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path: root/drivers/gpu/drm/tegra/rgb.c
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Diffstat (limited to 'drivers/gpu/drm/tegra/rgb.c')
-rw-r--r--drivers/gpu/drm/tegra/rgb.c354
1 files changed, 354 insertions, 0 deletions
diff --git a/drivers/gpu/drm/tegra/rgb.c b/drivers/gpu/drm/tegra/rgb.c
new file mode 100644
index 0000000000..79566c9ea8
--- /dev/null
+++ b/drivers/gpu/drm/tegra/rgb.c
@@ -0,0 +1,354 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012 Avionic Design GmbH
+ * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
+ */
+
+#include <linux/clk.h>
+#include <linux/of.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge_connector.h>
+#include <drm/drm_simple_kms_helper.h>
+
+#include "drm.h"
+#include "dc.h"
+
+struct tegra_rgb {
+ struct tegra_output output;
+ struct tegra_dc *dc;
+
+ struct clk *pll_d_out0;
+ struct clk *pll_d2_out0;
+ struct clk *clk_parent;
+ struct clk *clk;
+};
+
+static inline struct tegra_rgb *to_rgb(struct tegra_output *output)
+{
+ return container_of(output, struct tegra_rgb, output);
+}
+
+struct reg_entry {
+ unsigned long offset;
+ unsigned long value;
+};
+
+static const struct reg_entry rgb_enable[] = {
+ { DC_COM_PIN_OUTPUT_ENABLE(0), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_ENABLE(1), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_ENABLE(2), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_ENABLE(3), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_POLARITY(0), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_POLARITY(1), 0x01000000 },
+ { DC_COM_PIN_OUTPUT_POLARITY(2), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_POLARITY(3), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_DATA(0), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_DATA(1), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_DATA(2), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_DATA(3), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(0), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(1), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(2), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(3), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(4), 0x00210222 },
+ { DC_COM_PIN_OUTPUT_SELECT(5), 0x00002200 },
+ { DC_COM_PIN_OUTPUT_SELECT(6), 0x00020000 },
+};
+
+static const struct reg_entry rgb_disable[] = {
+ { DC_COM_PIN_OUTPUT_SELECT(6), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(5), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(4), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(3), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(2), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(1), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_SELECT(0), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_DATA(3), 0xaaaaaaaa },
+ { DC_COM_PIN_OUTPUT_DATA(2), 0xaaaaaaaa },
+ { DC_COM_PIN_OUTPUT_DATA(1), 0xaaaaaaaa },
+ { DC_COM_PIN_OUTPUT_DATA(0), 0xaaaaaaaa },
+ { DC_COM_PIN_OUTPUT_POLARITY(3), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_POLARITY(2), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_POLARITY(1), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_POLARITY(0), 0x00000000 },
+ { DC_COM_PIN_OUTPUT_ENABLE(3), 0x55555555 },
+ { DC_COM_PIN_OUTPUT_ENABLE(2), 0x55555555 },
+ { DC_COM_PIN_OUTPUT_ENABLE(1), 0x55150005 },
+ { DC_COM_PIN_OUTPUT_ENABLE(0), 0x55555555 },
+};
+
+static void tegra_dc_write_regs(struct tegra_dc *dc,
+ const struct reg_entry *table,
+ unsigned int num)
+{
+ unsigned int i;
+
+ for (i = 0; i < num; i++)
+ tegra_dc_writel(dc, table[i].value, table[i].offset);
+}
+
