OMAP: add TI OMAP1 external LCD controller support - SoSSI

- Adds support for Texas Instruments OMAP1 processors boards connected with
  external LCD controller through "Special OptimiSed Screen Interface"

Signed-off-by: Trilok Soni <soni.trilok@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/omap/sossi.c b/drivers/video/omap/sossi.c
new file mode 100644
index 0000000..81dbcf5
--- /dev/null
+++ b/drivers/video/omap/sossi.c
@@ -0,0 +1,686 @@
+/*
+ * OMAP1 Special OptimiSed Screen Interface support
+ *
+ * Copyright (C) 2004-2005 Nokia Corporation
+ * Author: Juha Yrjölä <juha.yrjola@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * 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, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/clk.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include <asm/arch/dma.h>
+#include <asm/arch/omapfb.h>
+
+#include "lcdc.h"
+
+#define MODULE_NAME		"omapfb-sossi"
+
+#define OMAP_SOSSI_BASE         0xfffbac00
+#define SOSSI_ID_REG		0x00
+#define SOSSI_INIT1_REG		0x04
+#define SOSSI_INIT2_REG		0x08
+#define SOSSI_INIT3_REG		0x0c
+#define SOSSI_FIFO_REG		0x10
+#define SOSSI_REOTABLE_REG	0x14
+#define SOSSI_TEARING_REG	0x18
+#define SOSSI_INIT1B_REG	0x1c
+#define SOSSI_FIFOB_REG		0x20
+
+#define DMA_GSCR          0xfffedc04
+#define DMA_LCD_CCR       0xfffee3c2
+#define DMA_LCD_CTRL      0xfffee3c4
+#define DMA_LCD_LCH_CTRL  0xfffee3ea
+
+#define CONF_SOSSI_RESET_R      (1 << 23)
+
+#define RD_ACCESS		0
+#define WR_ACCESS		1
+
+#define SOSSI_MAX_XMIT_BYTES	(512 * 1024)
+
+static struct {
+	void __iomem	*base;
+	struct clk	*fck;
+	unsigned long	fck_hz;
+	spinlock_t	lock;
+	int		bus_pick_count;
+	int		bus_pick_width;
+	int		tearsync_mode;
+	int		tearsync_line;
+	void		(*lcdc_callback)(void *data);
+	void		*lcdc_callback_data;
+	int		vsync_dma_pending;
+	/* timing for read and write access */
+	int		clk_div;
+	u8		clk_tw0[2];
+	u8		clk_tw1[2];
+	/*
+	 * if last_access is the same as current we don't have to change
+	 * the timings
+	 */
+	int		last_access;
+
+	struct omapfb_device	*fbdev;
+} sossi;
+
+static inline u32 sossi_read_reg(int reg)
+{
+	return readl(sossi.base + reg);
+}
+
+static inline u16 sossi_read_reg16(int reg)
+{
+	return readw(sossi.base + reg);
+}
+
+static inline u8 sossi_read_reg8(int reg)
+{
+	return readb(sossi.base + reg);
+}
+
+static inline void sossi_write_reg(int reg, u32 value)
+{
+	writel(value, sossi.base + reg);
+}
+
+static inline void sossi_write_reg16(int reg, u16 value)
+{
+	writew(value, sossi.base + reg);
+}
+
+static inline void sossi_write_reg8(int reg, u8 value)
+{
+	writeb(value, sossi.base + reg);
+}
+
+static void sossi_set_bits(int reg, u32 bits)
+{
+	sossi_write_reg(reg, sossi_read_reg(reg) | bits);
+}
+
+static void sossi_clear_bits(int reg, u32 bits)
+{
