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path: root/drivers/gpu/drm/pl111/pl111_display.c
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Diffstat (limited to 'drivers/gpu/drm/pl111/pl111_display.c')
-rw-r--r--drivers/gpu/drm/pl111/pl111_display.c596
1 files changed, 596 insertions, 0 deletions
diff --git a/drivers/gpu/drm/pl111/pl111_display.c b/drivers/gpu/drm/pl111/pl111_display.c
new file mode 100644
index 000000000..6afdf260a
--- /dev/null
+++ b/drivers/gpu/drm/pl111/pl111_display.c
@@ -0,0 +1,596 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * (C) COPYRIGHT 2012-2013 ARM Limited. All rights reserved.
+ *
+ * Parts of this file were based on sources as follows:
+ *
+ * Copyright (c) 2006-2008 Intel Corporation
+ * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
+ * Copyright (C) 2011 Texas Instruments
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dma-buf.h>
+#include <linux/media-bus-format.h>
+#include <linux/of_graph.h>
+
+#include <drm/drm_fb_dma_helper.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_gem_atomic_helper.h>
+#include <drm/drm_gem_dma_helper.h>
+#include <drm/drm_vblank.h>
+
+#include "pl111_drm.h"
+
+irqreturn_t pl111_irq(int irq, void *data)
+{
+ struct pl111_drm_dev_private *priv = data;
+ u32 irq_stat;
+ irqreturn_t status = IRQ_NONE;
+
+ irq_stat = readl(priv->regs + CLCD_PL111_MIS);
+
+ if (!irq_stat)
+ return IRQ_NONE;
+
+ if (irq_stat & CLCD_IRQ_NEXTBASE_UPDATE) {
+ drm_crtc_handle_vblank(&priv->pipe.crtc);
+
+ status = IRQ_HANDLED;
+ }
+
+ /* Clear the interrupt once done */
+ writel(irq_stat, priv->regs + CLCD_PL111_ICR);
+
+ return status;
+}
+
+static enum drm_mode_status
+pl111_mode_valid(struct drm_simple_display_pipe *pipe,
+ const struct drm_display_mode *mode)
+{
+ struct drm_device *drm = pipe->crtc.dev;
+ struct pl111_drm_dev_private *priv = drm->dev_private;
+ u32 cpp = priv->variant->fb_bpp / 8;
+ u64 bw;
+
+ /*
+ * We use the pixelclock to also account for interlaced modes, the
+ * resulting bandwidth is in bytes per second.
+ */
+ bw = mode->clock * 1000ULL; /* In Hz */
+ bw = bw * mode->hdisplay * mode->vdisplay * cpp;
+ bw = div_u64(bw, mode->htotal * mode->vtotal);
+
+ /*
+ * If no bandwidth constraints, anything goes, else
+ * check if we are too fast.
+ */
+ if (priv->memory_bw && (bw > priv->memory_bw)) {
+ DRM_DEBUG_KMS("%d x %d @ %d Hz, %d cpp, bw %llu too fast\n",
+ mode->hdisplay, mode->vdisplay,
+ mode->clock * 1000, cpp, bw);
+
+ return MODE_BAD;
+ }
+ DRM_DEBUG_KMS("%d x %d @ %d Hz, %d cpp, bw %llu bytes/s OK\n",
+ mode->hdisplay, mode->vdisplay,
+ mode->clock * 1000, cpp, bw);
+
+ return MODE_OK;
+}
+
+static int pl111_display_check(struct drm_simple_display_pipe *pipe,
+ struct drm_plane_state *pstate,
+ struct drm_crtc_state *cstate)
+{
+ const struct drm_display_mode *mode = &cstate->mode;
+ struct drm_framebuffer *old_fb = pipe->plane.state->fb;
+ struct drm_framebuffer *fb = pstate->fb;
+
+ if (mode->hdisplay % 16)
+ return -EINVAL;
+
+ if (fb) {
+ u32 offset = drm_fb_dma_get_gem_addr(fb, pstate, 0);
+
+ /* FB base address must be dword aligned. */
+ if (offset & 3)
+ return -EINVAL;
+
+ /* There's no pitch register -- the mode's hdisplay
+ * controls it.
+ */
+ if (fb->pitches[0] != mode->hdisplay * fb->format->cpp[0])
+ return -EINVAL;
+
+ /* We can't change the FB format in a flicker-free
+ * manner (and only update it during CRTC enable).
