Linux Audio

Check our new training course

Loading...
Note: File does not exist in v4.6.
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Copyright (C) 2016 Marek Vasut <marex@denx.de>
  4 *
  5 * This code is based on drivers/video/fbdev/mxsfb.c :
  6 * Copyright (C) 2010 Juergen Beisert, Pengutronix
  7 * Copyright (C) 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved.
  8 * Copyright (C) 2008 Embedded Alley Solutions, Inc All Rights Reserved.
  9 */
 10
 11#include <linux/clk.h>
 12#include <linux/iopoll.h>
 13#include <linux/of_graph.h>
 14#include <linux/platform_data/simplefb.h>
 15
 16#include <video/videomode.h>
 17
 18#include <drm/drm_atomic_helper.h>
 19#include <drm/drm_crtc.h>
 20#include <drm/drm_fb_cma_helper.h>
 21#include <drm/drm_fb_helper.h>
 22#include <drm/drm_gem_cma_helper.h>
 23#include <drm/drm_of.h>
 24#include <drm/drm_plane_helper.h>
 25#include <drm/drm_probe_helper.h>
 26#include <drm/drm_simple_kms_helper.h>
 27#include <drm/drm_vblank.h>
 28
 29#include "mxsfb_drv.h"
 30#include "mxsfb_regs.h"
 31
 32#define MXS_SET_ADDR		0x4
 33#define MXS_CLR_ADDR		0x8
 34#define MODULE_CLKGATE		BIT(30)
 35#define MODULE_SFTRST		BIT(31)
 36/* 1 second delay should be plenty of time for block reset */
 37#define RESET_TIMEOUT		1000000
 38
 39static u32 set_hsync_pulse_width(struct mxsfb_drm_private *mxsfb, u32 val)
 40{
 41	return (val & mxsfb->devdata->hs_wdth_mask) <<
 42		mxsfb->devdata->hs_wdth_shift;
 43}
 44
 45/* Setup the MXSFB registers for decoding the pixels out of the framebuffer */
 46static int mxsfb_set_pixel_fmt(struct mxsfb_drm_private *mxsfb)
 47{
 48	struct drm_crtc *crtc = &mxsfb->pipe.crtc;
 49	struct drm_device *drm = crtc->dev;
 50	const u32 format = crtc->primary->state->fb->format->format;
 51	u32 ctrl, ctrl1;
 52
 53	ctrl = CTRL_BYPASS_COUNT | CTRL_MASTER;
 54
 55	/*
 56	 * WARNING: The bus width, CTRL_SET_BUS_WIDTH(), is configured to
 57	 * match the selected mode here. This differs from the original
 58	 * MXSFB driver, which had the option to configure the bus width
 59	 * to arbitrary value. This limitation should not pose an issue.
 60	 */
 61
 62	/* CTRL1 contains IRQ config and status bits, preserve those. */
 63	ctrl1 = readl(mxsfb->base + LCDC_CTRL1);
 64	ctrl1 &= CTRL1_CUR_FRAME_DONE_IRQ_EN | CTRL1_CUR_FRAME_DONE_IRQ;
 65
 66	switch (format) {
 67	case DRM_FORMAT_RGB565:
 68		dev_dbg(drm->dev, "Setting up RGB565 mode\n");
 69		ctrl |= CTRL_SET_WORD_LENGTH(0);
 70		ctrl1 |= CTRL1_SET_BYTE_PACKAGING(0xf);
 71		break;
 72	case DRM_FORMAT_XRGB8888:
 73		dev_dbg(drm->dev, "Setting up XRGB8888 mode\n");
 74		ctrl |= CTRL_SET_WORD_LENGTH(3);
 75		/* Do not use packed pixels = one pixel per word instead. */
 76		ctrl1 |= CTRL1_SET_BYTE_PACKAGING(0x7);
 77		break;
 78	default:
 79		dev_err(drm->dev, "Unhandled pixel format %08x\n", format);
 80		return -EINVAL;
 81	}
 82
 83	writel(ctrl1, mxsfb->base + LCDC_CTRL1);
 84	writel(ctrl, mxsfb->base + LCDC_CTRL);
 85
 86	return 0;
 87}
 88
 89static void mxsfb_set_bus_fmt(struct mxsfb_drm_private *mxsfb)
 90{
 91	struct drm_crtc *crtc = &mxsfb->pipe.crtc;
 92	struct drm_device *drm = crtc->dev;
 93	u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
 94	u32 reg;
 95
 96	reg = readl(mxsfb->base + LCDC_CTRL);
 97
 98	if (mxsfb->connector.display_info.num_bus_formats)