+	sossi_write_reg(reg, sossi_read_reg(reg) & ~bits);
+}
+
+#define HZ_TO_PS(x)	(1000000000 / (x / 1000))
+
+static u32 ps_to_sossi_ticks(u32 ps, int div)
+{
+	u32 clk_period = HZ_TO_PS(sossi.fck_hz) * div;
+	return (clk_period + ps - 1) / clk_period;
+}
+
+static int calc_rd_timings(struct extif_timings *t)
+{
+	u32 tw0, tw1;
+	int reon, reoff, recyc, actim;
+	int div = t->clk_div;
+
+	/*
+	 * Make sure that after conversion it still holds that:
+	 * reoff > reon, recyc >= reoff, actim > reon
+	 */
+	reon = ps_to_sossi_ticks(t->re_on_time, div);
+	/* reon will be exactly one sossi tick */
+	if (reon > 1)
+		return -1;
+
+	reoff = ps_to_sossi_ticks(t->re_off_time, div);
+
+	if (reoff <= reon)
+		reoff = reon + 1;
+
+	tw0 = reoff - reon;
+	if (tw0 > 0x10)
+		return -1;
+
+	recyc = ps_to_sossi_ticks(t->re_cycle_time, div);
+	if (recyc <= reoff)
+		recyc = reoff + 1;
+
+	tw1 = recyc - tw0;
+	/* values less then 3 result in the SOSSI block resetting itself */
+	if (tw1 < 3)
+		tw1 = 3;
+	if (tw1 > 0x40)
+		return -1;
+
+	actim = ps_to_sossi_ticks(t->access_time, div);
+	if (actim < reoff)
+		actim++;
+	/*
+	 * access time (data hold time) will be exactly one sossi
+	 * tick
+	 */
+	if (actim - reoff > 1)
+		return -1;
+
+	t->tim[0] = tw0 - 1;
+	t->tim[1] = tw1 - 1;
+
+	return 0;
+}
+
+static int calc_wr_timings(struct extif_timings *t)
+{
+	u32 tw0, tw1;
+	int weon, weoff, wecyc;
+	int div = t->clk_div;
+
+	/*
+	 * Make sure that after conversion it still holds that:
+	 * weoff > weon, wecyc >= weoff
+	 */
+	weon = ps_to_sossi_ticks(t->we_on_time, div);
+	/* weon will be exactly one sossi tick */
+	if (weon > 1)
+		return -1;
+
+	weoff = ps_to_sossi_ticks(t->we_off_time, div);
+	if (weoff <= weon)
+		weoff = weon + 1;
+	tw0 = weoff - weon;
+	if (tw0 > 0x10)
+		return -1;
+
+	wecyc = ps_to_sossi_ticks(t->we_cycle_time, div);
+	if (wecyc <= weoff)
+		wecyc = weoff + 1;
+
+	tw1 = wecyc - tw0;
+	/* values less then 3 result in the SOSSI block resetting itself */
+	if (tw1 < 3)
+		tw1 = 3;
+	if (tw1 > 0x40)
+		return -1;
+
+	t->tim[2] = tw0 - 1;
+	t->tim[3] = tw1 - 1;
+
+	return 0;
+}
+
+static void _set_timing(int div, int tw0, int tw1)
+{
+	u32 l;
+
+#ifdef VERBOSE
+	dev_dbg(sossi.fbdev->dev, "Using TW0 = %d, TW1 = %d, div = %d\n",
+		 tw0 + 1, tw1 + 1, div);
+#endif
+
+	clk_set_rate(sossi.fck, sossi.fck_hz / div);
+	clk_enable(sossi.fck);
+	l = sossi_read_reg(SOSSI_INIT1_REG);
+	l &= ~((0x0f << 20) | (0x3f << 24));
+	l |= (tw0 << 20) | (tw1 << 24);
+	sossi_write_reg(SOSSI_INIT1_REG, l);
+	clk_disable(sossi.fck);
+}
+
+static void _set_bits_per_cycle(int bus_pick_count, int bus_pick_width)
+{
+	u32 l;
+
+	l = sossi_read_reg(SOSSI_INIT3_REG);
+	l &= ~0x3ff;
+	l |= ((bus_pick_count - 1) << 5) | ((bus_pick_width - 1) & 0x1f);
+	sossi_write_reg(SOSSI_INIT3_REG, l);
+}
+
