define DSS_SZ_REGS			SZ_512

struct dss_reg {
	u16 idx;
};

#define DSS_REG(idx)			((const struct dss_reg) { idx })

#define DSS_REVISION			DSS_REG(0x0000)
#define DSS_SYSCONFIG			DSS_REG(0x0010)
#define DSS_SYSSTATUS			DSS_REG(0x0014)
#define DSS_IRQSTATUS			DSS_REG(0x0018)
#define DSS_CONTROL			DSS_REG(0x0040)
#define DSS_SDI_CONTROL			DSS_REG(0x0044)
#define DSS_PLL_CONTROL			DSS_REG(0x0048)
#define DSS_SDI_STATUS			DSS_REG(0x005C)

#define REG_GET(idx, start, end) \
	FLD_GET(dss_read_reg(idx), start, end)

#define REG_FLD_MOD(idx, val, start, end) \
	dss_write_reg(idx, FLD_MOD(dss_read_reg(idx), val, start, end))

static struct {
	void __iomem    *base;

	struct clk	*dpll4_m4_ck;

	unsigned long	cache_req_pck;
	unsigned long	cache_prate;
	struct dss_clock_info cache_dss_cinfo;
	struct dispc_clock_info cache_dispc_cinfo;

	enum dss_clk_source dsi_clk_source;
	enum dss_clk_source dispc_clk_source;

	u32		ctx[DSS_SZ_REGS / sizeof(u32)];
} dss;

static int _omap_dss_wait_reset(void);

static inline void dss_write_reg(const struct dss_reg idx, u32 val)
{
	__raw_writel(val, dss.base + idx.idx);
}

static inline u32 dss_read_reg(const struct dss_reg idx)
{
	return __raw_readl(dss.base + idx.idx);
}

#define SR(reg) \
	dss.ctx[(DSS_##reg).idx / sizeof(u32)] = dss_read_reg(DSS_##reg)
#define RR(reg) \
	dss_write_reg(DSS_##reg, dss.ctx[(DSS_##reg).idx / sizeof(u32)])

void dss_save_context(void)
{
	if (cpu_is_omap24xx())
		return;

	SR(SYSCONFIG);
	SR(CONTROL);

#ifdef CONFIG_OMAP2_DSS_SDI
	SR(SDI_CONTROL);
	SR(PLL_CONTROL);
#endif
}

void dss_restore_context(void)
{
	if (_omap_dss_wait_reset())
		DSSERR("DSS not coming out of reset after sleep\n");

	RR(SYSCONFIG);
	RR(CONTROL);

#ifdef CONFIG_OMAP2_DSS_SDI
	RR(SDI_CONTROL);
	RR(PLL_CONTROL);
#endif
}

#undef SR
#undef RR

void dss_sdi_init(u8 datapairs)
{
	u32 l;

	BUG_ON(datapairs > 3 || datapairs < 1);

	l = dss_read_reg(DSS_SDI_CONTROL);
	l = FLD_MOD(l, 0xf, 19, 15);		/* SDI_PDIV */
	l = FLD_MOD(l, datapairs-1, 3, 2);	/* SDI_PRSEL */
	l = FLD_MOD(l, 2, 1, 0);		/* SDI_BWSEL */
	dss_write_reg(DSS_SDI_CONTROL, l);

	l = dss_read_reg(DSS_PLL_CONTROL);
	l = FLD_MOD(l, 0x7, 25, 22);	/* SDI_PLL_FREQSEL */
	l = FLD_MOD(l, 0xb, 16, 11);	/* SDI_PLL_REGN */
	l = FLD_MOD(l, 0xb4, 10, 1);	/* SDI_PLL_REGM */
	dss_write_reg(DSS_PLL_CONTROL, l);
}

int dss_sdi_enable(void)
{
	unsigned long timeout;

	dispc_pck_free_enable(1);

	/* Reset SDI PLL */
	REG_FLD_MOD(DSS_PLL_CONTROL, 1, 18, 18); /* SDI_PLL_SYSRESET */
	udelay(1);	/* wait 2x PCLK */

	/* Lock SDI PLL */
	REG_FLD_MOD(DSS_PLL_CONTROL, 1, 28, 28); /* SDI_PLL_GOBIT */

	/* Waiting for PLL lock request to complete */
	timeout = jiffies + msecs_to_jiffies(500);
	while (dss_read_reg(DSS_SDI_STATUS) & (1 << 6)) {
		if (time_after_eq(jiffies, timeout)) {
			DSSERR("PLL lock request timed out\n");
			goto err1;
		}
	}

