[PATCH 0/4] MIPI DSI Controller support for SAM9X75 series

[PATCH 0/4] MIPI DSI Controller support for SAM9X75 series

[Manikandan Muralidharan]

This patch series adds support for the Microchip's MIPI DSI Controller
wrapper driver that uses the Synopsys DesignWare MIPI DSI host controller
bridge for SAM9X75 SoC series.

Manikandan Muralidharan (4):
  dt-bindings: display: bridge: add sam9x75-mipi-dsi binding
  drm/bridge: add Microchip DSI controller support for sam9x7 SoC series
  MAINTAINERS: add SAM9X7 SoC's Microchip's MIPI DSI host wrapper driver
  ARM: configs: at91: Enable Microchip's MIPI DSI Host Controller
    support

 .../bridge/microchip,sam9x75-mipi-dsi.yaml    | 135 +++++
 MAINTAINERS                                   |   8 +
 arch/arm/configs/at91_dt_defconfig            |   1 +
 drivers/gpu/drm/bridge/Kconfig                |   8 +
 drivers/gpu/drm/bridge/Makefile               |   1 +
 drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c     | 544 ++++++++++++++++++
 6 files changed, 697 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
 create mode 100644 drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c

-- 
2.25.1

[PATCH 1/4] dt-bindings: display: bridge: add sam9x75-mipi-dsi binding

[Manikandan Muralidharan]

Add the 'sam9x75-mipi-dsi' compatible binding, which describes the
Microchip's specific wrapper for the Synopsys DesignWare MIPI DSI HOST
Controller for the sam9x75 series System-on-Chip (SoC) devices.

Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
---
 .../bridge/microchip,sam9x75-mipi-dsi.yaml    | 135 ++++++++++++++++++
 1 file changed, 135 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml

diff --git a/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
new file mode 100644
index 000000000000..87aaf9c929e9
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
@@ -0,0 +1,135 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/bridge/microchip,sam9x75-mipi-dsi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip SAM9X75 MIPI DSI Controller
+
+maintainers:
+  - Manikandan Muralidharan <manikandan.m@microchip.com>
+
+description:
+  Microchip specific extensions or wrapper to the Synopsys Designware MIPI DSI.
+  The MIPI Display Serial Interface (DSI) Host Controller implements all
+  protocol functions defined in the MIPI DSI Specification. The DSI Host
+  provides an interface between the LCD Controller (LCDC) and the MIPI D-PHY,
+  allowing communication with a DSI-compliant display.
+
+allOf:
+  - $ref: /schemas/display/dsi-controller.yaml#
+
+properties:
+  compatible:
+    const: microchip,sam9x75-mipi-dsi
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    description:
+      MIPI DSI must have two clocks to function correctly.Peripheral clock
+      'pclk' for the hardware block functionality and Generic clock 'refclk' to
+      drive the D-PHY PLL block.
+    minItems: 2
+
+  clock-names:
+    items:
+      - const: pclk
+      - const: refclk
+
+  microchip,sfr:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      phandle to Special Function Register (SFR) node.To enable the DSI/CSI
+      selection bit in SFR's ISS Configuration Register.
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/$defs/port-base
+        unevaluatedProperties: false
+        description:
+          DSI Input port node, connected to the LCDC RGB output port.
+
+        properties:
+          endpoint:
+            $ref: /schemas/media/video-interfaces.yaml#
+            unevaluatedProperties: false
+            properties:
+              remote-endpoint: true
+
+      port@1:
+        $ref: /schemas/graph.yaml#/$defs/port-base
+        unevaluatedProperties: false
+        description:
+          DSI Output port node, connected to a panel or a bridge input port.
+
+        properties:
+          endpoint:
+            $ref: /schemas/media/video-interfaces.yaml#
+            unevaluatedProperties: false
+            properties:
+              remote-endpoint: true
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - ports
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/at91.h>
+    #include <dt-bindings/gpio/gpio.h>
+
+    dsi: dsi@f8054000 {
+         compatible = "microchip,sam9x75-mipi-dsi";
+         reg = <0xf8054000 0x200>;
+         clocks = <&pmc PMC_TYPE_PERIPHERAL 54>, <&pmc PMC_TYPE_GCK 55>;
+         clock-names = "pclk", "refclk";
+         microchip,sfr = <&sfr>;
+
+         #address-cells = <1>;
+         #size-cells = <0>;
+
+         ports {
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                port@0 {
+                        reg = <0>;
+                        dsi_in: endpoint {
+                            remote-endpoint = <&hlcdc_panel_output>;
+                        };
+                };
+
+                port@1 {
+                        reg = <1>;
+                        dsi_out: endpoint {
+                            remote-endpoint = <&mipi_in_panel>;
+                        };
+                };
+         };
+
+         panel@0 {
+              compatible = "hannstar,hsd060bhw4", "himax,hx8394";
+              reg = <0>;
+              vcc-supply = <&mic23150_reg>;
+              iovcc-supply = <&mic23150_reg>;
+              reset-gpios = <&pioC 24 GPIO_ACTIVE_LOW>;
+              backlight = <&backlight>;
+
+              port {
+                   mipi_in_panel: endpoint {
+                        remote-endpoint = <&dsi_out>;
+                   };
+              };
+         };
+    };
+...
-- 
2.25.1

[PATCH 2/4] drm/bridge: add Microchip DSI controller support for sam9x7 SoC series

[Manikandan Muralidharan]

Add the Microchip's DSI controller wrapper driver that uses
the Synopsys DesignWare MIPI DSI host controller bridge.

Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
---
 drivers/gpu/drm/bridge/Kconfig            |   8 +
 drivers/gpu/drm/bridge/Makefile           |   1 +
 drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c | 544 ++++++++++++++++++++++
 3 files changed, 553 insertions(+)
 create mode 100644 drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index c621be1a99a8..459ad9768234 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -196,6 +196,14 @@ config DRM_MICROCHIP_LVDS_SERIALIZER
 	help
 	  Support for Microchip's LVDS serializer.
 