+static void _set_tearsync_mode(int mode, unsigned line)
+{
+	u32 l;
+
+	l = sossi_read_reg(SOSSI_TEARING_REG);
+	l &= ~(((1 << 11) - 1) << 15);
+	l |= line << 15;
+	l &= ~(0x3 << 26);
+	l |= mode << 26;
+	sossi_write_reg(SOSSI_TEARING_REG, l);
+	if (mode)
+		sossi_set_bits(SOSSI_INIT2_REG, 1 << 6);	/* TE logic */
+	else
+		sossi_clear_bits(SOSSI_INIT2_REG, 1 << 6);
+}
+
+static inline void set_timing(int access)
+{
+	if (access != sossi.last_access) {
+		sossi.last_access = access;
+		_set_timing(sossi.clk_div,
+			    sossi.clk_tw0[access], sossi.clk_tw1[access]);
+	}
+}
+
+static void sossi_start_transfer(void)
+{
+	/* WE */
+	sossi_clear_bits(SOSSI_INIT2_REG, 1 << 4);
+	/* CS active low */
+	sossi_clear_bits(SOSSI_INIT1_REG, 1 << 30);
+}
+
+static void sossi_stop_transfer(void)
+{
+	/* WE */
+	sossi_set_bits(SOSSI_INIT2_REG, 1 << 4);
+	/* CS active low */
+	sossi_set_bits(SOSSI_INIT1_REG, 1 << 30);
+}
+
+static void wait_end_of_write(void)
+{
+	/* Before reading we must check if some writings are going on */
+	while (!(sossi_read_reg(SOSSI_INIT2_REG) & (1 << 3)));
+}
+
+static void send_data(const void *data, unsigned int len)
+{
+	while (len >= 4) {
+		sossi_write_reg(SOSSI_FIFO_REG, *(const u32 *) data);
+		len -= 4;
+		data += 4;
+	}
+	while (len >= 2) {
+		sossi_write_reg16(SOSSI_FIFO_REG, *(const u16 *) data);
+		len -= 2;
+		data += 2;
+	}
+	while (len) {
+		sossi_write_reg8(SOSSI_FIFO_REG, *(const u8 *) data);
+		len--;
+		data++;
+	}
+}
+
+static void set_cycles(unsigned int len)
+{
+	unsigned long nr_cycles = len / (sossi.bus_pick_width / 8);
+
+	BUG_ON((nr_cycles - 1) & ~0x3ffff);
+
+	sossi_clear_bits(SOSSI_INIT1_REG, 0x3ffff);
+	sossi_set_bits(SOSSI_INIT1_REG, (nr_cycles - 1) & 0x3ffff);
+}
+
+static int sossi_convert_timings(struct extif_timings *t)
+{
+	int r = 0;
+	int div = t->clk_div;
+
+	t->converted = 0;
+
+	if (div <= 0 || div > 8)
+		return -1;
+
+	/* no CS on SOSSI, so ignore cson, csoff, cs_pulsewidth */
+	if ((r = calc_rd_timings(t)) < 0)
+		return r;
+
+	if ((r = calc_wr_timings(t)) < 0)
+		return r;
+
+	t->tim[4] = div;
+
+	t->converted = 1;
+
+	return 0;
+}
+
+static void sossi_set_timings(const struct extif_timings *t)
+{
+	BUG_ON(!t->converted);
+
+	sossi.clk_tw0[RD_ACCESS] = t->tim[0];
+	sossi.clk_tw1[RD_ACCESS] = t->tim[1];
+
+	sossi.clk_tw0[WR_ACCESS] = t->tim[2];
+	sossi.clk_tw1[WR_ACCESS] = t->tim[3];
+
+	sossi.clk_div = t->tim[4];
+}
+
+static void sossi_get_clk_info(u32 *clk_period, u32 *max_clk_div)
+{
+	*clk_period = HZ_TO_PS(sossi.fck_hz);
+	*max_clk_div = 8;
+}
+
+static void sossi_set_bits_per_cycle(int bpc)
+{
+	int bus_pick_count, bus_pick_width;
+
+	/*
+	 * We set explicitly the the bus_pick_count as well, although
+	 * with remapping/reordering disabled it will be calculated by HW
+	 * as (32 / bus_pick_width).