	/* Clearing PLL_GO bit */
	REG_FLD_MOD(DSS_PLL_CONTROL, 0, 28, 28);

	/* Waiting for PLL to lock */
	timeout = jiffies + msecs_to_jiffies(500);
	while (!(dss_read_reg(DSS_SDI_STATUS) & (1 << 5))) {
		if (time_after_eq(jiffies, timeout)) {
			DSSERR("PLL lock timed out\n");
			goto err1;
		}
	}

	dispc_lcd_enable_signal(1);

	/* Waiting for SDI reset to complete */
	timeout = jiffies + msecs_to_jiffies(500);
	while (!(dss_read_reg(DSS_SDI_STATUS) & (1 << 2))) {
		if (time_after_eq(jiffies, timeout)) {
			DSSERR("SDI reset timed out\n");
			goto err2;
		}
	}

	return 0;

 err2:
	dispc_lcd_enable_signal(0);
 err1:
	/* Reset SDI PLL */
	REG_FLD_MOD(DSS_PLL_CONTROL, 0, 18, 18); /* SDI_PLL_SYSRESET */

	dispc_pck_free_enable(0);

	return -ETIMEDOUT;
}

void dss_sdi_disable(void)
{
	dispc_lcd_enable_signal(0);

	dispc_pck_free_enable(0);

	/* Reset SDI PLL */
	REG_FLD_MOD(DSS_PLL_CONTROL, 0, 18, 18); /* SDI_PLL_SYSRESET */
}

void dss_dump_clocks(struct seq_file *s)
{
	unsigned long dpll4_ck_rate;
	unsigned long dpll4_m4_ck_rate;

	dss_clk_enable(DSS_CLK_ICK | DSS_CLK_FCK1);

	dpll4_ck_rate = clk_get_rate(clk_get_parent(dss.dpll4_m4_ck));
	dpll4_m4_ck_rate = clk_get_rate(dss.dpll4_m4_ck);

	seq_printf(s, "- DSS -\n");

	seq_printf(s, "dpll4_ck %lu\n", dpll4_ck_rate);

	seq_printf(s, "dss1_alwon_fclk = %lu / %lu * 2 = %lu\n",
			dpll4_ck_rate,
			dpll4_ck_rate / dpll4_m4_ck_rate,
			dss_clk_get_rate(DSS_CLK_FCK1));

	dss_clk_disable(DSS_CLK_ICK | DSS_CLK_FCK1);
}

void dss_dump_regs(struct seq_file *s)
{
#define DUMPREG(r) seq_printf(s, "%-35s %08x\n", #r, dss_read_reg(r))

	dss_clk_enable(DSS_CLK_ICK | DSS_CLK_FCK1);

	DUMPREG(DSS_REVISION);
	DUMPREG(DSS_SYSCONFIG);
	DUMPREG(DSS_SYSSTATUS);
	DUMPREG(DSS_IRQSTATUS);
	DUMPREG(DSS_CONTROL);
	DUMPREG(DSS_SDI_CONTROL);
	DUMPREG(DSS_PLL_CONTROL);
	DUMPREG(DSS_SDI_STATUS);

	dss_clk_disable(DSS_CLK_ICK | DSS_CLK_FCK1);
#undef DUMPREG
}

void dss_select_dispc_clk_source(enum dss_clk_source clk_src)
{
	int b;

	BUG_ON(clk_src != DSS_SRC_DSI1_PLL_FCLK &&
			clk_src != DSS_SRC_DSS1_ALWON_FCLK);

	b = clk_src == DSS_SRC_DSS1_ALWON_FCLK ? 0 : 1;

	REG_FLD_MOD(DSS_CONTROL, b, 0, 0);	/* DISPC_CLK_SWITCH */

	dss.dispc_clk_source = clk_src;
}

void dss_select_dsi_clk_source(enum dss_clk_source clk_src)
{
	int b;

	BUG_ON(clk_src != DSS_SRC_DSI2_PLL_FCLK &&
			clk_src != DSS_SRC_DSS1_ALWON_FCLK);

	b = clk_src == DSS_SRC_DSS1_ALWON_FCLK ? 0 : 1;

	REG_FLD_MOD(DSS_CONTROL, b, 1, 1);	/* DSI_CLK_SWITCH */

	dss.dsi_clk_source = clk_src;
}

enum dss_clk_source dss_get_dispc_clk_source(void)
{
	return dss.dispc_clk_source;
}

enum dss_clk_source dss_get_dsi_clk_source(void)
{
	return dss.dsi_clk_source;
}

/* calculate cl