linux/drivers/gpu/drm/tegra/rgb.c

318 lines
9.0 KiB
C

// 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 <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 *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);
/* XXX: parameterize? */
value = SC0_H_QUALIFIER_NONE | SC1_H_QUALIFIER_NONE;
tegra_dc_writel(rgb->dc, value, DC_DISP_SHIFT_CLOCK_OPTIONS);
tegra_dc_commit(rgb->dc);
}
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).
*/
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;
}
dc->rgb = &rgb->output;
return 0;
}
int tegra_dc_rgb_remove(struct tegra_dc *dc)
{
if (!dc->rgb)
return 0;
tegra_output_remove(dc->rgb);
dc->rgb = NULL;
return 0;
}
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) {
dev_err(output->dev, "failed to attach bridge: %d\n",
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;
}