+ */
+ if (old_fb && old_fb->format != fb->format)
+ cstate->mode_changed = true;
+ }
+
+ return 0;
+}
+
+static void pl111_display_enable(struct drm_simple_display_pipe *pipe,
+ struct drm_crtc_state *cstate,
+ struct drm_plane_state *plane_state)
+{
+ struct drm_crtc *crtc = &pipe->crtc;
+ struct drm_plane *plane = &pipe->plane;
+ struct drm_device *drm = crtc->dev;
+ struct pl111_drm_dev_private *priv = drm->dev_private;
+ const struct drm_display_mode *mode = &cstate->mode;
+ struct drm_framebuffer *fb = plane->state->fb;
+ struct drm_connector *connector = priv->connector;
+ struct drm_bridge *bridge = priv->bridge;
+ bool grayscale = false;
+ u32 cntl;
+ u32 ppl, hsw, hfp, hbp;
+ u32 lpp, vsw, vfp, vbp;
+ u32 cpl, tim2;
+ int ret;
+
+ ret = clk_set_rate(priv->clk, mode->clock * 1000);
+ if (ret) {
+ dev_err(drm->dev,
+ "Failed to set pixel clock rate to %d: %d\n",
+ mode->clock * 1000, ret);
+ }
+
+ clk_prepare_enable(priv->clk);
+
+ ppl = (mode->hdisplay / 16) - 1;
+ hsw = mode->hsync_end - mode->hsync_start - 1;
+ hfp = mode->hsync_start - mode->hdisplay - 1;
+ hbp = mode->htotal - mode->hsync_end - 1;
+
+ lpp = mode->vdisplay - 1;
+ vsw = mode->vsync_end - mode->vsync_start - 1;
+ vfp = mode->vsync_start - mode->vdisplay;
+ vbp = mode->vtotal - mode->vsync_end;
+
+ cpl = mode->hdisplay - 1;
+
+ writel((ppl << 2) |
+ (hsw << 8) |
+ (hfp << 16) |
+ (hbp << 24),
+ priv->regs + CLCD_TIM0);
+ writel(lpp |
+ (vsw << 10) |
+ (vfp << 16) |
+ (vbp << 24),
+ priv->regs + CLCD_TIM1);
+
+ spin_lock(&priv->tim2_lock);
+
+ tim2 = readl(priv->regs + CLCD_TIM2);
+ tim2 &= (TIM2_BCD | TIM2_PCD_LO_MASK | TIM2_PCD_HI_MASK);
+
+ if (priv->variant->broken_clockdivider)
+ tim2 |= TIM2_BCD;
+
+ if (mode->flags & DRM_MODE_FLAG_NHSYNC)
+ tim2 |= TIM2_IHS;
+
+ if (mode->flags & DRM_MODE_FLAG_NVSYNC)
+ tim2 |= TIM2_IVS;
+
+ if (connector) {
+ if (connector->display_info.bus_flags & DRM_BUS_FLAG_DE_LOW)
+ tim2 |= TIM2_IOE;
+
+ if (connector->display_info.bus_flags &
+ DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)
+ tim2 |= TIM2_IPC;
+
+ if (connector->display_info.num_bus_formats == 1 &&
+ connector->display_info.bus_formats[0] ==
+ MEDIA_BUS_FMT_Y8_1X8)
+ grayscale = true;
+
+ /*
+ * The AC pin bias frequency is set to max count when using
+ * grayscale so at least once in a while we will reverse
+ * polarity and get rid of any DC built up that could
+ * damage the display.
+ */
+ if (grayscale)
+ tim2 |= TIM2_ACB_MASK;
+ }
+
+ if (bridge) {
+ const struct drm_bridge_timings *btimings = bridge->timings;
+
+ /*
+ * Here is when things get really fun. Sometimes the bridge
+ * timings are such that the signal out from PL11x is not
+ * stable before the receiving bridge (such as a dumb VGA DAC
+ * or similar) samples it. If that happens, we compensate by
+ * the only method we have: output the data on the opposite
+ * edge of the clock so it is for sure stable when it gets
+ * sampled.
+ *
+ * The PL111 manual does not contain proper timining diagrams
+ * or data for these details, but we know from experiments
+ * that the setup time is more than 3000 picoseconds (3 ns).
+ * If we have a bridge that requires the signal to be stable
+ * earlier than 3000 ps before the clock pulse, we have to
+ * output the data on the opposite edge to avoid flicker.