+config DRM_MICROCHIP_DW_MIPI_DSI
+	tristate "Microchip specific extensions for Synopsys DW MIPI DSI"
+	depends on DRM_ATMEL_HLCDC
+	select DRM_DW_MIPI_DSI
+	help
+	  This selects support for Microchip's SoC specific extensions
+	  for the Synopsys DesignWare dsi driver.
+
 config DRM_NWL_MIPI_DSI
 	tristate "Northwest Logic MIPI DSI Host controller"
 	depends on DRM
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index 7df87b582dca..aff5052100b9 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_DRM_LONTIUM_LT9611UXC) += lontium-lt9611uxc.o
 obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o
 obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += megachips-stdpxxxx-ge-b850v3-fw.o
 obj-$(CONFIG_DRM_MICROCHIP_LVDS_SERIALIZER) += microchip-lvds.o
+obj-$(CONFIG_DRM_MICROCHIP_DW_MIPI_DSI) += dw-mipi-dsi-mchp.o
 obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
 obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
 obj-$(CONFIG_DRM_PARADE_PS8640) += parade-ps8640.o
diff --git a/drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c b/drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c
new file mode 100644
index 000000000000..d2c4525677ab
--- /dev/null
+++ b/drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c
@@ -0,0 +1,544 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2024 Microchip Technology Inc. and its subsidiaries
+ *
+ * Author: Manikandan Muralidharan <manikandan.m@microchip.com>
+ *
+ */
+
+#include <drm/bridge/dw_mipi_dsi.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_print.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mod_devicetable.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/of.h>
+
+#define DSI_PLL_REF_CLK			24000000
+
+#define DSI_PWR_UP			0x04
+#define HOST_RESET			BIT(0)
+#define HOST_PWRUP			0
+
+#define DSI_PHY_RSTZ			0xa0
+#define PHY_SHUTDOWNZ			0
+
+#define DSI_PHY_TST_CTRL0		0xb4
+#define PHY_TESTCLK			BIT(1)
+#define PHY_UNTESTCLK			0
+#define PHY_TESTCLR			BIT(0)
+#define PHY_UNTESTCLR			0
+
+#define DSI_PHY_TST_CTRL1		0xb8
+#define PHY_TESTEN			BIT(16)
+#define PHY_UNTESTEN			0
+#define PHY_TESTDOUT(n)			(((n) & 0xff) << 8)
+#define PHY_TESTDIN(n)			(((n) & 0xff) << 0)
+
+#define BYPASS_VCO_RANGE		BIT(7)
+#define VCO_RANGE_CON_SEL(val)		(((val) & 0x7) << 3)
+#define VCO_IN_CAP_CON_LOW		BIT(1)
+
+#define CP_CURRENT_0			0x2
+#define CP_CURRENT_1			0x4
+#define CP_CURRENT_2			0x5
+#define CP_CURRENT_3			0x6
+#define CP_CURRENT_4			0x7
+#define CP_CURRENT_5			0x8
+#define CP_CURRENT_6			0xc
+#define CP_CURRENT_SEL(val)		((val) & 0xf)
+#define CP_PROGRAM_EN			BIT(7)
+
+#define LPF_RESISTORS_18KOHM		0x0
+#define LPF_RESISTORS_15_6KOHM		0x1
+#define LPF_RESISTORS_15KOHM		0x2
+#define LPF_RESISTORS_14_4KOHM		0x4
+#define LPF_RESISTORS_12_8KOHM		0x8
+#define LPF_RESISTORS_11_4KOHM		0x10
+#define LPF_RESISTORS_10_5KOHM		0x20
+#define LPF_PROGRAM_EN			BIT(6)
+#define LPF_RESISTORS_SEL(val)		((val) & 0x3f)
+
+#define HSFREQRANGE_SEL(val)		(((val) & 0x3f) << 1)
+
+#define INPUT_DIVIDER(val)		(((val) - 1) & 0x7f)
+#define LOW_PROGRAM_EN			0
+#define HIGH_PROGRAM_EN			BIT(7)
+#define LOOP_DIV_LOW_SEL(val)		(((val) - 1) & 0x1f)
+#define LOOP_DIV_HIGH_SEL(val)		((((val) - 1) >> 5) & 0xf)
+#define PLL_LOOP_DIV_EN			BIT(5)
+#define PLL_INPUT_DIV_EN		BIT(4)
+
+#define PLL_BIAS_CUR_SEL_CAP_VCO_CONTROL		0x10
+#define PLL_CP_CONTROL_PLL_LOCK_BYPASS			0x11
+#define PLL_LPF_AND_CP_CONTROL				0x12
+#define PLL_INPUT_DIVIDER_RATIO				0x17
+#define PLL_LOOP_DIVIDER_RATIO				0x18
+#define PLL_INPUT_AND_LOOP_DIVIDER_RATIOS_CONTROL	0x19
+
+#define SFR_ISS_CFG			0x240
+#define ISS_CFG_DSI_MODE		1
+
+struct dw_mipi_dsi_mchp_chip_data {
+	unsigned int max_data_lanes;
+	struct dw_mipi_dsi_phy_ops *phy_ops;
+};
+
+struct dw_mipi_dsi_mchp {
+	struct device *dev;
+	void __iomem *base;
+	struct dw_mipi_dsi_plat_data pdata;
+	struct dw_mipi_dsi *dsi;
+
+	/* needed for PLL config */
+	unsigned int lane_mbps;
+	u16 input_div;
+	u16 feedback_div;
+	u32 format;
+
+	struct clk *pclk;
+	struct clk *pllref_clk;
+};
+
+struct dphy_pll_parameter_map {
+	unsigned int max_mbps;
+	u8 hsfreqrange;
+	u8 icpctrl;
+	u8 lpfctrl;
+};
+
+static const struct dphy_pll_parameter_map dppa_map[] = {
+	{  89, 0x00, CP_CURRENT_1, LPF_RESISTORS_11_4KOHM },
+	{  99, 0x20, CP_CURRENT_1, LPF_RESISTORS_11_4KOHM },
+	{ 109, 0x40, CP_CURRENT_1, LPF_RESISTORS_11_4KOHM },
+	{ 129, 0x02, CP_CURRENT_5, LPF_RESISTORS_12_8KOHM },
+	{ 139, 0x22, CP_CURRENT_5, LPF_RESISTORS_12_8KOHM },
+	{ 149, 0x42, CP_CURRENT_5, LPF_RESISTORS_12_8KOHM },
+	{ 169, 0x04, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
+	{ 179, 0x24, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
+	{ 199, 0x44, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
+	{ 219, 0x06, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
+	{ 239, 0x26, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
+	{ 249, 0x46, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
+	{ 269, 0x08, CP_CURRENT_0, LPF_RESISTORS_12_8KOHM },
+	{ 299, 0x28, CP_CURRENT_0, LPF_RESISTORS_12_8KOHM },
+	{ 329, 0x0a, CP_CURRENT_2, LPF_RESISTORS_12_8KOHM },
+	{ 359, 0x2a, CP_CURRENT_2, LPF_RESISTORS_12_8KOHM },
+	{ 399, 0x4a, CP_CURRENT_2, LPF_RESISTORS_12_8KOHM },
+	{ 449, 0x0C, CP_CURRENT_2, LPF_RESISTORS_15_6KOHM },
+	{ 499, 0x2c, CP_CURRENT_2, LPF_RESISTORS_15_6KOHM },
+	{ 549, 0x0e, CP_CURRENT_3, LPF_RESISTORS_11_4KOHM },
+	{ 599, 0x2e, CP_CURRENT_3, LPF_RESISTORS_11_4KOHM },
+	{ 649, 0x10, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
+	{ 699, 0x30, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
+	{ 749, 0x12, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
+	{ 799, 0x32, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
+	{ 849, 0x52, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
+	{ 899, 0x72, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
+	{ 949, 0x14, CP_CURRENT_4, LPF_RESISTORS_11_4KOHM },
+	{1000, 0x34, CP_CURRENT_4, LPF_RESISTORS_11_4KOHM }
+};
+
+struct hstt {
+	unsigned int maxfreq;
+	struct dw_mipi_dsi_dphy_timing timing;
+};
+
+#define HSTT(_maxfreq, _c_lp2hs, _c_hs2lp, _d_lp2hs, _d_hs2lp)	\
+{					\
+	.maxfreq = _maxfreq,		\
+	.timing = {			\
+		.clk_lp2hs = _c_lp2hs,	\
+		.clk_hs2lp = _c_hs2lp,	\
+		.data_lp2hs = _d_lp2hs,	\
+		.data_hs2lp = _d_hs2lp,	\
+	}				\
+}
+
+struct hstt hstt_table[] = {
+	HSTT(90,  32, 20,  26, 13),
+	HSTT(100,  35, 23,  28, 14),
+	HSTT(110,  32, 22,  26, 13),
+	HSTT(130,  31, 20,  27, 13),
+	HSTT(140,  33, 22,  26, 14),
+	HSTT(150,  33, 21,  26, 14),
+	HSTT(170,  32, 20,  27, 13),
+	HSTT(180,  36, 23,  30, 15),
+	HSTT(200,  40, 22,  33, 15),
+	HSTT(220,  40, 22,  33, 15),
+	HSTT(240,  44, 24,  36, 16),
+	HSTT(250,  48, 24,  38, 17),
+	HSTT(270,  48, 24,  38, 17),
+	HSTT(300,  50, 27,  41, 18),
+	HSTT(330,  56, 28,  45, 18),
+	HSTT(360,  59, 28,  48, 19),
+	HSTT(400,  61, 30,  50, 20),
+	HSTT(450,  67, 31,  55, 21),
+	HSTT(500,  73, 31,  59, 22),
+	HSTT(550,  79, 36,  63, 24),
+	HSTT(600,  83, 37,  68, 25),
+	HSTT(650,  90, 38,  73, 27),
+	HSTT(700,  95, 40,  77, 28),
+	HSTT(750, 102, 40,  84, 28),
+	HSTT(800, 106, 42,  87, 30),
+	HSTT(850, 113, 44,  93, 31),
+	HSTT(900, 118, 47,  98, 32),
+	HSTT(950, 124, 47, 102, 34),
+	HSTT(1000, 130, 49, 107, 35),
+};
+
+static int max_mbps_to_parameter(unsigned int max_mbps)
+{
+	int index;
+
+	for (index = 0; index < ARRAY_SIZE(dppa_map); index++)
+		if (dppa_map[index].max_mbps >= max_mbps)
+			return index;
+
+	return -EINVAL;
+}
+
+static inline void dsi_write(struct dw_mipi_dsi_mchp *dsi, u32 reg, u32 val)
+{
+	writel(val, dsi->base + reg);
+}
+
+static inline u32 dsi_read(struct dw_mipi_dsi_mchp *dsi, u32 reg)
+{
+	return readl(dsi->base + reg);
+}
+
+static void dw_mipi_dsi_phy_write(struct dw_mipi_dsi_mchp *dsi,
+				  u8 test_code,
+				  u8 test_data)
+{
+	/* General DPHY control operation */
+
+	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLK | PHY_UNTESTCLR);
+	dsi_write(dsi, DSI_PHY_TST_CTRL1, PHY_TESTEN | PHY_TESTDOUT(1) |
+						PHY_TESTDIN(test_code));
+	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLK | PHY_UNTESTCLR);
+	dsi_write(dsi, DSI_PHY_TST_CTRL1, PHY_UNTESTEN | PHY_TESTDOUT(0) |
+						PHY_TESTDIN(test_data));
+	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLK | PHY_UNTESTCLR);
+	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLK | PHY_UNTESTCLR);
+}
+
+static int dw_mipi_dsi_mchp_init(void *priv_data)
+{
+	struct dw_mipi_dsi_mchp *dsi = priv_data;
+	int index, vco, ret = 0;
+
+	/*
+	 * Get vco from frequency(lane_mbps)
+	 * vco	frequency table
+	 * 000 - between   80 and  200 MHz
+	 * 001 - between  200 and  300 MHz
+	 * 010 - between  300 and  500 MHz
+	 * 011 - between  500 and  700 MHz
+	 * 100 - between  700 and  900 MHz
+	 * 101 - between  900 and 1000 MHz
+	 */
+	vco = (dsi->lane_mbps < 200) ? 0 : (dsi->lane_mbps + 100) / 200;
+
+	index = max_mbps_to_parameter(dsi->lane_mbps);
+	if (index < 0) {
+		dev_err(dsi->dev,
+			"failed to get parameter for %dmbps clock\n",
+			dsi->lane_mbps);
+		return index;
+	}
+
+	/* D-PHY in Shutdown mode */
+	dsi_write(dsi, DSI_PHY_RSTZ, PHY_SHUTDOWNZ);
+
+	dw_mipi_dsi_phy_write(dsi, PLL_BIAS_CUR_SEL_CAP_VCO_CONTROL,
+			      BYPASS_VCO_RANGE |
+			      VCO_RANGE_CON_SEL(vco) |
+			      VCO_IN_CAP_CON_LOW);
+
+	dw_mipi_dsi_phy_write(dsi, PLL_CP_CONTROL_PLL_LOCK_BYPASS,
+			      CP_CURRENT_SEL(dppa_map[index].icpctrl));
+
+	dw_mipi_dsi_phy_write(dsi, PLL_LPF_AND_CP_CONTROL,
+			      CP_PROGRAM_EN | LPF_PROGRAM_EN |
+			      LPF_RESISTORS_SEL(dppa_map[index].lpfctrl));
+
+	dw_mipi_dsi_phy_write(dsi, PLL_INPUT_AND_LOOP_DIVIDER_RATIOS_CONTROL,
+			      PLL_LOOP_DIV_EN | PLL_INPUT_DIV_EN);
+
+	dw_mipi_dsi_phy_write(dsi, PLL_INPUT_DIVIDER_RATIO,
+			      INPUT_DIVIDER(dsi->input_div));
+
+	dw_mipi_dsi_phy_write(dsi, PLL_LOOP_DIVIDER_RATIO,
+			      LOOP_DIV_LOW_SEL(dsi->feedback_div) |
+			      LOW_PROGRAM_EN);
+
+	dw_mipi_dsi_phy_write(dsi, PLL_LOOP_DIVIDER_RATIO,
+			      LOOP_DIV_HIGH_SEL(dsi->feedback_div) |
+			      HIGH_PROGRAM_EN);
+
+	return ret;
+}
+
+static int dw_mipi_dsi_mchp_get_lane_mbps(void *priv_data,
+					  const struct drm_display_mode *mode,
+					  unsigned long mode_flags, u32 lanes,
+					  u32 format, unsigned int *lane_mbps)
+{
+	struct dw_mipi_dsi_mchp *dsi = priv_data;
+	unsigned long best_freq, fvco_min, fvco_max, fin, fout;
+	unsigned long min_delta = ULONG_MAX, delta;
+	unsigned int mpclk, target_mbps, desired_mbps;
+	unsigned int max_mbps = dppa_map[ARRAY_SIZE(dppa_map) - 1].max_mbps;
+	unsigned int bpp, min_prediv, max_prediv;
+	unsigned int _fbdiv, best_fbdiv, _prediv, best_prediv;
+	u64 freq_factor;
+
+	dsi->format = format;
+	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
+	if (bpp < 0) {
+		dev_err(dsi->dev,
+			"failed to get bpp for pixel format %d\n",
+			dsi->format);
+		return bpp;
+	}
+
+	mpclk = DIV_ROUND_UP(mode->clock, MSEC_PER_SEC);
+	if (mpclk) {
+		/* take 1/0.8, since mbps must be bigger than bandwidth of RGB */
+		desired_mbps = mpclk * (bpp / lanes) * 10 / 8;
+		if (desired_mbps < max_mbps) {
+			target_mbps = desired_mbps;
+		} else {
+			dev_err(dsi->dev,
+				"DPHY clock frequency is out of range\n");
+			return -ERANGE;
+		}
+	}
+
+	fin = clk_get_rate(dsi->pllref_clk);
+	fout = target_mbps * USEC_PER_SEC;
+
+	/* constraint: 5Mhz <= Fref / N <= 40MHz */
+	min_prediv = DIV_ROUND_UP(fin, 40 * USEC_PER_SEC);
+	max_prediv = fin / (5 * USEC_PER_SEC);
+
+	/* constraint: 80MHz <= Fvco <= 1000Mhz */
+	fvco_min = 80 * USEC_PER_SEC;
+	fvco_max = 1000 * USEC_PER_SEC;
+
+	best_freq = 0;
+	for (_prediv = min_prediv; _prediv <= max_prediv; _prediv++) {
+		/* Fvco = Fref * M / N */
+		freq_factor = (uint64_t)fout * _prediv;
+		do_div(freq_factor, fin);
+		_fbdiv = freq_factor;
+		/*
+		 * Due to the use of a "by 2 pre-scaler," the range of the
+		 * feedback multiplication value M is limited to even division
+		 * numbers, and m must be greater than 6, not bigger than 512.
+		 */
+		if (_fbdiv < 6 || _fbdiv > 512)
+			continue;
+
+		_fbdiv += _fbdiv % 2;
+
+		freq_factor = (uint64_t)_fbdiv * fin;
+		do_div(freq_factor, _prediv);
+		if (freq_factor < fvco_min || freq_factor > fvco_max)
+			continue;
+
+		delta = abs(fout - freq_factor);
+		if (delta < min_delta) {
+			best_prediv = _prediv;
+			best_fbdiv = _fbdiv;
+			min_delta = delta;
+			best_freq = freq_factor;
+		}
+	}
+
+	if (best_freq) {
+		dsi->lane_mbps = DIV_ROUND_UP(best_freq, USEC_PER_SEC);
+		*lane_mbps = dsi->lane_mbps;
+		dsi->input_div = best_prediv;
+		dsi->feedback_div = best_fbdiv;
+	} else {
+		dev_err(dsi->dev, "Can not find best_freq for DPHY\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int dw_mipi_dsi_mchp_get_timing(void *priv_data, unsigned int lane_mbps,
+				       struct dw_mipi_dsi_dphy_timing *timing)
+{
+	int index;
+
+	for (index = 0; index < ARRAY_SIZE(hstt_table); index++)
+		if (lane_mbps < hstt_table[index].maxfreq)
+			break;
+
+	if (index == ARRAY_SIZE(hstt_table))
+		index--;
+
+	*timing = hstt_table[index].timing;
+
+	return 0;
+}
+
+static void dw_mipi_dsi_mchp_power_on(void *priv_data)
+{
+	struct dw_mipi_dsi_mchp *dsi = priv_data;
+
+	/* Enable the DSI wrapper */
+	dsi_write(dsi, DSI_PWR_UP, HOST_PWRUP);
+}
+
+static void dw_mipi_dsi_mchp_power_off(void *priv_data)
+{
+	struct dw_mipi_dsi_mchp *dsi = priv_data;
+
+	/* Disable the DSI wrapper */
+	dsi_write(dsi, DSI_PWR_UP, HOST_RESET);
+}
+
+struct dw_mipi_dsi_phy_ops dw_mipi_dsi_mchp_phy_ops = {
+	.init = dw_mipi_dsi_mchp_init,
+	.power_on = dw_mipi_dsi_mchp_power_on,
+	.power_off = dw_mipi_dsi_mchp_power_off,
+	.get_lane_mbps = dw_mipi_dsi_mchp_get_lane_mbps,
+	.get_timing = dw_mipi_dsi_mchp_get_timing,
+};
+
+static int dw_mipi_dsi_mchp_probe(struct platform_device *pdev)
+{
+	struct dw_mipi_dsi_mchp *dsi;
+	struct resource *res;
+	struct regmap *sfr;
+	const struct dw_mipi_dsi_mchp_chip_data *cdata;
+	int ret;
+
+	dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
+	if (!dsi)
+		return -ENOMEM;
+
+	dsi->dev = &pdev->dev;
+	cdata = of_device_get_match_data(dsi->dev);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	dsi->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(dsi->base)) {
+		ret = PTR_ERR(dsi->base);
+		dev_err(dsi->dev, "Unable to get DSI Base address: %d\n", ret);
+		return ret;
+	}
+
+	dsi->pclk = devm_clk_get(&pdev->dev, "pclk");
+	if (IS_ERR(dsi->pclk)) {
+		ret = PTR_ERR(dsi->pclk);
+		dev_err(dsi->dev, "Unable to get pclk: %d\n", ret);
+		return ret;
+	}
+
+	dsi->pllref_clk = devm_clk_get(&pdev->dev, "refclk");
+	if (IS_ERR(dsi->pllref_clk)) {
+		ret = PTR_ERR(dsi->pllref_clk);
+		dev_err(dsi->dev, "Unable to get DSI PHY PLL reference clock: %d\n",
+			ret);
+		return ret;
+	}
+
+	clk_set_rate(dsi->pllref_clk, DSI_PLL_REF_CLK);
+	if (clk_get_rate(dsi->pllref_clk) != DSI_PLL_REF_CLK) {
+		dev_err(dsi->dev, "Failed to set DSI PHY PLL reference clock\n");
+		return -EINVAL;
+	}
+
+	ret = clk_prepare_enable(dsi->pllref_clk);
+	if (ret) {
+		dev_err(dsi->dev, "Failed to enable DSI PHY PLL reference clock: %d\n",
+			ret);
+		return ret;
+	}
+
+	sfr = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "microchip,sfr");
+	if (IS_ERR_OR_NULL(sfr)) {
+		ret = PTR_ERR(sfr);
+		dev_err(dsi->dev, "Failed to get handle on Special Function Register: %d\n",
+			ret);
+		goto err_dsi_probe;
+	}
+	/* Select DSI in SFR's ISS Configuration Register */
+	ret = regmap_write(sfr, SFR_ISS_CFG, ISS_CFG_DSI_MODE);
+	if (ret) {
+		dev_err(dsi->dev, "Failed to enable DSI in SFR ISS configuration register: %d\n",
+			ret);
+		goto err_dsi_probe;
+	}
+
+	dsi->pdata.base = dsi->base;
+	dsi->pdata.max_data_lanes = cdata->max_data_lanes;
+	dsi->pdata.phy_ops = cdata->phy_ops;
+	dsi->pdata.priv_data = dsi;
+	platform_set_drvdata(pdev, dsi);
+
+	/* call synopsis probe */
+	dsi->dsi = dw_mipi_dsi_probe(pdev, &dsi->pdata);
+	if (IS_ERR(dsi->dsi)) {
+		ret = PTR_ERR(dsi->dsi);
+		dev_err(dsi->dev, "Failed to initialize mipi dsi host: %d\n", ret);
+		goto err_dsi_probe;
+	}
+
+	return 0;
+
+err_dsi_probe:
+	clk_disable_unprepare(dsi->pllref_clk);
+
+	return ret;
+}
+
+static int dw_mipi_dsi_mchp_remove(struct platform_device *pdev)
+{
+	struct dw_mipi_dsi_mchp *dsi = platform_get_drvdata(pdev);
+
+	dw_mipi_dsi_remove(dsi->dsi);
+	clk_disable_unprepare(dsi->pllref_clk);
+
+	return 0;
+}
+
+static const struct dw_mipi_dsi_mchp_chip_data sam9x75_chip_data = {
+	.max_data_lanes = 4,
+	.phy_ops = &dw_mipi_dsi_mchp_phy_ops,
+};
+
+static const struct of_device_id dw_mipi_dsi_mchp_dt_ids[] = {
+	{
+	 .compatible	= "microchip,sam9x75-mipi-dsi",
+	 .data		= &sam9x75_chip_data,
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, dw_mipi_dsi_mchp_dt_ids);
+
+struct platform_driver dw_mipi_dsi_mchp_driver = {
+	.probe		= dw_mipi_dsi_mchp_probe,
+	.remove		= dw_mipi_dsi_mchp_remove,
+	.driver		= {
+		.of_match_table = dw_mipi_dsi_mchp_dt_ids,
+		.name		= "dw-mipi-dsi-mchp",
+	},
+};
+module_platform_driver(dw_mipi_dsi_mchp_driver);
+
+MODULE_AUTHOR("Manikandan Muralidharan <manikandan.m@microchip.com>");
+MODULE_DESCRIPTION("Microchip DW MIPI DSI controller wrapper driver");
+MODULE_LICENSE("GPL");
-- 
2.25.1

