[PATCH v3 3/4] drm/stm: dsi: expose DSI PHY internal clock
Raphael Gallais-Pou
raphael.gallais-pou at foss.st.com
Thu Jan 4 05:44:33 PST 2024
DSISRC __________
__\_
| \
pll4_p_ck ->| 1 |____dsi_k
ck_dsi_phy ->| 0 |
|____/
A DSI clock is missing in the clock framework. Looking at the
clk_summary, it appears that 'ck_dsi_phy' is not implemented. Since the
DSI kernel clock is based on the internal DSI pll. The common clock
driver can not directly expose this 'ck_dsi_phy' clock because it does
not contain any common registers with the DSI. Thus it needs to be done
directly within the DSI phy driver.
Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou at foss.st.com>
---
Changes in v3:
- Fix smatch warning:
.../dw_mipi_dsi-stm.c:719 dw_mipi_dsi_stm_probe() warn: 'dsi->pclk'
from clk_prepare_enable() not released on lines: 719.
---
drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 247 ++++++++++++++++++++++----
1 file changed, 216 insertions(+), 31 deletions(-)
diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
index 82fff9e84345..b20123854c4a 100644
--- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
+++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
@@ -7,7 +7,9 @@
*/
#include <linux/clk.h>
+#include <linux/clk-provider.h>
#include <linux/iopoll.h>
+#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
@@ -77,9 +79,12 @@ enum dsi_color {
struct dw_mipi_dsi_stm {
void __iomem *base;
+ struct device *dev;
struct clk *pllref_clk;
struct clk *pclk;
+ struct clk_hw txbyte_clk;
struct dw_mipi_dsi *dsi;
+ struct dw_mipi_dsi_plat_data pdata;
u32 hw_version;
int lane_min_kbps;
int lane_max_kbps;
@@ -196,29 +201,198 @@ static int dsi_pll_get_params(struct dw_mipi_dsi_stm *dsi,
return 0;
}
-static int dw_mipi_dsi_phy_init(void *priv_data)
+#define clk_to_dw_mipi_dsi_stm(clk) \
+ container_of(clk, struct dw_mipi_dsi_stm, txbyte_clk)
+
+static void dw_mipi_dsi_clk_disable(struct clk_hw *clk)
{
- struct dw_mipi_dsi_stm *dsi = priv_data;
+ struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(clk);
+
+ DRM_DEBUG_DRIVER("\n");
+
+ /* Disable the DSI PLL */
+ dsi_clear(dsi, DSI_WRPCR, WRPCR_PLLEN);
+
+ /* Disable the regulator */
+ dsi_clear(dsi, DSI_WRPCR, WRPCR_REGEN | WRPCR_BGREN);
+}
+
+static int dw_mipi_dsi_clk_enable(struct clk_hw *clk)
+{
+ struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(clk);
u32 val;
int ret;
+ DRM_DEBUG_DRIVER("\n");
+
/* Enable the regulator */
dsi_set(dsi, DSI_WRPCR, WRPCR_REGEN | WRPCR_BGREN);
- ret = readl_poll_timeout(dsi->base + DSI_WISR, val, val & WISR_RRS,
- SLEEP_US, TIMEOUT_US);
+ ret = readl_poll_timeout_atomic(dsi->base + DSI_WISR, val, val & WISR_RRS,
+ SLEEP_US, TIMEOUT_US);
if (ret)
DRM_DEBUG_DRIVER("!TIMEOUT! waiting REGU, let's continue\n");
/* Enable the DSI PLL & wait for its lock */
dsi_set(dsi, DSI_WRPCR, WRPCR_PLLEN);
- ret = readl_poll_timeout(dsi->base + DSI_WISR, val, val & WISR_PLLLS,
- SLEEP_US, TIMEOUT_US);
+ ret = readl_poll_timeout_atomic(dsi->base + DSI_WISR, val, val & WISR_PLLLS,
+ SLEEP_US, TIMEOUT_US);
if (ret)
DRM_DEBUG_DRIVER("!TIMEOUT! waiting PLL, let's continue\n");
return 0;
}
+static int dw_mipi_dsi_clk_is_enabled(struct clk_hw *hw)
+{
+ struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
+
+ return dsi_read(dsi, DSI_WRPCR) & WRPCR_PLLEN;
+}
+
+static unsigned long dw_mipi_dsi_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
+ unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+ u32 val;
+
+ DRM_DEBUG_DRIVER("\n");
+