+ */
+ if (btimings && btimings->setup_time_ps >= 3000)
+ tim2 ^= TIM2_IPC;
+ }
+
+ tim2 |= cpl << 16;
+ writel(tim2, priv->regs + CLCD_TIM2);
+ spin_unlock(&priv->tim2_lock);
+
+ writel(0, priv->regs + CLCD_TIM3);
+
+ /*
+ * Detect grayscale bus format. We do not support a grayscale mode
+ * toward userspace, instead we expose an RGB24 buffer and then the
+ * hardware will activate its grayscaler to convert to the grayscale
+ * format.
+ */
+ if (grayscale)
+ cntl = CNTL_LCDEN | CNTL_LCDMONO8;
+ else
+ /* Else we assume TFT display */
+ cntl = CNTL_LCDEN | CNTL_LCDTFT | CNTL_LCDVCOMP(1);
+
+ /* On the ST Micro variant, assume all 24 bits are connected */
+ if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_ST_CDWID_24;
+
+ /*
+ * Note that the ARM hardware's format reader takes 'r' from
+ * the low bit, while DRM formats list channels from high bit
+ * to low bit as you read left to right. The ST Micro version of
+ * the PL110 (LCDC) however uses the standard DRM format.
+ */
+ switch (fb->format->format) {
+ case DRM_FORMAT_BGR888:
+ /* Only supported on the ST Micro variant */
+ if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_ST_LCDBPP24_PACKED | CNTL_BGR;
+ break;
+ case DRM_FORMAT_RGB888:
+ /* Only supported on the ST Micro variant */
+ if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_ST_LCDBPP24_PACKED;
+ break;
+ case DRM_FORMAT_ABGR8888:
+ case DRM_FORMAT_XBGR8888:
+ if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_LCDBPP24 | CNTL_BGR;
+ else
+ cntl |= CNTL_LCDBPP24;
+ break;
+ case DRM_FORMAT_ARGB8888:
+ case DRM_FORMAT_XRGB8888:
+ if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_LCDBPP24;
+ else
+ cntl |= CNTL_LCDBPP24 | CNTL_BGR;
+ break;
+ case DRM_FORMAT_BGR565:
+ if (priv->variant->is_pl110)
+ cntl |= CNTL_LCDBPP16;
+ else if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_LCDBPP16 | CNTL_ST_1XBPP_565 | CNTL_BGR;
+ else
+ cntl |= CNTL_LCDBPP16_565;
+ break;
+ case DRM_FORMAT_RGB565:
+ if (priv->variant->is_pl110)
+ cntl |= CNTL_LCDBPP16 | CNTL_BGR;
+ else if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_LCDBPP16 | CNTL_ST_1XBPP_565;
+ else
+ cntl |= CNTL_LCDBPP16_565 | CNTL_BGR;
+ break;
+ case DRM_FORMAT_ABGR1555:
+ case DRM_FORMAT_XBGR1555:
+ cntl |= CNTL_LCDBPP16;
+ if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_ST_1XBPP_5551 | CNTL_BGR;
+ break;
+ case DRM_FORMAT_ARGB1555:
+ case DRM_FORMAT_XRGB1555:
+ cntl |= CNTL_LCDBPP16;
+ if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_ST_1XBPP_5551;
+ else
+ cntl |= CNTL_BGR;
+ break;
+ case DRM_FORMAT_ABGR4444:
+ case DRM_FORMAT_XBGR4444:
+ cntl |= CNTL_LCDBPP16_444;
+ if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_ST_1XBPP_444 | CNTL_BGR;
+ break;
+ case DRM_FORMAT_ARGB4444:
+ case DRM_FORMAT_XRGB4444:
+ cntl |= CNTL_LCDBPP16_444;
+ if (priv->variant->st_bitmux_control)
+ cntl |= CNTL_ST_1XBPP_444;
+ else
+ cntl |= CNTL_BGR;
+ break;
+ default:
+ WARN_ONCE(true, "Unknown FB format 0x%08x\n",
+ fb->format->format);
+ break;
+ }
+
+ /* The PL110 in Integrator/Versatile does the BGR routing externally */
+ if (priv->variant->external_bgr)
+ cntl &= ~CNTL_BGR;
+
+ /* Power sequence: first enable and chill */
+ writel(cntl, priv->regs + priv->ctrl);
+
+ /*
