drm/msm/dsi: support CPHY mode for 7nm pll/phy

Add the required changes to support 7nm pll/phy in CPHY mode.

This adds a "qcom,dsi-phy-cphy-mode" property for the PHY node to enable
the CPHY mode.
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20210617144349.28448-4-jonathan@marek.caSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/dsi/dsi_host.c

@@ -27,6 +27,7 @@
 #include "dsi_cfg.h"
 #include "msm_kms.h"
 #include "msm_gem.h"
+#include "phy/dsi_phy.h"
 
 #define DSI_RESET_TOGGLE_DELAY_MS 20
 
@@ -167,6 +168,9 @@ struct msm_dsi_host {
 	int dlane_swap;
 	int num_data_lanes;
 
+	/* from phy DT */
+	bool cphy_mode;
+
 	u32 dma_cmd_ctrl_restore;
 
 	bool registered;
@@ -510,6 +514,7 @@ int msm_dsi_runtime_resume(struct device *dev)
 
 int dsi_link_clk_set_rate_6g(struct msm_dsi_host *msm_host)
 {
+	u32 byte_intf_rate;
 	int ret;
 
 	DBG("Set clk rates: pclk=%d, byteclk=%d",
@@ -529,8 +534,13 @@ int dsi_link_clk_set_rate_6g(struct msm_dsi_host *msm_host)
 	}
 
 	if (msm_host->byte_intf_clk) {
-		ret = clk_set_rate(msm_host->byte_intf_clk,
-				   msm_host->byte_clk_rate / 2);
+		/* For CPHY, byte_intf_clk is same as byte_clk */
+		if (msm_host->cphy_mode)
+			byte_intf_rate = msm_host->byte_clk_rate;
+		else
+			byte_intf_rate = msm_host->byte_clk_rate / 2;
+
+		ret = clk_set_rate(msm_host->byte_intf_clk, byte_intf_rate);
 		if (ret) {
 			pr_err("%s: Failed to set rate byte intf clk, %d\n",
 			       __func__, ret);
@@ -710,6 +720,10 @@ static void dsi_calc_pclk(struct msm_dsi_host *msm_host, bool is_dual_dsi)
 		lanes = 1;
 	}
 
+	/* CPHY "byte_clk" is in units of 16 bits */
+	if (msm_host->cphy_mode)
+		do_div(pclk_bpp, (16 * lanes));
+	else
 		do_div(pclk_bpp, (8 * lanes));
 
 	msm_host->pixel_clk_rate = pclk_rate;
@@ -936,6 +950,9 @@ static void dsi_ctrl_config(struct msm_dsi_host *msm_host, bool enable,
 	data |= DSI_CTRL_ENABLE;
 
 	dsi_write(msm_host, REG_DSI_CTRL, data);
+
+	if (msm_host->cphy_mode)
+		dsi_write(msm_host, REG_DSI_CPHY_MODE_CTRL, BIT(0));
 }
 
 static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_dual_dsi)
@@ -2226,6 +2243,8 @@ int msm_dsi_host_set_src_pll(struct mipi_dsi_host *host,
 	struct clk *byte_clk_provider, *pixel_clk_provider;
 	int ret;
 
+	msm_host->cphy_mode = src_phy->cphy_mode;
+
 	ret = msm_dsi_phy_get_clk_provider(src_phy,
 				&byte_clk_provider, &pixel_clk_provider);
 	if (ret) {
@@ -2297,6 +2316,13 @@ void msm_dsi_host_get_phy_clk_req(struct mipi_dsi_host *host,
 		return;
 	}
 
+	/* CPHY transmits 16 bits over 7 clock cycles
+	 * "byte_clk" is in units of 16-bits (see dsi_calc_pclk),
+	 * so multiply by 7 to get the "bitclk rate"
+	 */
+	if (msm_host->cphy_mode)
+		clk_req->bitclk_rate = msm_host->byte_clk_rate * 7;
+	else
 		clk_req->bitclk_rate = msm_host->byte_clk_rate * 8;
 	clk_req->escclk_rate = msm_host->esc_clk_rate;
 }

drivers/gpu/drm/msm/dsi/phy/dsi_phy.c

@@ -5,6 +5,7 @@
 
 #include <linux/clk-provider.h>
 #include <linux/platform_device.h>
+#include <dt-bindings/phy/phy.h>
 
 #include "dsi_phy.h"
 
@@ -461,6 +462,51 @@ int msm_dsi_dphy_timing_calc_v4(struct msm_dsi_dphy_timing *timing,
 	return 0;
 }
 