[PATCH 3/4] MAINTAINERS: add SAM9X7 SoC's Microchip's MIPI DSI host wrapper driver

[Manikandan Muralidharan]

Add the Microchip's DSI controller wrapper driver that uses the
Synopsys DesignWare MIPI DSI host controller bridge for the SAM9X7
SoC series to the MAINTAINERS entry.

Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
---
 MAINTAINERS | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index f2d8bc44bb52..a814636e8cf2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14839,6 +14839,14 @@ S:	Supported
 F:	Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-lvds.yaml
 F:	drivers/gpu/drm/bridge/microchip-lvds.c
 
+DRM DRIVER FOR MICROCHIP SAM9X7-COMPATIBLE MIPI DSI HOST CONTROLLER
+M:	Manikandan Muralidharan <manikandan.m@microchip.com>
+L:	dri-devel@lists.freedesktop.org
+S:	Supported
+T:	git git://anongit.freedesktop.org/drm/drm-misc
+F:	Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
+F:	drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c
+
 MICROCHIP SAMA5D2-COMPATIBLE ADC DRIVER
 M:	Eugen Hristev <eugen.hristev@microchip.com>
 L:	linux-iio@vger.kernel.org
-- 
2.25.1

[PATCH 4/4] ARM: configs: at91: Enable Microchip's MIPI DSI Host Controller support

[Manikandan Muralidharan]

Enable the Microchip's DSI controller wrapper driver that uses
the Synopsys DesignWare MIPI DSI host controller bridge.

Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
---
 arch/arm/configs/at91_dt_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/at91_dt_defconfig b/arch/arm/configs/at91_dt_defconfig
index 1d53aec4c836..c5c8623f1075 100644
--- a/arch/arm/configs/at91_dt_defconfig
+++ b/arch/arm/configs/at91_dt_defconfig
@@ -143,6 +143,7 @@ CONFIG_VIDEO_OV2640=m
 CONFIG_VIDEO_OV7740=m
 CONFIG_DRM=y
 CONFIG_DRM_ATMEL_HLCDC=y
+CONFIG_DRM_MICROCHIP_DW_MIPI_DSI=y
 CONFIG_DRM_PANEL_SIMPLE=y
 CONFIG_DRM_PANEL_EDP=y
 CONFIG_FB_ATMEL=y
-- 
2.25.1

Re: [PATCH 3/4] MAINTAINERS: add SAM9X7 SoC's Microchip's MIPI DSI host wrapper driver

[Krzysztof Kozlowski]

On 04/07/2024 10:48, Manikandan Muralidharan wrote:
> Add the Microchip's DSI controller wrapper driver that uses the
> Synopsys DesignWare MIPI DSI host controller bridge for the SAM9X7
> SoC series to the MAINTAINERS entry.
> 
> Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
> ---
>  MAINTAINERS | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index f2d8bc44bb52..a814636e8cf2 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -14839,6 +14839,14 @@ S:	Supported
>  F:	Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-lvds.yaml
>  F:	drivers/gpu/drm/bridge/microchip-lvds.c
>  
> +DRM DRIVER FOR MICROCHIP SAM9X7-COMPATIBLE MIPI DSI HOST CONTROLLER
> +M:	Manikandan Muralidharan <manikandan.m@microchip.com>
> +L:	dri-devel@lists.freedesktop.org
> +S:	Supported
> +T:	git git://anongit.freedesktop.org/drm/drm-misc

Do you have commit rights to above repo? If not, drop the T:.

Best regards,
Krzysztof

Re: [PATCH 1/4] dt-bindings: display: bridge: add sam9x75-mipi-dsi binding

[Krzysztof Kozlowski]

On 04/07/2024 10:48, Manikandan Muralidharan wrote:
> Add the 'sam9x75-mipi-dsi' compatible binding, which describes the
> Microchip's specific wrapper for the Synopsys DesignWare MIPI DSI HOST
> Controller for the sam9x75 series System-on-Chip (SoC) devices.
> 
> Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
> ---
>  .../bridge/microchip,sam9x75-mipi-dsi.yaml    | 135 ++++++++++++++++++
>  1 file changed, 135 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
> new file mode 100644
> index 000000000000..87aaf9c929e9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
> @@ -0,0 +1,135 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/bridge/microchip,sam9x75-mipi-dsi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Microchip SAM9X75 MIPI DSI Controller
> +
> +maintainers:
> +  - Manikandan Muralidharan <manikandan.m@microchip.com>
> +
> +description:
> +  Microchip specific extensions or wrapper to the Synopsys Designware MIPI DSI.
> +  The MIPI Display Serial Interface (DSI) Host Controller implements all
> +  protocol functions defined in the MIPI DSI Specification. The DSI Host
> +  provides an interface between the LCD Controller (LCDC) and the MIPI D-PHY,
> +  allowing communication with a DSI-compliant display.
> +
> +allOf:
> +  - $ref: /schemas/display/dsi-controller.yaml#
> +
> +properties:
> +  compatible:
> +    const: microchip,sam9x75-mipi-dsi
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    description:
> +      MIPI DSI must have two clocks to function correctly.Peripheral clock
> +      'pclk' for the hardware block functionality and Generic clock 'refclk' to
> +      drive the D-PHY PLL block.

List the clocks with description instead of writing it in free-form text.

> +    minItems: 2

Drop, three clocks would not be correct anyway, right?

> +
> +  clock-names:
> +    items:
> +      - const: pclk
> +      - const: refclk
> +
> +  microchip,sfr:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description:
> +      phandle to Special Function Register (SFR) node.To enable the DSI/CSI

Everywhere: there is always a space after full stop.

> +      selection bit in SFR's ISS Configuration Register.
> +
> +  ports:
> +    $ref: /schemas/graph.yaml#/properties/ports
> +
> +    properties:
> +      port@0:
> +        $ref: /schemas/graph.yaml#/$defs/port-base
> +        unevaluatedProperties: false
> +        description:
> +          DSI Input port node, connected to the LCDC RGB output port.
> +
> +        properties:
> +          endpoint:
> +            $ref: /schemas/media/video-interfaces.yaml#
> +            unevaluatedProperties: false
> +            properties:
> +              remote-endpoint: true

Why do you need it?

No constraints on data-lanes or frequencies?

> +
> +      port@1:
> +        $ref: /schemas/graph.yaml#/$defs/port-base
> +        unevaluatedProperties: false
> +        description:
> +          DSI Output port node, connected to a panel or a bridge input port.
> +
> +        properties:
> +          endpoint:
> +            $ref: /schemas/media/video-interfaces.yaml#
> +            unevaluatedProperties: false
> +            properties:
> +              remote-endpoint: true
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - clock-names
> +  - ports
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/at91.h>
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    dsi: dsi@f8054000 {

Drop unused label.

> +         compatible = "microchip,sam9x75-mipi-dsi";
> +         reg = <0xf8054000 0x200>;
> +         clocks = <&pmc PMC_TYPE_PERIPHERAL 54>, <&pmc PMC_TYPE_GCK 55>;
> +         clock-names = "pclk", "refclk";
> +         microchip,sfr = <&sfr>;
> +
> +         #address-cells = <1>;
> +         #size-cells = <0>;
> +
> +         ports {
> +                #address-cells = <1>;

Messed indentation, everywhere in the example...

Use 4 spaces for example indentation.

> +                #size-cells = <0>;
> +
> +                port@0 {
> +                        reg = <0>;
> +                        dsi_in: endpoint {
> +                            remote-endpoint = <&hlcdc_panel_output>;
> +                        };
> +                };
> +
> +                port@1 {
> +                        reg = <1>;
> +                        dsi_out: endpoint {
> +                            remote-endpoint = <&mipi_in_panel>;
> +                        };
> +                };
> +         };
> +
> +         panel@0 {

Drop the node, not related.

Best regards,
Krzysztof

Re: [PATCH 2/4] drm/bridge: add Microchip DSI controller support for sam9x7 SoC series

[Krzysztof Kozlowski]

On 04/07/2024 10:48, Manikandan Muralidharan wrote:
> Add the Microchip's DSI controller wrapper driver that uses
> the Synopsys DesignWare MIPI DSI host controller bridge.
> 
> Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
> ---


...

> +
> +#define HSTT(_maxfreq, _c_lp2hs, _c_hs2lp, _d_lp2hs, _d_hs2lp)	\
> +{					\
> +	.maxfreq = _maxfreq,		\
> +	.timing = {			\
> +		.clk_lp2hs = _c_lp2hs,	\
> +		.clk_hs2lp = _c_hs2lp,	\
> +		.data_lp2hs = _d_lp2hs,	\
> +		.data_hs2lp = _d_hs2lp,	\
> +	}				\
> +}
> +
> +struct hstt hstt_table[] = {

So more globals? No.

> +	HSTT(90,  32, 20,  26, 13),
> +	HSTT(100,  35, 23,  28, 14),
> +	HSTT(110,  32, 22,  26, 13),
> +	HSTT(130,  31, 20,  27, 13),
> +	HSTT(140,  33, 22,  26, 14),
> +	HSTT(150,  33, 21,  26, 14),
> +	HSTT(170,  32, 20,  27, 13),
> +	HSTT(180,  36, 23,  30, 15),
> +	HSTT(200,  40, 22,  33, 15),
> +	HSTT(220,  40, 22,  33, 15),
> +	HSTT(240,  44, 24,  36, 16),
> +	HSTT(250,  48, 24,  38, 17),
> +	HSTT(270,  48, 24,  38, 17),
> +	HSTT(300,  50, 27,  41, 18),
> +	HSTT(330,  56, 28,  45, 18),
> +	HSTT(360,  59, 28,  48, 19),
> +	HSTT(400,  61, 30,  50, 20),
> +	HSTT(450,  67, 31,  55, 21),
> +	HSTT(500,  73, 31,  59, 22),
> +	HSTT(550,  79, 36,  63, 24),
> +	HSTT(600,  83, 37,  68, 25),
> +	HSTT(650,  90, 38,  73, 27),
> +	HSTT(700,  95, 40,  77, 28),
> +	HSTT(750, 102, 40,  84, 28),
> +	HSTT(800, 106, 42,  87, 30),
> +	HSTT(850, 113, 44,  93, 31),
> +	HSTT(900, 118, 47,  98, 32),
> +	HSTT(950, 124, 47, 102, 34),
> +	HSTT(1000, 130, 49, 107, 35),
> +};
> +

...

> +
> +static void dw_mipi_dsi_mchp_power_on(void *priv_data)
> +{
> +	struct dw_mipi_dsi_mchp *dsi = priv_data;
> +
> +	/* Enable the DSI wrapper */
> +	dsi_write(dsi, DSI_PWR_UP, HOST_PWRUP);
> +}
> +
> +static void dw_mipi_dsi_mchp_power_off(void *priv_data)
> +{
> +	struct dw_mipi_dsi_mchp *dsi = priv_data;
> +
> +	/* Disable the DSI wrapper */
> +	dsi_write(dsi, DSI_PWR_UP, HOST_RESET);
> +}
> +
> +struct dw_mipi_dsi_phy_ops dw_mipi_dsi_mchp_phy_ops = {

Why this is not static?

Why this is not const?

> +	.init = dw_mipi_dsi_mchp_init,
> +	.power_on = dw_mipi_dsi_mchp_power_on,
> +	.power_off = dw_mipi_dsi_mchp_power_off,
> +	.get_lane_mbps = dw_mipi_dsi_mchp_get_lane_mbps,
> +	.get_timing = dw_mipi_dsi_mchp_get_timing,
> +};
> +
> +static int dw_mipi_dsi_mchp_probe(struct platform_device *pdev)
> +{
> +	struct dw_mipi_dsi_mchp *dsi;
> +	struct resource *res;
> +	struct regmap *sfr;
> +	const struct dw_mipi_dsi_mchp_chip_data *cdata;
> +	int ret;
> +
> +	dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
> +	if (!dsi)
> +		return -ENOMEM;
> +
> +	dsi->dev = &pdev->dev;
> +	cdata = of_device_get_match_data(dsi->dev);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	dsi->base = devm_ioremap_resource(&pdev->dev, res);

There is a helper for these two.

> +	if (IS_ERR(dsi->base)) {
> +		ret = PTR_ERR(dsi->base);
> +		dev_err(dsi->dev, "Unable to get DSI Base address: %d\n", ret);

return dev_err_probe

> +		return ret;
> +	}
> +
> +	dsi->pclk = devm_clk_get(&pdev->dev, "pclk");
> +	if (IS_ERR(dsi->pclk)) {
> +		ret = PTR_ERR(dsi->pclk);
> +		dev_err(dsi->dev, "Unable to get pclk: %d\n", ret);

return dev_err_probe

You are upstreaming some old code, aren't you?