+ * We expect this delay to stabilize the contrast
+ * voltage Vee as stipulated by the manual
+ */
+ msleep(20);
+
+ if (priv->variant_display_enable)
+ priv->variant_display_enable(drm, fb->format->format);
+
+ /* Power Up */
+ cntl |= CNTL_LCDPWR;
+ writel(cntl, priv->regs + priv->ctrl);
+
+ if (!priv->variant->broken_vblank)
+ drm_crtc_vblank_on(crtc);
+}
+
+static void pl111_display_disable(struct drm_simple_display_pipe *pipe)
+{
+ struct drm_crtc *crtc = &pipe->crtc;
+ struct drm_device *drm = crtc->dev;
+ struct pl111_drm_dev_private *priv = drm->dev_private;
+ u32 cntl;
+
+ if (!priv->variant->broken_vblank)
+ drm_crtc_vblank_off(crtc);
+
+ /* Power Down */
+ cntl = readl(priv->regs + priv->ctrl);
+ if (cntl & CNTL_LCDPWR) {
+ cntl &= ~CNTL_LCDPWR;
+ writel(cntl, priv->regs + priv->ctrl);
+ }
+
+ /*
+ * We expect this delay to stabilize the contrast voltage Vee as
+ * stipulated by the manual
+ */
+ msleep(20);
+
+ if (priv->variant_display_disable)
+ priv->variant_display_disable(drm);
+
+ /* Disable */
+ writel(0, priv->regs + priv->ctrl);
+
+ clk_disable_unprepare(priv->clk);
+}
+
+static void pl111_display_update(struct drm_simple_display_pipe *pipe,
+ struct drm_plane_state *old_pstate)
+{
+ struct drm_crtc *crtc = &pipe->crtc;
+ struct drm_device *drm = crtc->dev;
+ struct pl111_drm_dev_private *priv = drm->dev_private;
+ struct drm_pending_vblank_event *event = crtc->state->event;
+ struct drm_plane *plane = &pipe->plane;
+ struct drm_plane_state *pstate = plane->state;
+ struct drm_framebuffer *fb = pstate->fb;
+
+ if (fb) {
+ u32 addr = drm_fb_dma_get_gem_addr(fb, pstate, 0);
+
+ writel(addr, priv->regs + CLCD_UBAS);
+ }
+
+ if (event) {
+ crtc->state->event = NULL;
+
+ spin_lock_irq(&crtc->dev->event_lock);
+ if (crtc->state->active && drm_crtc_vblank_get(crtc) == 0)
+ drm_crtc_arm_vblank_event(crtc, event);
+ else
+ drm_crtc_send_vblank_event(crtc, event);
+ spin_unlock_irq(&crtc->dev->event_lock);
+ }
+}
+
+static int pl111_display_enable_vblank(struct drm_simple_display_pipe *pipe)
+{
+ struct drm_crtc *crtc = &pipe->crtc;
+ struct drm_device *drm = crtc->dev;
+ struct pl111_drm_dev_private *priv = drm->dev_private;
+
+ writel(CLCD_IRQ_NEXTBASE_UPDATE, priv->regs + priv->ienb);
+
+ return 0;
+}
+
+static void pl111_display_disable_vblank(struct drm_simple_display_pipe *pipe)
+{
+ struct drm_crtc *crtc = &pipe->crtc;
+ struct drm_device *drm = crtc->dev;
+ struct pl111_drm_dev_private *priv = drm->dev_private;
+
+ writel(0, priv->regs + priv->ienb);
+}
+
+static struct drm_simple_display_pipe_funcs pl111_display_funcs = {
+ .mode_valid = pl111_mode_valid,
+ .check = pl111_display_check,
+ .enable = pl111_display_enable,
+ .disable = pl111_display_disable,
+ .update = pl111_display_update,
+};
+
+static int pl111_clk_div_choose_div(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate, bool set_parent)
+{
+ int best_div = 1, div;
+ struct clk_hw *parent = clk_hw_get_parent(hw);
+ unsigned long best_prate = 0;
+ unsigned long best_diff = ~0ul;
+ int max_div = (1 << (TIM2_PCD_LO_BITS + TIM2_PCD_HI_BITS)) - 1;
+
+ for (div = 1; div < max_div; div++) {
+ unsigned long this_prate, div_rate, diff;
+
+ if (set_parent)
+ this_prate = clk_hw_round_rate(parent, rate * div);