+int msm_dsi_cphy_timing_calc_v4(struct msm_dsi_dphy_timing *timing,
+	struct msm_dsi_phy_clk_request *clk_req)
+{
+	const unsigned long bit_rate = clk_req->bitclk_rate;
+	const unsigned long esc_rate = clk_req->escclk_rate;
+	s32 ui, ui_x7;
+	s32 tmax, tmin;
+	s32 coeff = 1000; /* Precision, should avoid overflow */
+	s32 temp;
+
+	if (!bit_rate || !esc_rate)
+		return -EINVAL;
+
+	ui = mult_frac(NSEC_PER_MSEC, coeff, bit_rate / 1000);
+	ui_x7 = ui * 7;
+
+	temp = S_DIV_ROUND_UP(38 * coeff, ui_x7);
+	tmin = max_t(s32, temp, 0);
+	temp = (95 * coeff) / ui_x7;
+	tmax = max_t(s32, temp, 0);
+	timing->clk_prepare = linear_inter(tmax, tmin, 50, 0, false);
+
+	tmin = DIV_ROUND_UP(50 * coeff, ui_x7);
+	tmax = 255;
+	timing->hs_rqst = linear_inter(tmax, tmin, 1, 0, false);
+
+	tmin = DIV_ROUND_UP(100 * coeff, ui_x7) - 1;
+	tmax = 255;
+	timing->hs_exit = linear_inter(tmax, tmin, 10, 0, false);
+
+	tmin = 1;
+	tmax = 32;
+	timing->shared_timings.clk_post = linear_inter(tmax, tmin, 80, 0, false);
+
+	tmin = min_t(s32, 64, S_DIV_ROUND_UP(262 * coeff, ui_x7) - 1);
+	tmax = 64;
+	timing->shared_timings.clk_pre = linear_inter(tmax, tmin, 20, 0, false);
+
+	DBG("%d, %d, %d, %d, %d",
+		timing->shared_timings.clk_pre, timing->shared_timings.clk_post,
+		timing->clk_prepare, timing->hs_exit, timing->hs_rqst);
+
+	return 0;
+}
+
 static int dsi_phy_regulator_init(struct msm_dsi_phy *phy)
 {
 	struct regulator_bulk_data *s = phy->supplies;
@@ -626,6 +672,7 @@ static int dsi_phy_driver_probe(struct platform_device *pdev)
 	struct msm_dsi_phy *phy;
 	struct device *dev = &pdev->dev;
 	const struct of_device_id *match;
+	u32 phy_type;
 	int ret;
 
 	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
@@ -657,6 +704,8 @@ static int dsi_phy_driver_probe(struct platform_device *pdev)
 
 	phy->regulator_ldo_mode = of_property_read_bool(dev->of_node,
 				"qcom,dsi-phy-regulator-ldo-mode");
+	if (!of_property_read_u32(dev->of_node, "phy-type", &phy_type))
+		phy->cphy_mode = (phy_type == PHY_TYPE_CPHY);
 
 	phy->base = msm_ioremap_size(pdev, "dsi_phy", "DSI_PHY", &phy->base_size);
 	if (IS_ERR(phy->base)) {

drivers/gpu/drm/msm/dsi/phy/dsi_phy.h

@@ -99,6 +99,7 @@ struct msm_dsi_phy {
 
 	enum msm_dsi_phy_usecase usecase;
 	bool regulator_ldo_mode;
+	bool cphy_mode;
 
 	struct clk_hw *vco_hw;
 	bool pll_on;
@@ -119,5 +120,7 @@ int msm_dsi_dphy_timing_calc_v3(struct msm_dsi_dphy_timing *timing,
 				struct msm_dsi_phy_clk_request *clk_req);
 int msm_dsi_dphy_timing_calc_v4(struct msm_dsi_dphy_timing *timing,
 				struct msm_dsi_phy_clk_request *clk_req);
+int msm_dsi_cphy_timing_calc_v4(struct msm_dsi_dphy_timing *timing,
+				struct msm_dsi_phy_clk_request *clk_req);
 
 #endif /* __DSI_PHY_H__ */

drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c

@@ -256,7 +256,7 @@ static void dsi_pll_commit(struct dsi_pll_7nm *pll, struct dsi_pll_config *confi
 		  (config->frac_div_start & 0x30000) >> 16);
 	dsi_phy_write(base + REG_DSI_7nm_PHY_PLL_PLL_LOCKDET_RATE_1, 0x40);
 	dsi_phy_write(base + REG_DSI_7nm_PHY_PLL_PLL_LOCK_DELAY, 0x06);
-	dsi_phy_write(base + REG_DSI_7nm_PHY_PLL_CMODE_1, 0x10); /* TODO: 0x00 for CPHY */
+	dsi_phy_write(base + REG_DSI_7nm_PHY_PLL_CMODE_1, pll->phy->cphy_mode ? 0x00 : 0x10);
 	dsi_phy_write(base + REG_DSI_7nm_PHY_PLL_CLOCK_INVERTERS, config->pll_clock_inverters);
 }
 
