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