+ else
+ this_prate = *prate;
+ div_rate = DIV_ROUND_UP_ULL(this_prate, div);
+ diff = abs(rate - div_rate);
+
+ if (diff < best_diff) {
+ best_div = div;
+ best_diff = diff;
+ best_prate = this_prate;
+ }
+ }
+
+ *prate = best_prate;
+ return best_div;
+}
+
+static long pl111_clk_div_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ int div = pl111_clk_div_choose_div(hw, rate, prate, true);
+
+ return DIV_ROUND_UP_ULL(*prate, div);
+}
+
+static unsigned long pl111_clk_div_recalc_rate(struct clk_hw *hw,
+ unsigned long prate)
+{
+ struct pl111_drm_dev_private *priv =
+ container_of(hw, struct pl111_drm_dev_private, clk_div);
+ u32 tim2 = readl(priv->regs + CLCD_TIM2);
+ int div;
+
+ if (tim2 & TIM2_BCD)
+ return prate;
+
+ div = tim2 & TIM2_PCD_LO_MASK;
+ div |= (tim2 & TIM2_PCD_HI_MASK) >>
+ (TIM2_PCD_HI_SHIFT - TIM2_PCD_LO_BITS);
+ div += 2;
+
+ return DIV_ROUND_UP_ULL(prate, div);
+}
+
+static int pl111_clk_div_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long prate)
+{
+ struct pl111_drm_dev_private *priv =
+ container_of(hw, struct pl111_drm_dev_private, clk_div);
+ int div = pl111_clk_div_choose_div(hw, rate, &prate, false);
+ u32 tim2;
+
+ spin_lock(&priv->tim2_lock);
+ tim2 = readl(priv->regs + CLCD_TIM2);
+ tim2 &= ~(TIM2_BCD | TIM2_PCD_LO_MASK | TIM2_PCD_HI_MASK);
+
+ if (div == 1) {
+ tim2 |= TIM2_BCD;
+ } else {
+ div -= 2;
+ tim2 |= div & TIM2_PCD_LO_MASK;
+ tim2 |= (div >> TIM2_PCD_LO_BITS) << TIM2_PCD_HI_SHIFT;
+ }
+
+ writel(tim2, priv->regs + CLCD_TIM2);
+ spin_unlock(&priv->tim2_lock);
+
+ return 0;
+}
+
+static const struct clk_ops pl111_clk_div_ops = {
+ .recalc_rate = pl111_clk_div_recalc_rate,
+ .round_rate = pl111_clk_div_round_rate,
+ .set_rate = pl111_clk_div_set_rate,
+};
+
+static int
+pl111_init_clock_divider(struct drm_device *drm)
+{
+ struct pl111_drm_dev_private *priv = drm->dev_private;
+ struct clk *parent = devm_clk_get(drm->dev, "clcdclk");
+ struct clk_hw *div = &priv->clk_div;
+ const char *parent_name;
+ struct clk_init_data init = {
+ .name = "pl111_div",
+ .ops = &pl111_clk_div_ops,
+ .parent_names = &parent_name,
+ .num_parents = 1,
+ .flags = CLK_SET_RATE_PARENT,
+ };
+ int ret;
+
+ if (IS_ERR(parent)) {
+ dev_err(drm->dev, "CLCD: unable to get clcdclk.\n");
+ return PTR_ERR(parent);
+ }
+
+ spin_lock_init(&priv->tim2_lock);
+
+ /* If the clock divider is broken, use the parent directly */
+ if (priv->variant->broken_clockdivider) {
+ priv->clk = parent;
+ return 0;
+ }
+ parent_name = __clk_get_name(parent);
+ div->init = &init;
+
+ ret = devm_clk_hw_register(drm->dev, div);
+
+ priv->clk = div->clk;
+ return ret;
+}
+
+int pl111_display_init(struct drm_device *drm)
+{
+ struct pl111_drm_dev_private *priv = drm->dev_private;
+ int ret;
+
+ ret = pl111_init_clock_divider(drm);
+ if (ret)
+ return ret;
+
+ if (!priv->variant->broken_vblank) {
+ pl111_display_funcs.enable_vblank = pl111_display_enable_vblank;
+ pl111_display_funcs.disable_vblank = pl111_display_disable_vblank;
+ }
+
+ ret = drm_simple_display_pipe_init(drm, &priv->pipe,
+ &pl111_display_funcs,
+ priv->variant->formats,
+ priv->variant->nformats,
+ NULL,
+ priv->connector);
+ if (ret)
+ return ret;
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 17:49:14 +0000