@@ -642,7 +642,8 @@ static int pll_7nm_register(struct dsi_pll_7nm *pll_7nm, struct clk_hw **provide
 
 	/* DSI Byte clock = VCO_CLK / OUT_DIV / BIT_DIV / 8 */
 	hw = devm_clk_hw_register_fixed_factor(dev, clk_name, parent,
-					  CLK_SET_RATE_PARENT, 1, 8);
+					  CLK_SET_RATE_PARENT, 1,
+					  pll_7nm->phy->cphy_mode ? 7 : 8);
 	if (IS_ERR(hw)) {
 		ret = PTR_ERR(hw);
 		goto fail;
@@ -663,13 +664,26 @@ static int pll_7nm_register(struct dsi_pll_7nm *pll_7nm, struct clk_hw **provide
 	snprintf(clk_name, 32, "dsi%d_pll_post_out_div_clk", pll_7nm->phy->id);
 	snprintf(parent, 32, "dsi%d_pll_out_div_clk", pll_7nm->phy->id);
 
-	hw = devm_clk_hw_register_fixed_factor(dev, clk_name, parent,
-					  0, 1, 4);
+	if (pll_7nm->phy->cphy_mode)
+		hw = devm_clk_hw_register_fixed_factor(dev, clk_name, parent, 0, 2, 7);
+	else
+		hw = devm_clk_hw_register_fixed_factor(dev, clk_name, parent, 0, 1, 4);
 	if (IS_ERR(hw)) {
 		ret = PTR_ERR(hw);
 		goto fail;
 	}
 
+	/* in CPHY mode, pclk_mux will always have post_out_div as parent
+	 * don't register a pclk_mux clock and just use post_out_div instead
+	 */
+	if (pll_7nm->phy->cphy_mode) {
+		u32 data;
+
+		data = dsi_phy_read(pll_7nm->phy->base + REG_DSI_7nm_PHY_CMN_CLK_CFG1);
+		dsi_phy_write(pll_7nm->phy->base + REG_DSI_7nm_PHY_CMN_CLK_CFG1, data | 3);
+
+		snprintf(parent, 32, "dsi%d_pll_post_out_div_clk", pll_7nm->phy->id);
+	} else {
 		snprintf(clk_name, 32, "dsi%d_pclk_mux", pll_7nm->phy->id);
 		snprintf(parent, 32, "dsi%d_pll_bit_clk", pll_7nm->phy->id);
 		snprintf(parent2, 32, "dsi%d_pll_by_2_bit_clk", pll_7nm->phy->id);
@@ -687,8 +701,10 @@ static int pll_7nm_register(struct dsi_pll_7nm *pll_7nm, struct clk_hw **provide
 			goto fail;
 		}
 
-	snprintf(clk_name, 32, "dsi%d_phy_pll_out_dsiclk", pll_7nm->phy->id);
 		snprintf(parent, 32, "dsi%d_pclk_mux", pll_7nm->phy->id);
+	}
+
+	snprintf(clk_name, 32, "dsi%d_phy_pll_out_dsiclk", pll_7nm->phy->id);
 
 	/* PIX CLK DIV : DIV_CTRL_7_4*/
 	hw = devm_clk_hw_register_divider(dev, clk_name, parent,
@@ -813,15 +829,21 @@ static int dsi_7nm_phy_enable(struct msm_dsi_phy *phy,
 	struct msm_dsi_dphy_timing *timing = &phy->timing;
 	void __iomem *base = phy->base;
 	bool less_than_1500_mhz;
-	u32 vreg_ctrl_0, glbl_str_swi_cal_sel_ctrl, glbl_hstx_str_ctrl_0;
+	u32 vreg_ctrl_0, vreg_ctrl_1, lane_ctrl0;
+	u32 glbl_pemph_ctrl_0;
+	u32 glbl_str_swi_cal_sel_ctrl, glbl_hstx_str_ctrl_0;
 	u32 glbl_rescode_top_ctrl, glbl_rescode_bot_ctrl;
 	u32 data;
 
 	DBG("");
 
-	if (msm_dsi_dphy_timing_calc_v4(timing, clk_req)) {
+	if (phy->cphy_mode)
+		ret = msm_dsi_cphy_timing_calc_v4(timing, clk_req);
+	else
+		ret = msm_dsi_dphy_timing_calc_v4(timing, clk_req);
+	if (ret) {
 		DRM_DEV_ERROR(&phy->pdev->dev,
-			"%s: D-PHY timing calculation failed\n", __func__);
+			"%s: PHY timing calculation failed\n", __func__);
 		return -EINVAL;
 	}
 