+	 */
+	switch (bpc) {
+	case 8:
+		bus_pick_count = 4;
+		bus_pick_width = 8;
+		break;
+	case 16:
+		bus_pick_count = 2;
+		bus_pick_width = 16;
+		break;
+	default:
+		BUG();
+		return;
+	}
+	sossi.bus_pick_width = bus_pick_width;
+	sossi.bus_pick_count = bus_pick_count;
+}
+
+static int sossi_setup_tearsync(unsigned pin_cnt,
+				unsigned hs_pulse_time, unsigned vs_pulse_time,
+				int hs_pol_inv, int vs_pol_inv, int div)
+{
+	int hs, vs;
+	u32 l;
+
+	if (pin_cnt != 1 || div < 1 || div > 8)
+		return -EINVAL;
+
+	hs = ps_to_sossi_ticks(hs_pulse_time, div);
+	vs = ps_to_sossi_ticks(vs_pulse_time, div);
+	if (vs < 8 || vs <= hs || vs >= (1 << 12))
+		return -EDOM;
+	vs /= 8;
+	vs--;
+	if (hs > 8)
+		hs = 8;
+	if (hs)
+		hs--;
+
+	dev_dbg(sossi.fbdev->dev,
+		"setup_tearsync: hs %d vs %d hs_inv %d vs_inv %d\n",
+		hs, vs, hs_pol_inv, vs_pol_inv);
+
+	clk_enable(sossi.fck);
+	l = sossi_read_reg(SOSSI_TEARING_REG);
+	l &= ~((1 << 15) - 1);
+	l |= vs << 3;
+	l |= hs;
+	if (hs_pol_inv)
+		l |= 1 << 29;
+	else
+		l &= ~(1 << 29);
+	if (vs_pol_inv)
+		l |= 1 << 28;
+	else
+		l &= ~(1 << 28);
+	sossi_write_reg(SOSSI_TEARING_REG, l);
+	clk_disable(sossi.fck);
+
+	return 0;
+}
+
+static int sossi_enable_tearsync(int enable, unsigned line)
+{
+	int mode;
+
+	dev_dbg(sossi.fbdev->dev, "tearsync %d line %d\n", enable, line);
+	if (line >= 1 << 11)
+		return -EINVAL;
+	if (enable) {
+		if (line)
+			mode = 2;		/* HS or VS */
+		else
+			mode = 3;		/* VS only */
+	} else
+		mode = 0;
+	sossi.tearsync_line = line;
+	sossi.tearsync_mode = mode;
+
+	return 0;
+}
+
+static void sossi_write_command(const void *data, unsigned int len)
+{
+	clk_enable(sossi.fck);
+	set_timing(WR_ACCESS);
+	_set_bits_per_cycle(sossi.bus_pick_count, sossi.bus_pick_width);
+	/* CMD#/DATA */
+	sossi_clear_bits(SOSSI_INIT1_REG, 1 << 18);
+	set_cycles(len);
+	sossi_start_transfer();
+	send_data(data, len);
+	sossi_stop_transfer();
+	wait_end_of_write();
+	clk_disable(sossi.fck);
+}
+
+static void sossi_write_data(const void *data, unsigned int len)
+{
+	clk_enable(sossi.fck);
+	set_timing(WR_ACCESS);
+	_set_bits_per_cycle(sossi.bus_pick_count, sossi.bus_pick_width);
+	/* CMD#/DATA */
+	sossi_set_bits(SOSSI_INIT1_REG, 1 << 18);
+	set_cycles(len);
+	sossi_start_transfer();
+	send_data(data, len);
+	sossi_stop_transfer();
+	wait_end_of_write();
+	clk_disable(sossi.fck);
+}
+
+static void sossi_transfer_area(int width, int height,
+				void (callback)(void *data), void *data)
+{
+	BUG_ON(callback == NULL);
+
+	sossi.lcdc_callback = callback;
+	sossi.lcdc_callback_data = data;
+
+	clk_enable(sossi.fck);
+	set_timing(WR_ACCESS);
+	_set_bits_per_cycle(sossi.bus_pick_count, sossi.bus_pick_width);
+	_set_tearsync_mode(sossi.tearsync_mode, sossi.tearsync_line);
+	/* CMD#/DATA */
+	sossi_set_bits(SOSSI_INIT1_REG, 1 << 18);
+	set_cycles(width * height * sossi.bus_pick_width / 8);
+
+	sossi_start_transfer();
+	if (sossi.tearsync_mode) {
+		/*
+		 * Wait for the sync signal and start the transfer only
+		 * then. We can't seem to be able to use HW sync DMA for
+		 * this since LCD DMA shows huge latencies, as if it
+		 * would ignore some of the DMA requests from SoSSI.