> +		return ret;
> +	}
> +
> +	dsi->pllref_clk = devm_clk_get(&pdev->dev, "refclk");
> +	if (IS_ERR(dsi->pllref_clk)) {
> +		ret = PTR_ERR(dsi->pllref_clk);
> +		dev_err(dsi->dev, "Unable to get DSI PHY PLL reference clock: %d\n",

return dev_err_probe


> +			ret);
> +		return ret;
> +	}
> +
> +	clk_set_rate(dsi->pllref_clk, DSI_PLL_REF_CLK);
> +	if (clk_get_rate(dsi->pllref_clk) != DSI_PLL_REF_CLK) {
> +		dev_err(dsi->dev, "Failed to set DSI PHY PLL reference clock\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = clk_prepare_enable(dsi->pllref_clk);

Enable clock later, so your error paths will be simpler.

> +	if (ret) {
> +		dev_err(dsi->dev, "Failed to enable DSI PHY PLL reference clock: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	sfr = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "microchip,sfr");
> +	if (IS_ERR_OR_NULL(sfr)) {

NULL? Can it be NULL?

> +		ret = PTR_ERR(sfr);
> +		dev_err(dsi->dev, "Failed to get handle on Special Function Register: %d\n",
> +			ret);

ret = dev_err_probe

> +		goto err_dsi_probe;
> +	}
> +	/* Select DSI in SFR's ISS Configuration Register */
> +	ret = regmap_write(sfr, SFR_ISS_CFG, ISS_CFG_DSI_MODE);
> +	if (ret) {
> +		dev_err(dsi->dev, "Failed to enable DSI in SFR ISS configuration register: %d\n",
> +			ret);
> +		goto err_dsi_probe;
> +	}



Best regards,
Krzysztof

Re: [PATCH 2/4] drm/bridge: add Microchip DSI controller support for sam9x7 SoC series

[Manikandan.M]

Hi Krzysztof,

On 04/07/24 4:27 pm, Krzysztof Kozlowski wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> On 04/07/2024 10:48, Manikandan Muralidharan wrote:
>> Add the Microchip's DSI controller wrapper driver that uses
>> the Synopsys DesignWare MIPI DSI host controller bridge.
>>
>> Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
>> ---
> 
> 
> ...
> 
>> +
>> +#define HSTT(_maxfreq, _c_lp2hs, _c_hs2lp, _d_lp2hs, _d_hs2lp)       \
>> +{                                    \
>> +     .maxfreq = _maxfreq,            \
>> +     .timing = {                     \
>> +             .clk_lp2hs = _c_lp2hs,  \
>> +             .clk_hs2lp = _c_hs2lp,  \
>> +             .data_lp2hs = _d_lp2hs, \
>> +             .data_hs2lp = _d_hs2lp, \
>> +     }                               \
>> +}
>> +
>> +struct hstt hstt_table[] = {
> 
> So more globals? No.

In the sam9x7 datasheet, the high speed transition time for data and
clock lane at different freq for the DSI controller ranges are tabulated
with constant values.
I referred other similar platforms for the functionality and found 
similar way of implementation,  only a few had equations to derive the 
low power and high speed timings.I am not able to come up with a more 
efficient method. If there is something I am missing, please suggest.
TIA
> 
>> +     HSTT(90,  32, 20,  26, 13),
>> +     HSTT(100,  35, 23,  28, 14),
>> +     HSTT(110,  32, 22,  26, 13),
>> +     HSTT(130,  31, 20,  27, 13),
>> +     HSTT(140,  33, 22,  26, 14),
>> +     HSTT(150,  33, 21,  26, 14),
>> +     HSTT(170,  32, 20,  27, 13),
>> +     HSTT(180,  36, 23,  30, 15),
>> +     HSTT(200,  40, 22,  33, 15),
>> +     HSTT(220,  40, 22,  33, 15),
>> +     HSTT(240,  44, 24,  36, 16),
>> +     HSTT(250,  48, 24,  38, 17),
>> +     HSTT(270,  48, 24,  38, 17),
>> +     HSTT(300,  50, 27,  41, 18),
>> +     HSTT(330,  56, 28,  45, 18),
>> +     HSTT(360,  59, 28,  48, 19),
>> +     HSTT(400,  61, 30,  50, 20),
>> +     HSTT(450,  67, 31,  55, 21),
>> +     HSTT(500,  73, 31,  59, 22),
>> +     HSTT(550,  79, 36,  63, 24),
>> +     HSTT(600,  83, 37,  68, 25),
>> +     HSTT(650,  90, 38,  73, 27),
>> +     HSTT(700,  95, 40,  77, 28),
>> +     HSTT(750, 102, 40,  84, 28),
>> +     HSTT(800, 106, 42,  87, 30),
>> +     HSTT(850, 113, 44,  93, 31),
>> +     HSTT(900, 118, 47,  98, 32),
>> +     HSTT(950, 124, 47, 102, 34),
>> +     HSTT(1000, 130, 49, 107, 35),
>> +};
>> +
> 
> ...
> 
>> +
>> +static void dw_mipi_dsi_mchp_power_on(void *priv_data)
>> +{
>> +     struct dw_mipi_dsi_mchp *dsi = priv_data;
>> +
>> +     /* Enable the DSI wrapper */
>> +     dsi_write(dsi, DSI_PWR_UP, HOST_PWRUP);
>> +}
>> +
>> +static void dw_mipi_dsi_mchp_power_off(void *priv_data)
>> +{
>> +     struct dw_mipi_dsi_mchp *dsi = priv_data;
>> +
>> +     /* Disable the DSI wrapper */
>> +     dsi_write(dsi, DSI_PWR_UP, HOST_RESET);
>> +}
>> +
>> +struct dw_mipi_dsi_phy_ops dw_mipi_dsi_mchp_phy_ops = {
> 
> Why this is not static?
> 
> Why this is not const?
> 
>> +     .init = dw_mipi_dsi_mchp_init,
>> +     .power_on = dw_mipi_dsi_mchp_power_on,
>> +     .power_off = dw_mipi_dsi_mchp_power_off,
>> +     .get_lane_mbps = dw_mipi_dsi_mchp_get_lane_mbps,
>> +     .get_timing = dw_mipi_dsi_mchp_get_timing,
>> +};
>> +
>> +static int dw_mipi_dsi_mchp_probe(struct platform_device *pdev)
>> +{
>> +     struct dw_mipi_dsi_mchp *dsi;
>> +     struct resource *res;
>> +     struct regmap *sfr;
>> +     const struct dw_mipi_dsi_mchp_chip_data *cdata;
>> +     int ret;
>> +
>> +     dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
>> +     if (!dsi)
>> +             return -ENOMEM;
>> +
>> +     dsi->dev = &pdev->dev;
>> +     cdata = of_device_get_match_data(dsi->dev);
>> +
>> +     res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +     dsi->base = devm_ioremap_resource(&pdev->dev, res);
> 
> There is a helper for these two.
> 
>> +     if (IS_ERR(dsi->base)) {
>> +             ret = PTR_ERR(dsi->base);
>> +             dev_err(dsi->dev, "Unable to get DSI Base address: %d\n", ret);
> 
> return dev_err_probe
> 
>> +             return ret;
>> +     }
>> +
>> +     dsi->pclk = devm_clk_get(&pdev->dev, "pclk");
>> +     if (IS_ERR(dsi->pclk)) {
>> +             ret = PTR_ERR(dsi->pclk);
>> +             dev_err(dsi->dev, "Unable to get pclk: %d\n", ret);
> 
> return dev_err_probe
> 
> You are upstreaming some old code, aren't you?
> 
>> +             return ret;
>> +     }
>> +
>> +     dsi->pllref_clk = devm_clk_get(&pdev->dev, "refclk");
>> +     if (IS_ERR(dsi->pllref_clk)) {
>> +             ret = PTR_ERR(dsi->pllref_clk);
>> +             dev_err(dsi->dev, "Unable to get DSI PHY PLL reference clock: %d\n",
> 
> return dev_err_probe
> 
> 
>> +                     ret);
>> +             return ret;
>> +     }
>> +
>> +     clk_set_rate(dsi->pllref_clk, DSI_PLL_REF_CLK);
>> +     if (clk_get_rate(dsi->pllref_clk) != DSI_PLL_REF_CLK) {
>> +             dev_err(dsi->dev, "Failed to set DSI PHY PLL reference clock\n");
>> +             return -EINVAL;
>> +     }
>> +
>> +     ret = clk_prepare_enable(dsi->pllref_clk);
> 
> Enable clock later, so your error paths will be simpler.
> 
>> +     if (ret) {
>> +             dev_err(dsi->dev, "Failed to enable DSI PHY PLL reference clock: %d\n",
>> +                     ret);
>> +             return ret;
>> +     }
>> +
>> +     sfr = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "microchip,sfr");
>> +     if (IS_ERR_OR_NULL(sfr)) {
> 
> NULL? Can it be NULL?
> 
>> +             ret = PTR_ERR(sfr);
>> +             dev_err(dsi->dev, "Failed to get handle on Special Function Register: %d\n",
>> +                     ret);
> 
> ret = dev_err_probe
> 
>> +             goto err_dsi_probe;
>> +     }
>> +     /* Select DSI in SFR's ISS Configuration Register */
>> +     ret = regmap_write(sfr, SFR_ISS_CFG, ISS_CFG_DSI_MODE);
>> +     if (ret) {
>> +             dev_err(dsi->dev, "Failed to enable DSI in SFR ISS configuration register: %d\n",
>> +                     ret);
>> +             goto err_dsi_probe;
>> +     }
> 
> 
> 
> Best regards,
> Krzysztof
> 

-- 
Thanks and Regards,
Manikandan M.

Re: [PATCH 2/4] drm/bridge: add Microchip DSI controller support for sam9x7 SoC series

[Krzysztof Kozlowski]

On 11/07/2024 10:30, Manikandan.M@microchip.com wrote:
> Hi Krzysztof,
> 
> On 04/07/24 4:27 pm, Krzysztof Kozlowski wrote:
>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>
>> On 04/07/2024 10:48, Manikandan Muralidharan wrote:
>>> Add the Microchip's DSI controller wrapper driver that uses
>>> the Synopsys DesignWare MIPI DSI host controller bridge.
>>>
>>> Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
>>> ---
>>
>>
>> ...
>>
>>> +
>>> +#define HSTT(_maxfreq, _c_lp2hs, _c_hs2lp, _d_lp2hs, _d_hs2lp)       \
>>> +{                                    \
>>> +     .maxfreq = _maxfreq,            \
>>> +     .timing = {                     \
>>> +             .clk_lp2hs = _c_lp2hs,  \
>>> +             .clk_hs2lp = _c_hs2lp,  \
>>> +             .data_lp2hs = _d_lp2hs, \
>>> +             .data_hs2lp = _d_hs2lp, \
>>> +     }                               \
>>> +}
>>> +
>>> +struct hstt hstt_table[] = {
>>
>> So more globals? No.
> 
> In the sam9x7 datasheet, the high speed transition time for data and
> clock lane at different freq for the DSI controller ranges are tabulated
> with constant values.
> I referred other similar platforms for the functionality and found 
> similar way of implementation,  only a few had equations to derive the 
> low power and high speed timings.I am not able to come up with a more 
> efficient method. If there is something I am missing, please suggest.
> TIA

Yeah, this should not be a global. Nothing above suggests it.

