diff options
Diffstat (limited to 'drivers/gpu/drm/tegra/rgb.c')
-rw-r--r-- | drivers/gpu/drm/tegra/rgb.c | 354 |
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; +} |