@@ -842,6 +864,10 @@ static int dsi_7nm_phy_enable(struct msm_dsi_phy *phy,
 	/* Alter PHY configurations if data rate less than 1.5GHZ*/
 	less_than_1500_mhz = (clk_req->bitclk_rate <= 1500000000);
 
+	/* For C-PHY, no low power settings for lower clk rate */
+	if (phy->cphy_mode)
+		less_than_1500_mhz = false;
+
 	if (phy->cfg->quirks & DSI_PHY_7NM_QUIRK_V4_1) {
 		vreg_ctrl_0 = less_than_1500_mhz ? 0x53 : 0x52;
 		glbl_rescode_top_ctrl = less_than_1500_mhz ? 0x3d :  0x00;
@@ -856,6 +882,17 @@ static int dsi_7nm_phy_enable(struct msm_dsi_phy *phy,
 		glbl_rescode_bot_ctrl = 0x3c;
 	}
 
+	if (phy->cphy_mode) {
+		vreg_ctrl_0 = 0x51;
+		vreg_ctrl_1 = 0x55;
+		glbl_pemph_ctrl_0 = 0x11;
+		lane_ctrl0 = 0x17;
+	} else {
+		vreg_ctrl_1 = 0x5c;
+		glbl_pemph_ctrl_0 = 0x00;
+		lane_ctrl0 = 0x1f;
+	}
+
 	/* de-assert digital and pll power down */
 	data = BIT(6) | BIT(5);
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_CTRL_0, data);
@@ -876,15 +913,22 @@ static int dsi_7nm_phy_enable(struct msm_dsi_phy *phy,
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_LANE_CFG0, 0x21);
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_LANE_CFG1, 0x84);
 
+	if (phy->cphy_mode)
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_GLBL_CTRL, BIT(6));
+
 	/* Enable LDO */
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_VREG_CTRL_0, vreg_ctrl_0);
-	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_VREG_CTRL_1, 0x5c);
+	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_VREG_CTRL_1, vreg_ctrl_1);
+
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_CTRL_3, 0x00);
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_GLBL_STR_SWI_CAL_SEL_CTRL,
 		      glbl_str_swi_cal_sel_ctrl);
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_GLBL_HSTX_STR_CTRL_0,
 		      glbl_hstx_str_ctrl_0);
-	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_GLBL_PEMPH_CTRL_0, 0x00);
+	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_GLBL_PEMPH_CTRL_0,
+		      glbl_pemph_ctrl_0);
+	if (phy->cphy_mode)
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_GLBL_PEMPH_CTRL_1, 0x01);
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_GLBL_RESCODE_OFFSET_TOP_CTRL,
 		      glbl_rescode_top_ctrl);
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_GLBL_RESCODE_OFFSET_BOT_CTRL,
@@ -894,9 +938,10 @@ static int dsi_7nm_phy_enable(struct msm_dsi_phy *phy,
 	/* Remove power down from all blocks */
 	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_CTRL_0, 0x7f);
 
-	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_LANE_CTRL0, 0x1f);
+	dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_LANE_CTRL0, lane_ctrl0);
 
 	/* Select full-rate mode */
+	if (!phy->cphy_mode)
 		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_CTRL_2, 0x40);
 
 	ret = dsi_7nm_set_usecase(phy);
@@ -907,6 +952,19 @@ static int dsi_7nm_phy_enable(struct msm_dsi_phy *phy,
 	}
 
 	/* DSI PHY timings */
+	if (phy->cphy_mode) {
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_0, 0x00);
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_4, timing->hs_exit);
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_5,
+			timing->shared_timings.clk_pre);
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_6, timing->clk_prepare);
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_7,
+			timing->shared_timings.clk_post);
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_8, timing->hs_rqst);
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_9, 0x02);
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_10, 0x04);
+		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_11, 0x00);
+	} else {
 		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_0, 0x00);
 		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_1, timing->clk_zero);
 		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_2, timing->clk_prepare);
@@ -923,6 +981,7 @@ static int dsi_7nm_phy_enable(struct msm_dsi_phy *phy,
 			timing->shared_timings.clk_pre);
 		dsi_phy_write(base + REG_DSI_7nm_PHY_CMN_TIMING_CTRL_13,
 			timing->shared_timings.clk_post);
+	}
 
 	/* DSI lane settings */
 	dsi_phy_hw_v4_0_lane_settings(phy);