[PATCH v3 0/4] MIPI DSI Controller support for SAM9X75 series

[PATCH v3 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.

Changelogs are available in respective patches.

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    | 116 ++++
 MAINTAINERS                                   |   7 +
 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, 677 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 v3 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>
---
changes in v3:
- Describe the clocks used

changes in v2:
- List the clocks with description
- remove describing 'remove-endpoint' properties
- remove unused label, node and fix example DT indentation
- cosmetic fixes
---
 .../bridge/microchip,sam9x75-mipi-dsi.yaml    | 116 ++++++++++++++++++
 1 file changed, 116 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..3c86f0cd49e9
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
@@ -0,0 +1,116 @@
+# 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:
+    items:
+      - description:
+          Peripheral Bus Clock between LCDC and MIPI DPHY
+      - description:
+          MIPI DPHY Interface reference clock for PLL block
+
+  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
+
+      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
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - ports
+
+unevaluatedProperties: false
+
+examples:
+  - |
+     #include <dt-bindings/clock/at91.h>
+     #include <dt-bindings/gpio/gpio.h>
+
+     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>;
+           };
+         };
+       };
+     };
+...
-- 
2.25.1

[PATCH v3 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>
---
changes in v3:
- make remove callback return void

changes in v2:
- use static const with global variables
- replace dev_err with dev_err_probe
- move clk_prepare_enable to simplify the error path
- use FIELD_PREP calls
- remove unused macros and unused functions
- rename function name with mchp_ suffix
- add suspend and resume pm calls to handle pllref_clk
---
 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..5f9afdcb72d2
--- /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/bitfield.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.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.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_UNTESTCLR			0
+
+#define DSI_PHY_TST_CTRL1		0xb8
+#define PHY_TESTEN			BIT(16)
+#define PHY_UNTESTEN			0
+#define PHY_TESTDOUT_MASK		GENMASK(15, 8)
+#define PHY_TESTDIN_MASK		GENMASK(7, 0)
+
+#define BYPASS_VCO_RANGE		BIT(7)
+#define VCO_RANGE_CON_SEL_MASK		GENMASK(5, 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_MASK		GENMASK(3, 0)
+#define CP_PROGRAM_EN			BIT(7)
+
+#define LPF_RESISTORS_15_6KOHM		0x1
+#define LPF_RESISTORS_14_4KOHM		0x4
+#define LPF_RESISTORS_12_8KOHM		0x8
+#define LPF_RESISTORS_11_4KOHM		0x10
+#define LPF_PROGRAM_EN			BIT(6)
+#define LPF_RESISTORS_SEL_MASK		GENMASK(5, 0)
+
+#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 {
+	const struct dw_mipi_dsi_phy_ops *phy_ops;
+	unsigned int max_data_lanes;
+};
+
+struct dw_mipi_dsi_mchp {
+	struct device *dev;
+	void __iomem *base;
+	struct dw_mipi_dsi *dsi;
+	struct clk *pllref_clk;
+	struct dw_mipi_dsi_plat_data pdata;
+
+	/* For PLL config */
+	unsigned int lane_mbps;
+	u16 input_div;
+	u16 feedback_div;
+	u32 format;
+};
+
+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,	\
+	}				\
+}
+
+static const 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 mchp_max_mbps_to_parameter(unsigned int max_mbps)
+{