 99		bus_format = mxsfb->connector.display_info.bus_formats[0];
100
101	reg &= ~CTRL_BUS_WIDTH_MASK;
102	switch (bus_format) {
103	case MEDIA_BUS_FMT_RGB565_1X16:
104		reg |= CTRL_SET_BUS_WIDTH(STMLCDIF_16BIT);
105		break;
106	case MEDIA_BUS_FMT_RGB666_1X18:
107		reg |= CTRL_SET_BUS_WIDTH(STMLCDIF_18BIT);
108		break;
109	case MEDIA_BUS_FMT_RGB888_1X24:
110		reg |= CTRL_SET_BUS_WIDTH(STMLCDIF_24BIT);
111		break;
112	default:
113		dev_err(drm->dev, "Unknown media bus format %d\n", bus_format);
114		break;
115	}
116	writel(reg, mxsfb->base + LCDC_CTRL);
117}
118
119static void mxsfb_enable_controller(struct mxsfb_drm_private *mxsfb)
120{
121	u32 reg;
122
123	if (mxsfb->clk_disp_axi)
124		clk_prepare_enable(mxsfb->clk_disp_axi);
125	clk_prepare_enable(mxsfb->clk);
126
127	/* If it was disabled, re-enable the mode again */
128	writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_SET);
129
130	/* Enable the SYNC signals first, then the DMA engine */
131	reg = readl(mxsfb->base + LCDC_VDCTRL4);
132	reg |= VDCTRL4_SYNC_SIGNALS_ON;
133	writel(reg, mxsfb->base + LCDC_VDCTRL4);
134
135	writel(CTRL_RUN, mxsfb->base + LCDC_CTRL + REG_SET);
136}
137
138static void mxsfb_disable_controller(struct mxsfb_drm_private *mxsfb)
139{
140	u32 reg;
141
142	/*
143	 * Even if we disable the controller here, it will still continue
144	 * until its FIFOs are running out of data
145	 */
146	writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_CLR);
147
148	readl_poll_timeout(mxsfb->base + LCDC_CTRL, reg, !(reg & CTRL_RUN),
149			   0, 1000);
150
151	reg = readl(mxsfb->base + LCDC_VDCTRL4);
152	reg &= ~VDCTRL4_SYNC_SIGNALS_ON;
153	writel(reg, mxsfb->base + LCDC_VDCTRL4);
154
155	clk_disable_unprepare(mxsfb->clk);
156	if (mxsfb->clk_disp_axi)
157		clk_disable_unprepare(mxsfb->clk_disp_axi);
158}
159
160/*
161 * Clear the bit and poll it cleared.  This is usually called with
162 * a reset address and mask being either SFTRST(bit 31) or CLKGATE
163 * (bit 30).
164 */
165static int clear_poll_bit(void __iomem *addr, u32 mask)
166{
167	u32 reg;
168
169	writel(mask, addr + MXS_CLR_ADDR);
170	return readl_poll_timeout(addr, reg, !(reg & mask), 0, RESET_TIMEOUT);
171}
172
173static int mxsfb_reset_block(void __iomem *reset_addr)
174{
175	int ret;
176
177	ret = clear_poll_bit(reset_addr, MODULE_SFTRST);
178	if (ret)
179		return ret;
180
181	writel(MODULE_CLKGATE, reset_addr + MXS_CLR_ADDR);
182
183	ret = clear_poll_bit(reset_addr, MODULE_SFTRST);
184	if (ret)
185		return ret;
186
187	return clear_poll_bit(reset_addr, MODULE_CLKGATE);
188}
189
190static dma_addr_t mxsfb_get_fb_paddr(struct mxsfb_drm_private *mxsfb)
191{
192	struct drm_framebuffer *fb = mxsfb->pipe.plane.state->fb;
193	struct drm_gem_cma_object *gem;
194
195	if (!fb)
196		return 0;
197
198	gem = drm_fb_cma_get_gem_obj(fb, 0);
199	if (!gem)
200		return 0;
201
202	return gem->paddr;
203}
204
205static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
206{
207	struct drm_display_mode *m = &mxsfb->pipe.crtc.state->adjusted_mode;
208	const u32 bus_flags = mxsfb->connector.display_info.bus_flags;
209	u32 vdctrl0, vsync_pulse_len, hsync_pulse_len;
210	int err;
211
212	/*
213	 * It seems, you can't re-program the controller if it is still
214	 * running. This may lead to shifted pictures (FIFO issue?), so
215	 * first stop the controller and drain its FIFOs.