BTW, no W=1 clang warnings? Are you sure?

Best regards,
Krzysztof

Re: [PATCH 2/4] drm/bridge: add Microchip DSI controller support for sam9x7 SoC series

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 1903 bytes --]

On Thu, Jul 11, 2024 at 11:05:37AM +0200, Krzysztof Kozlowski wrote:
> On 11/07/2024 10:30, Manikandan.M@microchip.com wrote:
> > Hi Krzysztof,
> > 
> > On 04/07/24 4:27 pm, Krzysztof Kozlowski wrote:
> >> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> >>
> >> On 04/07/2024 10:48, Manikandan Muralidharan wrote:
> >>> Add the Microchip's DSI controller wrapper driver that uses
> >>> the Synopsys DesignWare MIPI DSI host controller bridge.
> >>>
> >>> Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
> >>> ---
> >>
> >>
> >> ...
> >>
> >>> +
> >>> +#define HSTT(_maxfreq, _c_lp2hs, _c_hs2lp, _d_lp2hs, _d_hs2lp)       \
> >>> +{                                    \
> >>> +     .maxfreq = _maxfreq,            \
> >>> +     .timing = {                     \
> >>> +             .clk_lp2hs = _c_lp2hs,  \
> >>> +             .clk_hs2lp = _c_hs2lp,  \
> >>> +             .data_lp2hs = _d_lp2hs, \
> >>> +             .data_hs2lp = _d_hs2lp, \
> >>> +     }                               \
> >>> +}
> >>> +
> >>> +struct hstt hstt_table[] = {
> >>
> >> So more globals? No.
> > 
> > In the sam9x7 datasheet, the high speed transition time for data and
> > clock lane at different freq for the DSI controller ranges are tabulated
> > with constant values.
> > I referred other similar platforms for the functionality and found 
> > similar way of implementation,  only a few had equations to derive the 
> > low power and high speed timings.I am not able to come up with a more 
> > efficient method. If there is something I am missing, please suggest.
> > TIA
> 
> Yeah, this should not be a global. Nothing above suggests it.

I think what Krzysztof is suggesting here is use of the static
keyword...

> 
> BTW, no W=1 clang warnings? Are you sure?
> 
> Best regards,
> Krzysztof
> 

[-- Attachment #2: signature.asc --]
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Re: [PATCH 2/4] drm/bridge: add Microchip DSI controller support for sam9x7 SoC series

[Manikandan.M]

On 11/07/24 3:28 pm, Conor Dooley wrote:
> On Thu, Jul 11, 2024 at 11:05:37AM +0200, Krzysztof Kozlowski wrote:
>> On 11/07/2024 10:30,Manikandan.M@microchip.com  wrote:
>>> Hi Krzysztof,
>>>
>>> On 04/07/24 4:27 pm, Krzysztof Kozlowski wrote:
>>>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>>>
>>>> On 04/07/2024 10:48, Manikandan Muralidharan wrote:
>>>>> Add the Microchip's DSI controller wrapper driver that uses
>>>>> the Synopsys DesignWare MIPI DSI host controller bridge.
>>>>>
>>>>> Signed-off-by: Manikandan Muralidharan<manikandan.m@microchip.com>
>>>>> ---
>>>>
>>>> ...
>>>>
>>>>> +
>>>>> +#define HSTT(_maxfreq, _c_lp2hs, _c_hs2lp, _d_lp2hs, _d_hs2lp)       \
>>>>> +{                                    \
>>>>> +     .maxfreq = _maxfreq,            \
>>>>> +     .timing = {                     \
>>>>> +             .clk_lp2hs = _c_lp2hs,  \
>>>>> +             .clk_hs2lp = _c_hs2lp,  \
>>>>> +             .data_lp2hs = _d_lp2hs, \
>>>>> +             .data_hs2lp = _d_hs2lp, \
>>>>> +     }                               \
>>>>> +}
>>>>> +
>>>>> +struct hstt hstt_table[] = {
>>>> So more globals? No.
>>> In the sam9x7 datasheet, the high speed transition time for data and
>>> clock lane at different freq for the DSI controller ranges are tabulated
>>> with constant values.
>>> I referred other similar platforms for the functionality and found
>>> similar way of implementation,  only a few had equations to derive the
>>> low power and high speed timings.I am not able to come up with a more
>>> efficient method. If there is something I am missing, please suggest.
>>> TIA
>> Yeah, this should not be a global. Nothing above suggests it.
> I think what Krzysztof is suggesting here is use of the static
> keyword...
Yes, after looking at the implementation in similar platforms, I did 
find out.
Thank you Conor.
> 
>> BTW, no W=1 clang warnings? Are you sure?
>>
>> Best regards,
>> Krzysztof

-- 
Thanks and Regards,
Manikandan M.

Re: [PATCH 2/4] drm/bridge: add Microchip DSI controller support for sam9x7 SoC series

[claudiu beznea]

On 04.07.2024 11:48, Manikandan Muralidharan wrote:
> Add the Microchip's DSI controller wrapper driver that uses
> the Synopsys DesignWare MIPI DSI host controller bridge.
> 
> Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
> ---
>  drivers/gpu/drm/bridge/Kconfig            |   8 +
>  drivers/gpu/drm/bridge/Makefile           |   1 +
>  drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c | 544 ++++++++++++++++++++++
>  3 files changed, 553 insertions(+)
>  create mode 100644 drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c
> 
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index c621be1a99a8..459ad9768234 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -196,6 +196,14 @@ config DRM_MICROCHIP_LVDS_SERIALIZER
>  	help
>  	  Support for Microchip's LVDS serializer.
>  
> +config DRM_MICROCHIP_DW_MIPI_DSI
> +	tristate "Microchip specific extensions for Synopsys DW MIPI DSI"
> +	depends on DRM_ATMEL_HLCDC
> +	select DRM_DW_MIPI_DSI
> +	help
> +	  This selects support for Microchip's SoC specific extensions
> +	  for the Synopsys DesignWare dsi driver.
> +
>  config DRM_NWL_MIPI_DSI
>  	tristate "Northwest Logic MIPI DSI Host controller"
>  	depends on DRM
> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> index 7df87b582dca..aff5052100b9 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -14,6 +14,7 @@ obj-$(CONFIG_DRM_LONTIUM_LT9611UXC) += lontium-lt9611uxc.o
>  obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o
>  obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += megachips-stdpxxxx-ge-b850v3-fw.o
>  obj-$(CONFIG_DRM_MICROCHIP_LVDS_SERIALIZER) += microchip-lvds.o
> +obj-$(CONFIG_DRM_MICROCHIP_DW_MIPI_DSI) += dw-mipi-dsi-mchp.o
>  obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
>  obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
>  obj-$(CONFIG_DRM_PARADE_PS8640) += parade-ps8640.o
> diff --git a/drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c b/drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c
> new file mode 100644
> index 000000000000..d2c4525677ab
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c
> @@ -0,0 +1,544 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2024 Microchip Technology Inc. and its subsidiaries
> + *
> + * Author: Manikandan Muralidharan <manikandan.m@microchip.com>
> + *
> + */
> +
> +#include <drm/bridge/dw_mipi_dsi.h>
> +#include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_print.h>
> +#include <linux/bits.h>
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/of.h>
> +
> +#define DSI_PLL_REF_CLK			24000000
> +
> +#define DSI_PWR_UP			0x04
> +#define HOST_RESET			BIT(0)
> +#define HOST_PWRUP			0
> +
> +#define DSI_PHY_RSTZ			0xa0
> +#define PHY_SHUTDOWNZ			0
> +
> +#define DSI_PHY_TST_CTRL0		0xb4
> +#define PHY_TESTCLK			BIT(1)
> +#define PHY_UNTESTCLK			0
> +#define PHY_TESTCLR			BIT(0)
> +#define PHY_UNTESTCLR			0
> +
> +#define DSI_PHY_TST_CTRL1		0xb8
> +#define PHY_TESTEN			BIT(16)
> +#define PHY_UNTESTEN			0
> +#define PHY_TESTDOUT(n)			(((n) & 0xff) << 8)
> +#define PHY_TESTDIN(n)			(((n) & 0xff) << 0)

These 2 looks like FIELD_PREP() candidates.

> +
> +#define BYPASS_VCO_RANGE		BIT(7)
> +#define VCO_RANGE_CON_SEL(val)		(((val) & 0x7) << 3)

This, too.

> +#define VCO_IN_CAP_CON_LOW		BIT(1)
> +
> +#define CP_CURRENT_0			0x2
> +#define CP_CURRENT_1			0x4
> +#define CP_CURRENT_2			0x5
> +#define CP_CURRENT_3			0x6
> +#define CP_CURRENT_4			0x7
> +#define CP_CURRENT_5			0x8
> +#define CP_CURRENT_6			0xc
> +#define CP_CURRENT_SEL(val)		((val) & 0xf)

This, too.

> +#define CP_PROGRAM_EN			BIT(7)
> +
> +#define LPF_RESISTORS_18KOHM		0x0
> +#define LPF_RESISTORS_15_6KOHM		0x1
> +#define LPF_RESISTORS_15KOHM		0x2
> +#define LPF_RESISTORS_14_4KOHM		0x4
> +#define LPF_RESISTORS_12_8KOHM		0x8
> +#define LPF_RESISTORS_11_4KOHM		0x10
> +#define LPF_RESISTORS_10_5KOHM		0x20

Some of these are unsused.