+		 */
+		unsigned long flags;
+
+		spin_lock_irqsave(&sossi.lock, flags);
+		sossi.vsync_dma_pending++;
+		spin_unlock_irqrestore(&sossi.lock, flags);
+	} else
+		/* Just start the transfer right away. */
+		omap_enable_lcd_dma();
+}
+
+static void sossi_dma_callback(void *data)
+{
+	omap_stop_lcd_dma();
+	sossi_stop_transfer();
+	clk_disable(sossi.fck);
+	sossi.lcdc_callback(sossi.lcdc_callback_data);
+}
+
+static void sossi_read_data(void *data, unsigned int len)
+{
+	clk_enable(sossi.fck);
+	set_timing(RD_ACCESS);
+	_set_bits_per_cycle(sossi.bus_pick_count, sossi.bus_pick_width);
+	/* CMD#/DATA */
+	sossi_set_bits(SOSSI_INIT1_REG, 1 << 18);
+	set_cycles(len);
+	sossi_start_transfer();
+	while (len >= 4) {
+		*(u32 *) data = sossi_read_reg(SOSSI_FIFO_REG);
+		len -= 4;
+		data += 4;
+	}
+	while (len >= 2) {
+		*(u16 *) data = sossi_read_reg16(SOSSI_FIFO_REG);
+		len -= 2;
+		data += 2;
+	}
+	while (len) {
+		*(u8 *) data = sossi_read_reg8(SOSSI_FIFO_REG);
+		len--;
+		data++;
+	}
+	sossi_stop_transfer();
+	clk_disable(sossi.fck);
+}
+
+static irqreturn_t sossi_match_irq(int irq, void *data)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sossi.lock, flags);
+	if (sossi.vsync_dma_pending) {
+		sossi.vsync_dma_pending--;
+		omap_enable_lcd_dma();
+	}
+	spin_unlock_irqrestore(&sossi.lock, flags);
+	return IRQ_HANDLED;
+}
+
+static int sossi_init(struct omapfb_device *fbdev)
+{
+	u32 l, k;
+	struct clk *fck;
+	struct clk *dpll1out_ck;
+	int r;
+
+	sossi.base = (void __iomem *)IO_ADDRESS(OMAP_SOSSI_BASE);
+	sossi.fbdev = fbdev;
+	spin_lock_init(&sossi.lock);
+
+	dpll1out_ck = clk_get(fbdev->dev, "ck_dpll1out");
+	if (IS_ERR(dpll1out_ck)) {
+		dev_err(fbdev->dev, "can't get DPLL1OUT clock\n");
+		return PTR_ERR(dpll1out_ck);
+	}
+	/*
+	 * We need the parent clock rate, which we might divide further
+	 * depending on the timing requirements of the controller. See
+	 * _set_timings.