+static void tegra_rgb_encoder_disable(struct drm_encoder *encoder)
+{
+ struct tegra_output *output = encoder_to_output(encoder);
+ struct tegra_rgb *rgb = to_rgb(output);
+
+ tegra_dc_write_regs(rgb->dc, rgb_disable, ARRAY_SIZE(rgb_disable));
+ tegra_dc_commit(rgb->dc);
+}
+
+static void tegra_rgb_encoder_enable(struct drm_encoder *encoder)
+{
+ struct tegra_output *output = encoder_to_output(encoder);
+ struct tegra_rgb *rgb = to_rgb(output);
+ u32 value;
+
+ tegra_dc_write_regs(rgb->dc, rgb_enable, ARRAY_SIZE(rgb_enable));
+
+ value = DE_SELECT_ACTIVE | DE_CONTROL_NORMAL;
+ tegra_dc_writel(rgb->dc, value, DC_DISP_DATA_ENABLE_OPTIONS);
+
+ /* XXX: parameterize? */
+ value = tegra_dc_readl(rgb->dc, DC_COM_PIN_OUTPUT_POLARITY(1));
+ value &= ~LVS_OUTPUT_POLARITY_LOW;
+ value &= ~LHS_OUTPUT_POLARITY_LOW;
+ tegra_dc_writel(rgb->dc, value, DC_COM_PIN_OUTPUT_POLARITY(1));
+
+ /* XXX: parameterize? */
+ value = DISP_DATA_FORMAT_DF1P1C | DISP_ALIGNMENT_MSB |
+ DISP_ORDER_RED_BLUE;
+ tegra_dc_writel(rgb->dc, value, DC_DISP_DISP_INTERFACE_CONTROL);
+
+ tegra_dc_commit(rgb->dc);
+}
+
+static bool tegra_rgb_pll_rate_change_allowed(struct tegra_rgb *rgb)
+{
+ if (!rgb->pll_d2_out0)
+ return false;
+
+ if (!clk_is_match(rgb->clk_parent, rgb->pll_d_out0) &&
+ !clk_is_match(rgb->clk_parent, rgb->pll_d2_out0))
+ return false;
+
+ return true;
+}
+
+static int
+tegra_rgb_encoder_atomic_check(struct drm_encoder *encoder,
+ struct drm_crtc_state *crtc_state,
+ struct drm_connector_state *conn_state)
+{
+ struct tegra_output *output = encoder_to_output(encoder);
+ struct tegra_dc *dc = to_tegra_dc(conn_state->crtc);
+ unsigned long pclk = crtc_state->mode.clock * 1000;
+ struct tegra_rgb *rgb = to_rgb(output);
+ unsigned int div;
+ int err;
+
+ /*
+ * We may not want to change the frequency of the parent clock, since
+ * it may be a parent for other peripherals. This is due to the fact
+ * that on Tegra20 there's only a single clock dedicated to display
+ * (pll_d_out0), whereas later generations have a second one that can
+ * be used to independently drive a second output (pll_d2_out0).
+ *
+ * As a way to support multiple outputs on Tegra20 as well, pll_p is
+ * typically used as the parent clock for the display controllers.
+ * But this comes at a cost: pll_p is the parent of several other
+ * peripherals, so its frequency shouldn't change out of the blue.
+ *
+ * The best we can do at this point is to use the shift clock divider
+ * and hope that the desired frequency can be matched (or at least
+ * matched sufficiently close that the panel will still work).
+ */
+ if (tegra_rgb_pll_rate_change_allowed(rgb)) {
+ /*
+ * Set display controller clock to x2 of PCLK in order to
+ * produce higher resolution pulse positions.
+ */
+ div = 2;
+ pclk *= 2;
+ } else {
+ div = ((clk_get_rate(rgb->clk) * 2) / pclk) - 2;
+ pclk = 0;
+ }
+
+ err = tegra_dc_state_setup_clock(dc, crtc_state, rgb->clk_parent,
+ pclk, div);
+ if (err < 0) {
+ dev_err(output->dev, "failed to setup CRTC state: %d\n", err);
+ return err;
+ }
+
+ return err;
+}
+
+static const struct drm_encoder_helper_funcs tegra_rgb_encoder_helper_funcs = {
+ .disable = tegra_rgb_encoder_disable,
+ .enable = tegra_rgb_encoder_enable,
+ .atomic_check = tegra_rgb_encoder_atomic_check,
+};
+
+int tegra_dc_rgb_probe(struct tegra_dc *dc)
+{
+ struct device_node *np;
+ struct tegra_rgb *rgb;
+ int err;
+
+ np = of_get_child_by_name(dc->dev->of_node, "rgb");
+ if (!np || !of_device_is_available(np))
+ return -ENODEV;
+
+ rgb = devm_kzalloc(dc->dev, sizeof(*rgb), GFP_KERNEL);
+ if (!rgb)
+ return -ENOMEM;
+
+ rgb->output.dev = dc->dev;
+ rgb->output.of_node = np;
+ rgb->dc = dc;