> +#define LPF_PROGRAM_EN			BIT(6)
> +#define LPF_RESISTORS_SEL(val)		((val) & 0x3f)

This, too

> +
> +#define HSFREQRANGE_SEL(val)		(((val) & 0x3f) << 1)

Unused

> +
> +#define INPUT_DIVIDER(val)		(((val) - 1) & 0x7f)
> +#define LOW_PROGRAM_EN			0
> +#define HIGH_PROGRAM_EN			BIT(7)
> +#define LOOP_DIV_LOW_SEL(val)		(((val) - 1) & 0x1f)
> +#define LOOP_DIV_HIGH_SEL(val)		((((val) - 1) >> 5) & 0xf)
> +#define PLL_LOOP_DIV_EN			BIT(5)
> +#define PLL_INPUT_DIV_EN		BIT(4)
> +
> +#define PLL_BIAS_CUR_SEL_CAP_VCO_CONTROL		0x10
> +#define PLL_CP_CONTROL_PLL_LOCK_BYPASS			0x11
> +#define PLL_LPF_AND_CP_CONTROL				0x12
> +#define PLL_INPUT_DIVIDER_RATIO				0x17
> +#define PLL_LOOP_DIVIDER_RATIO				0x18
> +#define PLL_INPUT_AND_LOOP_DIVIDER_RATIOS_CONTROL	0x19
> +
> +#define SFR_ISS_CFG			0x240
> +#define ISS_CFG_DSI_MODE		1
> +
> +struct dw_mipi_dsi_mchp_chip_data {
> +	unsigned int max_data_lanes;
> +	struct dw_mipi_dsi_phy_ops *phy_ops;

pointer first to avoid padding, if any.

> +};
> +
> +struct dw_mipi_dsi_mchp {
> +	struct device *dev;
> +	void __iomem *base;
> +	struct dw_mipi_dsi_plat_data pdata;
> +	struct dw_mipi_dsi *dsi;
> +
> +	/* needed for PLL config */
> +	unsigned int lane_mbps;
> +	u16 input_div;
> +	u16 feedback_div;
> +	u32 format;
> +
> +	struct clk *pclk;
> +	struct clk *pllref_clk;

same here.

> +};
> +
> +struct dphy_pll_parameter_map {
> +	unsigned int max_mbps;
> +	u8 hsfreqrange;
> +	u8 icpctrl;
> +	u8 lpfctrl;
> +};
> +
> +static const struct dphy_pll_parameter_map dppa_map[] = {
> +	{  89, 0x00, CP_CURRENT_1, LPF_RESISTORS_11_4KOHM },
> +	{  99, 0x20, CP_CURRENT_1, LPF_RESISTORS_11_4KOHM },
> +	{ 109, 0x40, CP_CURRENT_1, LPF_RESISTORS_11_4KOHM },
> +	{ 129, 0x02, CP_CURRENT_5, LPF_RESISTORS_12_8KOHM },
> +	{ 139, 0x22, CP_CURRENT_5, LPF_RESISTORS_12_8KOHM },
> +	{ 149, 0x42, CP_CURRENT_5, LPF_RESISTORS_12_8KOHM },
> +	{ 169, 0x04, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
> +	{ 179, 0x24, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
> +	{ 199, 0x44, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
> +	{ 219, 0x06, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
> +	{ 239, 0x26, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
> +	{ 249, 0x46, CP_CURRENT_6, LPF_RESISTORS_12_8KOHM },
> +	{ 269, 0x08, CP_CURRENT_0, LPF_RESISTORS_12_8KOHM },
> +	{ 299, 0x28, CP_CURRENT_0, LPF_RESISTORS_12_8KOHM },
> +	{ 329, 0x0a, CP_CURRENT_2, LPF_RESISTORS_12_8KOHM },
> +	{ 359, 0x2a, CP_CURRENT_2, LPF_RESISTORS_12_8KOHM },
> +	{ 399, 0x4a, CP_CURRENT_2, LPF_RESISTORS_12_8KOHM },
> +	{ 449, 0x0C, CP_CURRENT_2, LPF_RESISTORS_15_6KOHM },
> +	{ 499, 0x2c, CP_CURRENT_2, LPF_RESISTORS_15_6KOHM },
> +	{ 549, 0x0e, CP_CURRENT_3, LPF_RESISTORS_11_4KOHM },
> +	{ 599, 0x2e, CP_CURRENT_3, LPF_RESISTORS_11_4KOHM },
> +	{ 649, 0x10, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
> +	{ 699, 0x30, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
> +	{ 749, 0x12, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
> +	{ 799, 0x32, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
> +	{ 849, 0x52, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
> +	{ 899, 0x72, CP_CURRENT_3, LPF_RESISTORS_14_4KOHM },
> +	{ 949, 0x14, CP_CURRENT_4, LPF_RESISTORS_11_4KOHM },
> +	{1000, 0x34, CP_CURRENT_4, LPF_RESISTORS_11_4KOHM }
> +};
> +
> +struct hstt {
> +	unsigned int maxfreq;
> +	struct dw_mipi_dsi_dphy_timing timing;
> +};
> +
> +#define HSTT(_maxfreq, _c_lp2hs, _c_hs2lp, _d_lp2hs, _d_hs2lp)	\
> +{					\
> +	.maxfreq = _maxfreq,		\
> +	.timing = {			\
> +		.clk_lp2hs = _c_lp2hs,	\
> +		.clk_hs2lp = _c_hs2lp,	\
> +		.data_lp2hs = _d_lp2hs,	\
> +		.data_hs2lp = _d_hs2lp,	\
> +	}				\
> +}
> +
> +struct hstt hstt_table[] = {

static const

> +	HSTT(90,  32, 20,  26, 13),
> +	HSTT(100,  35, 23,  28, 14),
> +	HSTT(110,  32, 22,  26, 13),
> +	HSTT(130,  31, 20,  27, 13),
> +	HSTT(140,  33, 22,  26, 14),
> +	HSTT(150,  33, 21,  26, 14),
> +	HSTT(170,  32, 20,  27, 13),
> +	HSTT(180,  36, 23,  30, 15),
> +	HSTT(200,  40, 22,  33, 15),
> +	HSTT(220,  40, 22,  33, 15),
> +	HSTT(240,  44, 24,  36, 16),
> +	HSTT(250,  48, 24,  38, 17),
> +	HSTT(270,  48, 24,  38, 17),
> +	HSTT(300,  50, 27,  41, 18),
> +	HSTT(330,  56, 28,  45, 18),
> +	HSTT(360,  59, 28,  48, 19),
> +	HSTT(400,  61, 30,  50, 20),
> +	HSTT(450,  67, 31,  55, 21),
> +	HSTT(500,  73, 31,  59, 22),
> +	HSTT(550,  79, 36,  63, 24),
> +	HSTT(600,  83, 37,  68, 25),
> +	HSTT(650,  90, 38,  73, 27),
> +	HSTT(700,  95, 40,  77, 28),
> +	HSTT(750, 102, 40,  84, 28),
> +	HSTT(800, 106, 42,  87, 30),
> +	HSTT(850, 113, 44,  93, 31),
> +	HSTT(900, 118, 47,  98, 32),
> +	HSTT(950, 124, 47, 102, 34),
> +	HSTT(1000, 130, 49, 107, 35),
> +};
> +
> +static int max_mbps_to_parameter(unsigned int max_mbps)
> +{
> +	int index;
> +
> +	for (index = 0; index < ARRAY_SIZE(dppa_map); index++)
> +		if (dppa_map[index].max_mbps >= max_mbps)
> +			return index;
> +
> +	return -EINVAL;
> +}
> +
> +static inline void dsi_write(struct dw_mipi_dsi_mchp *dsi, u32 reg, u32 val)

The name here looks too generic, prefixing it with something like mchp may
be better to avoid any potential conflict. Valid for the rest of functions
in this file.

> +{
> +	writel(val, dsi->base + reg);
> +}
> +
> +static inline u32 dsi_read(struct dw_mipi_dsi_mchp *dsi, u32 reg)
> +{
> +	return readl(dsi->base + reg);
> +}
> +
> +static void dw_mipi_dsi_phy_write(struct dw_mipi_dsi_mchp *dsi,
> +				  u8 test_code,
> +				  u8 test_data)
> +{
> +	/* General DPHY control operation */
> +
> +	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLK | PHY_UNTESTCLR);
> +	dsi_write(dsi, DSI_PHY_TST_CTRL1, PHY_TESTEN | PHY_TESTDOUT(1) |
> +						PHY_TESTDIN(test_code));
> +	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLK | PHY_UNTESTCLR);
> +	dsi_write(dsi, DSI_PHY_TST_CTRL1, PHY_UNTESTEN | PHY_TESTDOUT(0) |
> +						PHY_TESTDIN(test_data));
> +	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLK | PHY_UNTESTCLR);
> +	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLK | PHY_UNTESTCLR);
> +}
> +
> +static int dw_mipi_dsi_mchp_init(void *priv_data)
> +{
> +	struct dw_mipi_dsi_mchp *dsi = priv_data;
> +	int index, vco, ret = 0;
> +
> +	/*
> +	 * Get vco from frequency(lane_mbps)
> +	 * vco	frequency table
> +	 * 000 - between   80 and  200 MHz
> +	 * 001 - between  200 and  300 MHz
> +	 * 010 - between  300 and  500 MHz
> +	 * 011 - between  500 and  700 MHz
> +	 * 100 - between  700 and  900 MHz
> +	 * 101 - between  900 and 1000 MHz
> +	 */
> +	vco = (dsi->lane_mbps < 200) ? 0 : (dsi->lane_mbps + 100) / 200;
> +
> +	index = max_mbps_to_parameter(dsi->lane_mbps);
> +	if (index < 0) {
> +		dev_err(dsi->dev,
> +			"failed to get parameter for %dmbps clock\n",
> +			dsi->lane_mbps);
> +		return index;
> +	}
> +
> +	/* D-PHY in Shutdown mode */
> +	dsi_write(dsi, DSI_PHY_RSTZ, PHY_SHUTDOWNZ);
> +
> +	dw_mipi_dsi_phy_write(dsi, PLL_BIAS_CUR_SEL_CAP_VCO_CONTROL,
> +			      BYPASS_VCO_RANGE |
> +			      VCO_RANGE_CON_SEL(vco) |
> +			      VCO_IN_CAP_CON_LOW);
> +
> +	dw_mipi_dsi_phy_write(dsi, PLL_CP_CONTROL_PLL_LOCK_BYPASS,
> +			      CP_CURRENT_SEL(dppa_map[index].icpctrl));
> +
> +	dw_mipi_dsi_phy_write(dsi, PLL_LPF_AND_CP_CONTROL,
> +			      CP_PROGRAM_EN | LPF_PROGRAM_EN |
> +			      LPF_RESISTORS_SEL(dppa_map[index].lpfctrl));
> +
> +	dw_mipi_dsi_phy_write(dsi, PLL_INPUT_AND_LOOP_DIVIDER_RATIOS_CONTROL,
> +			      PLL_LOOP_DIV_EN | PLL_INPUT_DIV_EN);
> +
> +	dw_mipi_dsi_phy_write(dsi, PLL_INPUT_DIVIDER_RATIO,
> +			      INPUT_DIVIDER(dsi->input_div));
> +
> +	dw_mipi_dsi_phy_write(dsi, PLL_LOOP_DIVIDER_RATIO,
> +			      LOOP_DIV_LOW_SEL(dsi->feedback_div) |
> +			      LOW_PROGRAM_EN);
> +
> +	dw_mipi_dsi_phy_write(dsi, PLL_LOOP_DIVIDER_RATIO,
> +			      LOOP_DIV_HIGH_SEL(dsi->feedback_div) |
> +			      HIGH_PROGRAM_EN);
> +
> +	return ret;
> +}
> +
> +static int dw_mipi_dsi_mchp_get_lane_mbps(void *priv_data,
> +					  const struct drm_display_mode *mode,
> +					  unsigned long mode_flags, u32 lanes,
> +					  u32 format, unsigned int *lane_mbps)
> +{
> +	struct dw_mipi_dsi_mchp *dsi = priv_data;
> +	unsigned long best_freq, fvco_min, fvco_max, fin, fout;
> +	unsigned long min_delta = ULONG_MAX, delta;
> +	unsigned int mpclk, target_mbps, desired_mbps;
> +	unsigned int max_mbps = dppa_map[ARRAY_SIZE(dppa_map) - 1].max_mbps;
> +	unsigned int bpp, min_prediv, max_prediv;
> +	unsigned int _fbdiv, best_fbdiv, _prediv, best_prediv;
> +	u64 freq_factor;
> +
> +	dsi->format = format;
> +	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> +	if (bpp < 0) {
> +		dev_err(dsi->dev,
> +			"failed to get bpp for pixel format %d\n",
> +			dsi->format);
> +		return bpp;
> +	}
> +
> +	mpclk = DIV_ROUND_UP(mode->clock, MSEC_PER_SEC);
> +	if (mpclk) {
> +		/* take 1/0.8, since mbps must be bigger than bandwidth of RGB */
> +		desired_mbps = mpclk * (bpp / lanes) * 10 / 8;
> +		if (desired_mbps < max_mbps) {
> +			target_mbps = desired_mbps;
> +		} else {
> +			dev_err(dsi->dev,
> +				"DPHY clock frequency is out of range\n");
> +			return -ERANGE;
> +		}
> +	}
> +
> +	fin = clk_get_rate(dsi->pllref_clk);
> +	fout = target_mbps * USEC_PER_SEC;
> +
> +	/* constraint: 5Mhz <= Fref / N <= 40MHz */
> +	min_prediv = DIV_ROUND_UP(fin, 40 * USEC_PER_SEC);
> +	max_prediv = fin / (5 * USEC_PER_SEC);
> +
> +	/* constraint: 80MHz <= Fvco <= 1000Mhz */
> +	fvco_min = 80 * USEC_PER_SEC;
> +	fvco_max = 1000 * USEC_PER_SEC;
> +
> +	best_freq = 0;

