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/export.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/seq_file.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/gfp.h>

#include <video/omapdss.h>

#include "dss.h"
#include "dss_features.h"

#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_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 int dss_runtime_get(void);
static void dss_runtime_put(void);

struct dss_features {
	u8 fck_div_max;
	u8 dss_fck_multiplier;
	const char *clk_name;
	int (*dpi_select_source)(enum omap_channel channel);
};

static struct {
	struct platform_device *pdev;
	void __iomem    *base;

	struct clk	*dpll4_m4_ck;
	struct clk	*dss_clk;

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

	enum omap_dss_clk_source dsi_clk_source[MAX_NUM_DSI];
	enum omap_dss_clk_source dispc_clk_source;
	enum omap_dss_clk_source lcd_clk_source[MAX_DSS_LCD_MANAGERS];

	bool		ctx_valid;
	u32		ctx[DSS_SZ_REGS / sizeof(u32)];

	const struct dss_features *feat;
} dss;

static const char * const dss_generic_clk_source_names[] = {
	[OMAP_DSS_CLK_SRC_DSI_PLL_HSDIV_DISPC]	= "DSI_PLL_HSDIV_DISPC",
	[OMAP_DSS_CLK_SRC_DSI_PLL_HSDIV_DSI]	= "DSI_PLL_HSDIV_DSI",
	[OMAP_DSS_CLK_SRC_FCK]			= "DSS_FCK",
};

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)])

static void dss_save_context(void)
{
	DSSDBG("dss_save_context\n");

	SR(CONTROL);

	if (dss_feat_get_supported_displays(OMAP_DSS_CHANNEL_LCD) &
			OMAP_DISPLAY_TYPE_SDI) {
		SR(SDI_CONTROL);
		SR(PLL_CONTROL);
	}

	dss.ctx_valid = true;

	DSSDBG("context saved\n");
}

static void dss_restore_context(void)
{
	DSSDBG("dss_restore_context\n");

	if (!dss.ctx_valid)
		return;

	RR(CONTROL);

	if (dss_feat_get_supported_displays(OMAP_DSS_CHANNEL_LCD) &
			OMAP_DISPLAY_TYPE_SDI) {
		RR(SDI_CONTROL);
		RR(PLL_CONTROL);
	}

	DSSDBG("context restored\n");
}

#undef SR
#undef RR

void dss_sdi_init(int 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 P