+
+ err = tegra_output_probe(&rgb->output);
+ if (err < 0)
+ return err;
+
+ rgb->clk = devm_clk_get(dc->dev, NULL);
+ if (IS_ERR(rgb->clk)) {
+ dev_err(dc->dev, "failed to get clock\n");
+ return PTR_ERR(rgb->clk);
+ }
+
+ rgb->clk_parent = devm_clk_get(dc->dev, "parent");
+ if (IS_ERR(rgb->clk_parent)) {
+ dev_err(dc->dev, "failed to get parent clock\n");
+ return PTR_ERR(rgb->clk_parent);
+ }
+
+ err = clk_set_parent(rgb->clk, rgb->clk_parent);
+ if (err < 0) {
+ dev_err(dc->dev, "failed to set parent clock: %d\n", err);
+ return err;
+ }
+
+ rgb->pll_d_out0 = clk_get_sys(NULL, "pll_d_out0");
+ if (IS_ERR(rgb->pll_d_out0)) {
+ err = PTR_ERR(rgb->pll_d_out0);
+ dev_err(dc->dev, "failed to get pll_d_out0: %d\n", err);
+ return err;
+ }
+
+ if (dc->soc->has_pll_d2_out0) {
+ rgb->pll_d2_out0 = clk_get_sys(NULL, "pll_d2_out0");
+ if (IS_ERR(rgb->pll_d2_out0)) {
+ err = PTR_ERR(rgb->pll_d2_out0);
+ dev_err(dc->dev, "failed to get pll_d2_out0: %d\n", err);
+ return err;
+ }
+ }
+
+ dc->rgb = &rgb->output;
+
+ return 0;
+}
+
+void tegra_dc_rgb_remove(struct tegra_dc *dc)
+{
+ struct tegra_rgb *rgb;
+
+ if (!dc->rgb)
+ return;
+
+ rgb = to_rgb(dc->rgb);
+ clk_put(rgb->pll_d2_out0);
+ clk_put(rgb->pll_d_out0);
+
+ tegra_output_remove(dc->rgb);
+ dc->rgb = NULL;
+}
+
+int tegra_dc_rgb_init(struct drm_device *drm, struct tegra_dc *dc)
+{
+ struct tegra_output *output = dc->rgb;
+ struct drm_connector *connector;
+ int err;
+
+ if (!dc->rgb)
+ return -ENODEV;
+
+ drm_simple_encoder_init(drm, &output->encoder, DRM_MODE_ENCODER_LVDS);
+ drm_encoder_helper_add(&output->encoder,
+ &tegra_rgb_encoder_helper_funcs);
+
+ /*
+ * Wrap directly-connected panel into DRM bridge in order to let
+ * DRM core to handle panel for us.
+ */
+ if (output->panel) {
+ output->bridge = devm_drm_panel_bridge_add(output->dev,
+ output->panel);
+ if (IS_ERR(output->bridge)) {
+ dev_err(output->dev,
+ "failed to wrap panel into bridge: %pe\n",
+ output->bridge);
+ return PTR_ERR(output->bridge);
+ }
+
+ output->panel = NULL;
+ }
+
+ /*
+ * Tegra devices that have LVDS panel utilize LVDS encoder bridge
+ * for converting up to 28 LCD LVTTL lanes into 5/4 LVDS lanes that
+ * go to display panel's receiver.
+ *
+ * Encoder usually have a power-down control which needs to be enabled
+ * in order to transmit data to the panel. Historically devices that
+ * use an older device-tree version didn't model the bridge, assuming
+ * that encoder is turned ON by default, while today's DRM allows us
+ * to model LVDS encoder properly.
+ *
+ * Newer device-trees utilize LVDS encoder bridge, which provides
+ * us with a connector and handles the display panel.
+ *
+ * For older device-trees we wrapped panel into the panel-bridge.
+ */
+ if (output->bridge) {
+ err = drm_bridge_attach(&output->encoder, output->bridge,
+ NULL, DRM_BRIDGE_ATTACH_NO_CONNECTOR);
+ if (err)
+ return err;
+
+ connector = drm_bridge_connector_init(drm, &output->encoder);
+ if (IS_ERR(connector)) {
+ dev_err(output->dev,
+ "failed to initialize bridge connector: %pe\n",
+ connector);
+ return PTR_ERR(connector);
+ }
+
+ drm_connector_attach_encoder(connector, &output->encoder);
+ }
+
+ err = tegra_output_init(drm, output);
+ if (err < 0) {
+ dev_err(output->dev, "failed to initialize output: %d\n", err);
+ return err;
+ }
+
+ /*
+ * Other outputs can be attached to either display controller. The RGB
+ * outputs are an exception and work only with their parent display
+ * controller.
+ */
+ output->encoder.possible_crtcs = drm_crtc_mask(&dc->base);
+
+ return 0;
+}
+
+int tegra_dc_rgb_exit(struct tegra_dc *dc)
+{
+ if (dc->rgb)
+ tegra_output_exit(dc->rgb);
+
+ return 0;
+}