+ pll_in_khz = (unsigned int)(parent_rate / 1000);
+
+ val = dsi_read(dsi, DSI_WRPCR);
+
+ idf = (val & WRPCR_IDF) >> 11;
+ if (!idf)
+ idf = 1;
+ ndiv = (val & WRPCR_NDIV) >> 2;
+ odf = int_pow(2, (val & WRPCR_ODF) >> 16);
+
+ /* Get the adjusted pll out value */
+ pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
+
+ return (unsigned long)pll_out_khz * 1000;
+}
+
+static long dw_mipi_dsi_clk_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
+ unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+ int ret;
+
+ DRM_DEBUG_DRIVER("\n");
+
+ pll_in_khz = (unsigned int)(*parent_rate / 1000);
+
+ /* Compute best pll parameters */
+ idf = 0;
+ ndiv = 0;
+ odf = 0;
+
+ ret = dsi_pll_get_params(dsi, pll_in_khz, rate / 1000,
+ &idf, &ndiv, &odf);
+ if (ret)
+ DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
+
+ /* Get the adjusted pll out value */
+ pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
+
+ return pll_out_khz * 1000;
+}
+
+static int dw_mipi_dsi_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
+ unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+ int ret;
+ u32 val;
+
+ DRM_DEBUG_DRIVER("\n");
+
+ pll_in_khz = (unsigned int)(parent_rate / 1000);
+
+ /* Compute best pll parameters */
+ idf = 0;
+ ndiv = 0;
+ odf = 0;
+
+ ret = dsi_pll_get_params(dsi, pll_in_khz, rate / 1000, &idf, &ndiv, &odf);
+ if (ret)
+ DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
+
+ /* Get the adjusted pll out value */
+ pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
+
+ /* Set the PLL division factors */
+ dsi_update_bits(dsi, DSI_WRPCR, WRPCR_NDIV | WRPCR_IDF | WRPCR_ODF,
+ (ndiv << 2) | (idf << 11) | ((ffs(odf) - 1) << 16));
+
+ /* Compute uix4 & set the bit period in high-speed mode */
+ val = 4000000 / pll_out_khz;
+ dsi_update_bits(dsi, DSI_WPCR0, WPCR0_UIX4, val);
+
+ return 0;
+}
+
+static void dw_mipi_dsi_clk_unregister(void *data)
+{
+ struct dw_mipi_dsi_stm *dsi = data;
+
+ DRM_DEBUG_DRIVER("\n");
+
+ of_clk_del_provider(dsi->dev->of_node);
+ clk_hw_unregister(&dsi->txbyte_clk);
+}
+
+static const struct clk_ops dw_mipi_dsi_stm_clk_ops = {
+ .enable = dw_mipi_dsi_clk_enable,
+ .disable = dw_mipi_dsi_clk_disable,
+ .is_enabled = dw_mipi_dsi_clk_is_enabled,
+ .recalc_rate = dw_mipi_dsi_clk_recalc_rate,
+ .round_rate = dw_mipi_dsi_clk_round_rate,
+ .set_rate = dw_mipi_dsi_clk_set_rate,
+};
+
+static struct clk_init_data cdata_init = {
+ .name = "ck_dsi_phy",
+ .ops = &dw_mipi_dsi_stm_clk_ops,
+ .parent_names = (const char * []) {"ck_hse"},
+ .num_parents = 1,
+};
+
+static int dw_mipi_dsi_clk_register(struct dw_mipi_dsi_stm *dsi,
+ struct device *dev)
+{
+ struct device_node *node = dev->of_node;
+ int ret;
+
+ DRM_DEBUG_DRIVER("Registering clk\n");
+
+ dsi->txbyte_clk.init = &cdata_init;
+
+ ret = clk_hw_register(dev, &dsi->txbyte_clk);
+ if (ret)
+ return ret;
+
+ ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get,
+ &dsi->txbyte_clk);
+ if (ret)
+ clk_hw_unregister(&dsi->txbyte_clk);
+
+ return ret;
+}
+
+static int dw_mipi_dsi_phy_init(void *priv_data)
+{
+ struct dw_mipi_dsi_stm *dsi = priv_data;
+ int ret;
+
+ ret = clk_prepare_enable(dsi->txbyte_clk.clk);
+ return ret;
+}
+
static void dw_mipi_dsi_phy_power_on(void *priv_data)
{
struct dw_mipi_dsi_stm *dsi = priv_data;
@@ -235,6 +409,8 @@ static void dw_mipi_dsi_phy_power_off(void *priv_data)
DRM_DEBUG_DRIVER("\n");
+ clk_disable_unprepare(dsi->txbyte_clk.clk);
+
/* Disable the DSI wrapper */
dsi_clear(dsi, DSI_WCR, WCR_DSIEN);
}
