1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (C) 2016 Marek Vasut <marex@denx.de>
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.
12 #include <drm/drm_atomic_helper.h>
13 #include <drm/drm_crtc.h>
14 #include <drm/drm_fb_helper.h>
15 #include <drm/drm_fb_cma_helper.h>
16 #include <drm/drm_gem_cma_helper.h>
17 #include <drm/drm_of.h>
18 #include <drm/drm_plane_helper.h>
19 #include <drm/drm_probe_helper.h>
20 #include <drm/drm_simple_kms_helper.h>
21 #include <linux/clk.h>
22 #include <linux/iopoll.h>
23 #include <linux/of_graph.h>
24 #include <linux/platform_data/simplefb.h>
25 #include <video/videomode.h>
27 #include "mxsfb_drv.h"
28 #include "mxsfb_regs.h"
30 #define MXS_SET_ADDR 0x4
31 #define MXS_CLR_ADDR 0x8
32 #define MODULE_CLKGATE BIT(30)
33 #define MODULE_SFTRST BIT(31)
34 /* 1 second delay should be plenty of time for block reset */
35 #define RESET_TIMEOUT 1000000
37 static u32 set_hsync_pulse_width(struct mxsfb_drm_private *mxsfb, u32 val)
39 return (val & mxsfb->devdata->hs_wdth_mask) <<
40 mxsfb->devdata->hs_wdth_shift;
43 /* Setup the MXSFB registers for decoding the pixels out of the framebuffer */
44 static int mxsfb_set_pixel_fmt(struct mxsfb_drm_private *mxsfb)
46 struct drm_crtc *crtc = &mxsfb->pipe.crtc;
47 struct drm_device *drm = crtc->dev;
48 const u32 format = crtc->primary->state->fb->format->format;
51 ctrl = CTRL_BYPASS_COUNT | CTRL_MASTER;
54 * WARNING: The bus width, CTRL_SET_BUS_WIDTH(), is configured to
55 * match the selected mode here. This differs from the original
56 * MXSFB driver, which had the option to configure the bus width
57 * to arbitrary value. This limitation should not pose an issue.
60 /* CTRL1 contains IRQ config and status bits, preserve those. */
61 ctrl1 = readl(mxsfb->base + LCDC_CTRL1);
62 ctrl1 &= CTRL1_CUR_FRAME_DONE_IRQ_EN | CTRL1_CUR_FRAME_DONE_IRQ;
65 case DRM_FORMAT_RGB565:
66 dev_dbg(drm->dev, "Setting up RGB565 mode\n");
67 ctrl |= CTRL_SET_WORD_LENGTH(0);
68 ctrl1 |= CTRL1_SET_BYTE_PACKAGING(0xf);
70 case DRM_FORMAT_XRGB8888:
71 dev_dbg(drm->dev, "Setting up XRGB8888 mode\n");
72 ctrl |= CTRL_SET_WORD_LENGTH(3);
73 /* Do not use packed pixels = one pixel per word instead. */
74 ctrl1 |= CTRL1_SET_BYTE_PACKAGING(0x7);
77 dev_err(drm->dev, "Unhandled pixel format %08x\n", format);
81 writel(ctrl1, mxsfb->base + LCDC_CTRL1);
82 writel(ctrl, mxsfb->base + LCDC_CTRL);
87 static void mxsfb_set_bus_fmt(struct mxsfb_drm_private *mxsfb)
89 struct drm_crtc *crtc = &mxsfb->pipe.crtc;
90 struct drm_device *drm = crtc->dev;
91 u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
94 reg = readl(mxsfb->base + LCDC_CTRL);
96 if (mxsfb->connector.display_info.num_bus_formats)
97 bus_format = mxsfb->connector.display_info.bus_formats[0];