+	 */
+	sossi.fck_hz = clk_get_rate(dpll1out_ck);
+	clk_put(dpll1out_ck);
+
+	fck = clk_get(fbdev->dev, "ck_sossi");
+	if (IS_ERR(fck)) {
+		dev_err(fbdev->dev, "can't get SoSSI functional clock\n");
+		return PTR_ERR(fck);
+	}
+	sossi.fck = fck;
+
+	/* Reset and enable the SoSSI module */
+	l = omap_readl(MOD_CONF_CTRL_1);
+	l |= CONF_SOSSI_RESET_R;
+	omap_writel(l, MOD_CONF_CTRL_1);
+	l &= ~CONF_SOSSI_RESET_R;
+	omap_writel(l, MOD_CONF_CTRL_1);
+
+	clk_enable(sossi.fck);
+	l = omap_readl(ARM_IDLECT2);
+	l &= ~(1 << 8);			/* DMACK_REQ */
+	omap_writel(l, ARM_IDLECT2);
+
+	l = sossi_read_reg(SOSSI_INIT2_REG);
+	/* Enable and reset the SoSSI block */
+	l |= (1 << 0) | (1 << 1);
+	sossi_write_reg(SOSSI_INIT2_REG, l);
+	/* Take SoSSI out of reset */
+	l &= ~(1 << 1);
+	sossi_write_reg(SOSSI_INIT2_REG, l);
+
+	sossi_write_reg(SOSSI_ID_REG, 0);
+	l = sossi_read_reg(SOSSI_ID_REG);
+	k = sossi_read_reg(SOSSI_ID_REG);
+
+	if (l != 0x55555555 || k != 0xaaaaaaaa) {
+		dev_err(fbdev->dev,
+			"invalid SoSSI sync pattern: %08x, %08x\n", l, k);
+		r = -ENODEV;
+		goto err;
+	}
+
+	if ((r = omap_lcdc_set_dma_callback(sossi_dma_callback, NULL)) < 0) {
+		dev_err(fbdev->dev, "can't get LCDC IRQ\n");
+		r = -ENODEV;
+		goto err;
+	}
+
+	l = sossi_read_reg(SOSSI_ID_REG); /* Component code */
+	l = sossi_read_reg(SOSSI_ID_REG);
+	dev_info(fbdev->dev, "SoSSI version %d.%d initialized\n",
+		l >> 16, l & 0xffff);
+
+	l = sossi_read_reg(SOSSI_INIT1_REG);
+	l |= (1 << 19); /* DMA_MODE */
+	l &= ~(1 << 31); /* REORDERING */
+	sossi_write_reg(SOSSI_INIT1_REG, l);
+
+	if ((r = request_irq(INT_1610_SoSSI_MATCH, sossi_match_irq,
+			     IRQT_FALLING,
+	     "sossi_match", sossi.fbdev->dev)) < 0) {
+		dev_err(sossi.fbdev->dev, "can't get SoSSI match IRQ\n");
+		goto err;
+	}
+
+	clk_disable(sossi.fck);
+	return 0;
+
+err:
+	clk_disable(sossi.fck);
+	clk_put(sossi.fck);
+	return r;
+}
+
+static void sossi_cleanup(void)
+{
+	omap_lcdc_free_dma_callback();
+	clk_put(sossi.fck);
+}
+
+struct lcd_ctrl_extif omap1_ext_if = {
+	.init			= sossi_init,
+	.cleanup		= sossi_cleanup,
+	.get_clk_info		= sossi_get_clk_info,
+	.convert_timings	= sossi_convert_timings,
+	.set_timings		= sossi_set_timings,
+	.set_bits_per_cycle	= sossi_set_bits_per_cycle,
+	.setup_tearsync		= sossi_setup_tearsync,
+	.enable_tearsync	= sossi_enable_tearsync,
+	.write_command		= sossi_write_command,
+	.read_data		= sossi_read_data,
+	.write_data		= sossi_write_data,
+	.transfer_area		= sossi_transfer_area,
+
+	.max_transmit_size	= SOSSI_MAX_XMIT_BYTES,
+};
+