@@ -245,9 +421,8 @@ dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
unsigned int *lane_mbps)
{
struct dw_mipi_dsi_stm *dsi = priv_data;
- unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+ unsigned int pll_in_khz, pll_out_khz;
int ret, bpp;
- u32 val;
pll_in_khz = (unsigned int)(clk_get_rate(dsi->pllref_clk) / 1000);
@@ -268,25 +443,10 @@ dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
DRM_WARN("Warning min phy mbps is used\n");
}
- /* Compute best pll parameters */
- idf = 0;
- ndiv = 0;
- odf = 0;
- ret = dsi_pll_get_params(dsi, pll_in_khz, pll_out_khz,
- &idf, &ndiv, &odf);
+ ret = clk_set_rate((dsi->txbyte_clk.clk), pll_out_khz * 1000);
if (ret)
- DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
-
- /* Get the adjusted pll out value */
- pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
-
- /* Set the PLL division factors */
- dsi_update_bits(dsi, DSI_WRPCR, WRPCR_NDIV | WRPCR_IDF | WRPCR_ODF,
- (ndiv << 2) | (idf << 11) | ((ffs(odf) - 1) << 16));
-
- /* Compute uix4 & set the bit period in high-speed mode */
- val = 4000000 / pll_out_khz;
- dsi_update_bits(dsi, DSI_WPCR0, WPCR0_UIX4, val);
+ DRM_DEBUG_DRIVER("ERROR Could not set rate of %d to %s clk->name",
+ pll_out_khz, clk_hw_get_name(&dsi->txbyte_clk));
/* Select video mode by resetting DSIM bit */
dsi_clear(dsi, DSI_WCFGR, WCFGR_DSIM);
@@ -445,6 +605,7 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct dw_mipi_dsi_stm *dsi;
+ const struct dw_mipi_dsi_plat_data *pdata = of_device_get_match_data(dev);
int ret;
dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
@@ -514,18 +675,41 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
dsi->lane_max_kbps *= 2;
}
- dw_mipi_dsi_stm_plat_data.base = dsi->base;
- dw_mipi_dsi_stm_plat_data.priv_data = dsi;
+ dsi->pdata = *pdata;
+ dsi->pdata.base = dsi->base;
+ dsi->pdata.priv_data = dsi;
+
+ dsi->pdata.max_data_lanes = 2;
+ dsi->pdata.phy_ops = &dw_mipi_dsi_stm_phy_ops;
platform_set_drvdata(pdev, dsi);
- dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
+ dsi->dsi = dw_mipi_dsi_probe(pdev, &dsi->pdata);
if (IS_ERR(dsi->dsi)) {
ret = PTR_ERR(dsi->dsi);
dev_err_probe(dev, ret, "Failed to initialize mipi dsi host\n");
goto err_dsi_probe;
}
+ /*
+ * We need to wait for the generic bridge to probe before enabling and
+ * register the internal pixel clock.
+ */
+ ret = clk_prepare_enable(dsi->pclk);
+ if (ret) {
+ DRM_ERROR("%s: Failed to enable peripheral clk\n", __func__);
+ goto err_dsi_probe;
+ }
+
+ ret = dw_mipi_dsi_clk_register(dsi, dev);
+ if (ret) {
+ DRM_ERROR("Failed to register DSI pixel clock: %d\n", ret);
+ clk_disable_unprepare(dsi->pclk);
+ goto err_dsi_probe;
+ }
+
+ clk_disable_unprepare(dsi->pclk);
+
return 0;
err_dsi_probe:
@@ -542,12 +726,13 @@ static void dw_mipi_dsi_stm_remove(struct platform_device *pdev)
dw_mipi_dsi_remove(dsi->dsi);
clk_disable_unprepare(dsi->pllref_clk);
+ dw_mipi_dsi_clk_unregister(dsi);
regulator_disable(dsi->vdd_supply);
}
static int dw_mipi_dsi_stm_suspend(struct device *dev)
{
- struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
+ struct dw_mipi_dsi_stm *dsi = dev_get_drvdata(dev);
DRM_DEBUG_DRIVER("\n");
@@ -560,7 +745,7 @@ static int dw_mipi_dsi_stm_suspend(struct device *dev)
static int dw_mipi_dsi_stm_resume(struct device *dev)
{
- struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
+ struct dw_mipi_dsi_stm *dsi = dev_get_drvdata(dev);
int ret;
DRM_DEBUG_DRIVER("\n");
--
2.25.1
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