Could be added to the initialization list of for()

> +	for (_prediv = min_prediv; _prediv <= max_prediv; _prediv++) {
> +		/* Fvco = Fref * M / N */
> +		freq_factor = (uint64_t)fout * _prediv;

u64?

> +		do_div(freq_factor, fin);
> +		_fbdiv = freq_factor;
> +		/*
> +		 * Due to the use of a "by 2 pre-scaler," the range of the
> +		 * feedback multiplication value M is limited to even division
> +		 * numbers, and m must be greater than 6, not bigger than 512.
> +		 */
> +		if (_fbdiv < 6 || _fbdiv > 512)
> +			continue;
> +
> +		_fbdiv += _fbdiv % 2;
> +
> +		freq_factor = (uint64_t)_fbdiv * fin;

u64?

> +		do_div(freq_factor, _prediv);
> +		if (freq_factor < fvco_min || freq_factor > fvco_max)
> +			continue;
> +
> +		delta = abs(fout - freq_factor);
> +		if (delta < min_delta) {
> +			best_prediv = _prediv;
> +			best_fbdiv = _fbdiv;
> +			min_delta = delta;
> +			best_freq = freq_factor;
> +		}
> +	}
> +
> +	if (best_freq) {
> +		dsi->lane_mbps = DIV_ROUND_UP(best_freq, USEC_PER_SEC);
> +		*lane_mbps = dsi->lane_mbps;
> +		dsi->input_div = best_prediv;
> +		dsi->feedback_div = best_fbdiv;
> +	} else {
> +		dev_err(dsi->dev, "Can not find best_freq for DPHY\n");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int dw_mipi_dsi_mchp_get_timing(void *priv_data, unsigned int lane_mbps,
> +				       struct dw_mipi_dsi_dphy_timing *timing)
> +{
> +	int index;

Could be directly declared in the for ()

> +
> +	for (index = 0; index < ARRAY_SIZE(hstt_table); index++)
> +		if (lane_mbps < hstt_table[index].maxfreq)
> +			break;
> +
> +	if (index == ARRAY_SIZE(hstt_table))
> +		index--;
> +
> +	*timing = hstt_table[index].timing;
> +
> +	return 0;
> +}
> +
> +static void dw_mipi_dsi_mchp_power_on(void *priv_data)
> +{
> +	struct dw_mipi_dsi_mchp *dsi = priv_data;
> +
> +	/* Enable the DSI wrapper */
> +	dsi_write(dsi, DSI_PWR_UP, HOST_PWRUP);
> +}
> +
> +static void dw_mipi_dsi_mchp_power_off(void *priv_data)
> +{
> +	struct dw_mipi_dsi_mchp *dsi = priv_data;
> +
> +	/* Disable the DSI wrapper */
> +	dsi_write(dsi, DSI_PWR_UP, HOST_RESET);
> +}
> +
> +struct dw_mipi_dsi_phy_ops dw_mipi_dsi_mchp_phy_ops = {
> +	.init = dw_mipi_dsi_mchp_init,
> +	.power_on = dw_mipi_dsi_mchp_power_on,
> +	.power_off = dw_mipi_dsi_mchp_power_off,
> +	.get_lane_mbps = dw_mipi_dsi_mchp_get_lane_mbps,
> +	.get_timing = dw_mipi_dsi_mchp_get_timing,
> +};
> +
> +static int dw_mipi_dsi_mchp_probe(struct platform_device *pdev)
> +{
> +	struct dw_mipi_dsi_mchp *dsi;
> +	struct resource *res;
> +	struct regmap *sfr;
> +	const struct dw_mipi_dsi_mchp_chip_data *cdata;
> +	int ret;
> +
> +	dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
> +	if (!dsi)
> +		return -ENOMEM;
> +
> +	dsi->dev = &pdev->dev;
> +	cdata = of_device_get_match_data(dsi->dev);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	dsi->base = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(dsi->base)) {
> +		ret = PTR_ERR(dsi->base);
> +		dev_err(dsi->dev, "Unable to get DSI Base address: %d\n", ret);
> +		return ret;
> +	}
> +
> +	dsi->pclk = devm_clk_get(&pdev->dev, "pclk");
> +	if (IS_ERR(dsi->pclk)) {
> +		ret = PTR_ERR(dsi->pclk);
> +		dev_err(dsi->dev, "Unable to get pclk: %d\n", ret);
> +		return ret;
> +	}
> +
> +	dsi->pllref_clk = devm_clk_get(&pdev->dev, "refclk");
> +	if (IS_ERR(dsi->pllref_clk)) {
> +		ret = PTR_ERR(dsi->pllref_clk);
> +		dev_err(dsi->dev, "Unable to get DSI PHY PLL reference clock: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	clk_set_rate(dsi->pllref_clk, DSI_PLL_REF_CLK);
> +	if (clk_get_rate(dsi->pllref_clk) != DSI_PLL_REF_CLK) {
> +		dev_err(dsi->dev, "Failed to set DSI PHY PLL reference clock\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = clk_prepare_enable(dsi->pllref_clk);
> +	if (ret) {
> +		dev_err(dsi->dev, "Failed to enable DSI PHY PLL reference clock: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	sfr = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "microchip,sfr");
> +	if (IS_ERR_OR_NULL(sfr)) {
> +		ret = PTR_ERR(sfr);
> +		dev_err(dsi->dev, "Failed to get handle on Special Function Register: %d\n",
> +			ret);
> +		goto err_dsi_probe;
> +	}
> +	/* Select DSI in SFR's ISS Configuration Register */
> +	ret = regmap_write(sfr, SFR_ISS_CFG, ISS_CFG_DSI_MODE);
> +	if (ret) {
> +		dev_err(dsi->dev, "Failed to enable DSI in SFR ISS configuration register: %d\n",
> +			ret);
> +		goto err_dsi_probe;
> +	}
> +
> +	dsi->pdata.base = dsi->base;
> +	dsi->pdata.max_data_lanes = cdata->max_data_lanes;
> +	dsi->pdata.phy_ops = cdata->phy_ops;
> +	dsi->pdata.priv_data = dsi;
> +	platform_set_drvdata(pdev, dsi);
> +
> +	/* call synopsis probe */
> +	dsi->dsi = dw_mipi_dsi_probe(pdev, &dsi->pdata);
> +	if (IS_ERR(dsi->dsi)) {
> +		ret = PTR_ERR(dsi->dsi);
> +		dev_err(dsi->dev, "Failed to initialize mipi dsi host: %d\n", ret);
> +		goto err_dsi_probe;
> +	}
> +
> +	return 0;
> +
> +err_dsi_probe:
> +	clk_disable_unprepare(dsi->pllref_clk);
> +
> +	return ret;
> +}
> +
> +static int dw_mipi_dsi_mchp_remove(struct platform_device *pdev)
> +{
> +	struct dw_mipi_dsi_mchp *dsi = platform_get_drvdata(pdev);
> +
> +	dw_mipi_dsi_remove(dsi->dsi);
> +	clk_disable_unprepare(dsi->pllref_clk);
> +
> +	return 0;
> +}
> +
> +static const struct dw_mipi_dsi_mchp_chip_data sam9x75_chip_data = {
> +	.max_data_lanes = 4,
> +	.phy_ops = &dw_mipi_dsi_mchp_phy_ops,
> +};
> +
> +static const struct of_device_id dw_mipi_dsi_mchp_dt_ids[] = {
> +	{
> +	 .compatible	= "microchip,sam9x75-mipi-dsi",
> +	 .data		= &sam9x75_chip_data,
> +	},
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, dw_mipi_dsi_mchp_dt_ids);
> +
> +struct platform_driver dw_mipi_dsi_mchp_driver = {
> +	.probe		= dw_mipi_dsi_mchp_probe,
> +	.remove		= dw_mipi_dsi_mchp_remove,
> +	.driver		= {
> +		.of_match_table = dw_mipi_dsi_mchp_dt_ids,
> +		.name		= "dw-mipi-dsi-mchp",
> +	},
> +};
> +module_platform_driver(dw_mipi_dsi_mchp_driver);
> +
> +MODULE_AUTHOR("Manikandan Muralidharan <manikandan.m@microchip.com>");
> +MODULE_DESCRIPTION("Microchip DW MIPI DSI controller wrapper driver");
> +MODULE_LICENSE("GPL");