99 reg &= ~CTRL_BUS_WIDTH_MASK;
100 switch (bus_format) {
101 case MEDIA_BUS_FMT_RGB565_1X16:
102 reg |= CTRL_SET_BUS_WIDTH(STMLCDIF_16BIT);
104 case MEDIA_BUS_FMT_RGB666_1X18:
105 reg |= CTRL_SET_BUS_WIDTH(STMLCDIF_18BIT);
107 case MEDIA_BUS_FMT_RGB888_1X24:
108 reg |= CTRL_SET_BUS_WIDTH(STMLCDIF_24BIT);
111 dev_err(drm->dev, "Unknown media bus format %d\n", bus_format);
114 writel(reg, mxsfb->base + LCDC_CTRL);
117 static void mxsfb_enable_controller(struct mxsfb_drm_private *mxsfb)
121 if (mxsfb->clk_disp_axi)
122 clk_prepare_enable(mxsfb->clk_disp_axi);
123 clk_prepare_enable(mxsfb->clk);
125 /* If it was disabled, re-enable the mode again */
126 writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_SET);
128 /* Enable the SYNC signals first, then the DMA engine */
129 reg = readl(mxsfb->base + LCDC_VDCTRL4);
130 reg |= VDCTRL4_SYNC_SIGNALS_ON;
131 writel(reg, mxsfb->base + LCDC_VDCTRL4);
133 writel(CTRL_RUN, mxsfb->base + LCDC_CTRL + REG_SET);
136 static void mxsfb_disable_controller(struct mxsfb_drm_private *mxsfb)
141 * Even if we disable the controller here, it will still continue
142 * until its FIFOs are running out of data
144 writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_CLR);
146 readl_poll_timeout(mxsfb->base + LCDC_CTRL, reg, !(reg & CTRL_RUN),
149 reg = readl(mxsfb->base + LCDC_VDCTRL4);
150 reg &= ~VDCTRL4_SYNC_SIGNALS_ON;
151 writel(reg, mxsfb->base + LCDC_VDCTRL4);
153 clk_disable_unprepare(mxsfb->clk);
154 if (mxsfb->clk_disp_axi)
155 clk_disable_unprepare(mxsfb->clk_disp_axi);
159 * Clear the bit and poll it cleared. This is usually called with
160 * a reset address and mask being either SFTRST(bit 31) or CLKGATE
163 static int clear_poll_bit(void __iomem *addr, u32 mask)
167 writel(mask, addr + MXS_CLR_ADDR);
168 return readl_poll_timeout(addr, reg, !(reg & mask), 0, RESET_TIMEOUT);
171 static int mxsfb_reset_block(void __iomem *reset_addr)
175 ret = clear_poll_bit(reset_addr, MODULE_SFTRST);
179 writel(MODULE_CLKGATE, reset_addr + MXS_CLR_ADDR);
181 ret = clear_poll_bit(reset_addr, MODULE_SFTRST);
185 return clear_poll_bit(reset_addr, MODULE_CLKGATE);
188 static dma_addr_t mxsfb_get_fb_paddr(struct mxsfb_drm_private *mxsfb)
190 struct drm_framebuffer *fb = mxsfb->pipe.plane.state->fb;
191 struct drm_gem_cma_object *gem;
196 gem = drm_fb_cma_get_gem_obj(fb, 0);
203 static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
205 struct drm_display_mode *m = &mxsfb->pipe.crtc.state->adjusted_mode;
206 const u32 bus_flags = mxsfb->connector.display_info.bus_flags;
207 u32 vdctrl0, vsync_pulse_len, hsync_pulse_len;
211 * It seems, you can't re-program the controller if it is still
212 * running. This may lead to shifted pictures (FIFO issue?), so
213 * first stop the controller and drain its FIFOs.