216	 */
217
218	/* Mandatory eLCDIF reset as per the Reference Manual */
219	err = mxsfb_reset_block(mxsfb->base);
220	if (err)
221		return;
222
223	/* Clear the FIFOs */
224	writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_SET);
225
226	err = mxsfb_set_pixel_fmt(mxsfb);
227	if (err)
228		return;
229
230	clk_set_rate(mxsfb->clk, m->crtc_clock * 1000);
231
232	writel(TRANSFER_COUNT_SET_VCOUNT(m->crtc_vdisplay) |
233	       TRANSFER_COUNT_SET_HCOUNT(m->crtc_hdisplay),
234	       mxsfb->base + mxsfb->devdata->transfer_count);
235
236	vsync_pulse_len = m->crtc_vsync_end - m->crtc_vsync_start;
237
238	vdctrl0 = VDCTRL0_ENABLE_PRESENT |	/* Always in DOTCLOCK mode */
239		  VDCTRL0_VSYNC_PERIOD_UNIT |
240		  VDCTRL0_VSYNC_PULSE_WIDTH_UNIT |
241		  VDCTRL0_SET_VSYNC_PULSE_WIDTH(vsync_pulse_len);
242	if (m->flags & DRM_MODE_FLAG_PHSYNC)
243		vdctrl0 |= VDCTRL0_HSYNC_ACT_HIGH;
244	if (m->flags & DRM_MODE_FLAG_PVSYNC)
245		vdctrl0 |= VDCTRL0_VSYNC_ACT_HIGH;
246	/* Make sure Data Enable is high active by default */
247	if (!(bus_flags & DRM_BUS_FLAG_DE_LOW))
248		vdctrl0 |= VDCTRL0_ENABLE_ACT_HIGH;
249	/*
250	 * DRM_BUS_FLAG_PIXDATA_DRIVE_ defines are controller centric,
251	 * controllers VDCTRL0_DOTCLK is display centric.
252	 * Drive on positive edge       -> display samples on falling edge
253	 * DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE -> VDCTRL0_DOTCLK_ACT_FALLING
254	 */
255	if (bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE)
256		vdctrl0 |= VDCTRL0_DOTCLK_ACT_FALLING;
257
258	writel(vdctrl0, mxsfb->base + LCDC_VDCTRL0);
259
260	mxsfb_set_bus_fmt(mxsfb);
261
262	/* Frame length in lines. */
263	writel(m->crtc_vtotal, mxsfb->base + LCDC_VDCTRL1);
264
265	/* Line length in units of clocks or pixels. */
266	hsync_pulse_len = m->crtc_hsync_end - m->crtc_hsync_start;
267	writel(set_hsync_pulse_width(mxsfb, hsync_pulse_len) |
268	       VDCTRL2_SET_HSYNC_PERIOD(m->crtc_htotal),
269	       mxsfb->base + LCDC_VDCTRL2);
270
271	writel(SET_HOR_WAIT_CNT(m->crtc_htotal - m->crtc_hsync_start) |
272	       SET_VERT_WAIT_CNT(m->crtc_vtotal - m->crtc_vsync_start),
273	       mxsfb->base + LCDC_VDCTRL3);
274
275	writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay),
276	       mxsfb->base + LCDC_VDCTRL4);
277}
278
279void mxsfb_crtc_enable(struct mxsfb_drm_private *mxsfb)
280{
281	dma_addr_t paddr;
282
283	mxsfb_enable_axi_clk(mxsfb);
284	mxsfb_crtc_mode_set_nofb(mxsfb);
285
286	/* Write cur_buf as well to avoid an initial corrupt frame */
287	paddr = mxsfb_get_fb_paddr(mxsfb);
288	if (paddr) {
289		writel(paddr, mxsfb->base + mxsfb->devdata->cur_buf);
290		writel(paddr, mxsfb->base + mxsfb->devdata->next_buf);
291	}
292
293	mxsfb_enable_controller(mxsfb);
294}
295
296void mxsfb_crtc_disable(struct mxsfb_drm_private *mxsfb)
297{
298	mxsfb_disable_controller(mxsfb);
299	mxsfb_disable_axi_clk(mxsfb);
300}
301
302void mxsfb_plane_atomic_update(struct mxsfb_drm_private *mxsfb,
303			       struct drm_plane_state *state)
304{
305	struct drm_simple_display_pipe *pipe = &mxsfb->pipe;
306	struct drm_crtc *crtc = &pipe->crtc;
307	struct drm_pending_vblank_event *event;
308	dma_addr_t paddr;
309
310	spin_lock_irq(&crtc->dev->event_lock);
311	event = crtc->state->event;
312	if (event) {
313		crtc->state->event = NULL;
314
315		if (drm_crtc_vblank_get(crtc) == 0) {
316			drm_crtc_arm_vblank_event(crtc, event);
317		} else {
318			drm_crtc_send_vblank_event(crtc, event);
319		}
320	}
321	spin_unlock_irq(&crtc->dev->event_lock);
322
323	paddr = mxsfb_get_fb_paddr(mxsfb);
324	if (paddr) {
325		mxsfb_enable_axi_clk(mxsfb);
326		writel(paddr, mxsfb->base + mxsfb->devdata->next_buf);
327		mxsfb_disable_axi_clk(mxsfb);
328	}
329}