216 /* Mandatory eLCDIF reset as per the Reference Manual */
217 err = mxsfb_reset_block(mxsfb->base);
221 /* Clear the FIFOs */
222 writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_SET);
224 err = mxsfb_set_pixel_fmt(mxsfb);
228 clk_set_rate(mxsfb->clk, m->crtc_clock * 1000);
230 writel(TRANSFER_COUNT_SET_VCOUNT(m->crtc_vdisplay) |
231 TRANSFER_COUNT_SET_HCOUNT(m->crtc_hdisplay),
232 mxsfb->base + mxsfb->devdata->transfer_count);
234 vsync_pulse_len = m->crtc_vsync_end - m->crtc_vsync_start;
236 vdctrl0 = VDCTRL0_ENABLE_PRESENT | /* Always in DOTCLOCK mode */
237 VDCTRL0_VSYNC_PERIOD_UNIT |
238 VDCTRL0_VSYNC_PULSE_WIDTH_UNIT |
239 VDCTRL0_SET_VSYNC_PULSE_WIDTH(vsync_pulse_len);
240 if (m->flags & DRM_MODE_FLAG_PHSYNC)
241 vdctrl0 |= VDCTRL0_HSYNC_ACT_HIGH;
242 if (m->flags & DRM_MODE_FLAG_PVSYNC)
243 vdctrl0 |= VDCTRL0_VSYNC_ACT_HIGH;
244 /* Make sure Data Enable is high active by default */
245 if (!(bus_flags & DRM_BUS_FLAG_DE_LOW))
246 vdctrl0 |= VDCTRL0_ENABLE_ACT_HIGH;
248 * DRM_BUS_FLAG_PIXDATA_DRIVE_ defines are controller centric,
249 * controllers VDCTRL0_DOTCLK is display centric.
250 * Drive on positive edge -> display samples on falling edge
251 * DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE -> VDCTRL0_DOTCLK_ACT_FALLING
253 if (bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE)
254 vdctrl0 |= VDCTRL0_DOTCLK_ACT_FALLING;
256 writel(vdctrl0, mxsfb->base + LCDC_VDCTRL0);
258 mxsfb_set_bus_fmt(mxsfb);
260 /* Frame length in lines. */
261 writel(m->crtc_vtotal, mxsfb->base + LCDC_VDCTRL1);
263 /* Line length in units of clocks or pixels. */
264 hsync_pulse_len = m->crtc_hsync_end - m->crtc_hsync_start;
265 writel(set_hsync_pulse_width(mxsfb, hsync_pulse_len) |
266 VDCTRL2_SET_HSYNC_PERIOD(m->crtc_htotal),
267 mxsfb->base + LCDC_VDCTRL2);
269 writel(SET_HOR_WAIT_CNT(m->crtc_htotal - m->crtc_hsync_start) |
270 SET_VERT_WAIT_CNT(m->crtc_vtotal - m->crtc_vsync_start),
271 mxsfb->base + LCDC_VDCTRL3);
273 writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay),
274 mxsfb->base + LCDC_VDCTRL4);
277 void mxsfb_crtc_enable(struct mxsfb_drm_private *mxsfb)
281 mxsfb_enable_axi_clk(mxsfb);
282 mxsfb_crtc_mode_set_nofb(mxsfb);
284 /* Write cur_buf as well to avoid an initial corrupt frame */
285 paddr = mxsfb_get_fb_paddr(mxsfb);
287 writel(paddr, mxsfb->base + mxsfb->devdata->cur_buf);
288 writel(paddr, mxsfb->base + mxsfb->devdata->next_buf);
291 mxsfb_enable_controller(mxsfb);
294 void mxsfb_crtc_disable(struct mxsfb_drm_private *mxsfb)
296 mxsfb_disable_controller(mxsfb);
297 mxsfb_disable_axi_clk(mxsfb);
300 void mxsfb_plane_atomic_update(struct mxsfb_drm_private *mxsfb,
301 struct drm_plane_state *state)
303 struct drm_simple_display_pipe *pipe = &mxsfb->pipe;
304 struct drm_crtc *crtc = &pipe->crtc;
305 struct drm_pending_vblank_event *event;
308 spin_lock_irq(&crtc->dev->event_lock);
309 event = crtc->state->event;
311 crtc->state->event = NULL;
313 if (drm_crtc_vblank_get(crtc) == 0) {
314 drm_crtc_arm_vblank_event(crtc, event);
316 drm_crtc_send_vblank_event(crtc, event);
319 spin_unlock_irq(&crtc->dev->event_lock);
321 paddr = mxsfb_get_fb_paddr(mxsfb);
323 mxsfb_enable_axi_clk(mxsfb);
324 writel(paddr, mxsfb->base + mxsfb->devdata->next_buf);
325 mxsfb_disable_axi_clk(mxsfb);