+	for (int index = 0; index < ARRAY_SIZE(dppa_map); index++)
+		if (dppa_map[index].max_mbps >= max_mbps)
+			return index;
+
+	return -EINVAL;
+}
+
+static inline void mchp_phy_write(struct dw_mipi_dsi_mchp *dsi, u32 reg, u32 val)
+{
+	writel(val, dsi->base + reg);
+}
+
+static void dw_mipi_dsi_mchp_phy_write(struct dw_mipi_dsi_mchp *dsi,
+				       u8 test_code,
+				       u8 test_data)
+{
+	/* General DPHY control operation */
+
+	mchp_phy_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLK | PHY_UNTESTCLR);
+	mchp_phy_write(dsi, DSI_PHY_TST_CTRL1, PHY_TESTEN |
+		       FIELD_PREP(PHY_TESTDOUT_MASK, 1) |
+		       FIELD_PREP(PHY_TESTDIN_MASK, test_code));
+	mchp_phy_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLK | PHY_UNTESTCLR);
+	mchp_phy_write(dsi, DSI_PHY_TST_CTRL1, PHY_UNTESTEN |
+		       FIELD_PREP(PHY_TESTDOUT_MASK, 0) |
+		       FIELD_PREP(PHY_TESTDIN_MASK, test_data));
+	mchp_phy_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLK | PHY_UNTESTCLR);
+	mchp_phy_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 = mchp_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 */
+	mchp_phy_write(dsi, DSI_PHY_RSTZ, PHY_SHUTDOWNZ);
+
+	dw_mipi_dsi_mchp_phy_write(dsi, PLL_BIAS_CUR_SEL_CAP_VCO_CONTROL,
+				   BYPASS_VCO_RANGE |
+				   FIELD_PREP(VCO_RANGE_CON_SEL_MASK, vco) |
+				   VCO_IN_CAP_CON_LOW);
+
+	dw_mipi_dsi_mchp_phy_write(dsi, PLL_CP_CONTROL_PLL_LOCK_BYPASS,
+				   FIELD_PREP(CP_CURRENT_SEL_MASK, dppa_map[index].icpctrl));
+
+	dw_mipi_dsi_mchp_phy_write(dsi, PLL_LPF_AND_CP_CONTROL,
+				   CP_PROGRAM_EN | LPF_PROGRAM_EN |
+				   FIELD_PREP(LPF_RESISTORS_SEL_MASK, dppa_map[index].lpfctrl));
+
+	dw_mipi_dsi_mchp_phy_write(dsi, PLL_INPUT_AND_LOOP_DIVIDER_RATIOS_CONTROL,
+				   PLL_LOOP_DIV_EN | PLL_INPUT_DIV_EN);
+
+	dw_mipi_dsi_mchp_phy_write(dsi, PLL_INPUT_DIVIDER_RATIO,
+				   INPUT_DIVIDER(dsi->input_div));
+
+	dw_mipi_dsi_mchp_phy_write(dsi, PLL_LOOP_DIVIDER_RATIO,
+				   LOOP_DIV_LOW_SEL(dsi->feedback_div) |
+				   LOW_PROGRAM_EN);
+
+	dw_mipi_dsi_mchp_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;
+
+	for (best_freq = 0, _prediv = min_prediv; _prediv <= max_prediv; _prediv++) {
+		/* Fvco = Fref * M / N */
+		freq_factor = 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 = _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 = 0;
+
+	for (; 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 */
+	mchp_phy_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 */
+	mchp_phy_write(dsi, DSI_PWR_UP, HOST_RESET);
+}
+
+static int dw_mipi_dsi_mchp_probe(struct platform_device *pdev)
+{
+	struct dw_mipi_dsi_mchp *dsi;
+	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);
+
+	dsi->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(dsi->base)) {
+		ret = PTR_ERR(dsi->base);
+		dev_err_probe(dsi->dev, ret, "Unable to get DSI Base address\n");
+		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_probe(dsi->dev, ret, "Unable to get DSI PHY PLL reference clock\n");
+		return ret;
+	}
+
+	sfr = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "microchip,sfr");
+	if (IS_ERR(sfr)) {
+		ret = PTR_ERR(sfr);
+		dev_err_probe(dsi->dev, ret, "Failed to get handle on Special Function Register\n");
+		return ret;
+	}
+	/* Select DSI in SFR's ISS Configuration Register */
+	ret = regmap_write(sfr, SFR_ISS_CFG, ISS_CFG_DSI_MODE);
+	if (ret) {
+		dev_err_probe(dsi->dev, ret, "Failed to enable DSI in SFR_ISS_CFG Register\n");
+		return ret;
+	}
+
+	clk_set_rate(dsi->pllref_clk, DSI_PLL_REF_CLK);
+	if (clk_get_rate(dsi->pllref_clk) != DSI_PLL_REF_CLK) {
+		ret = -EINVAL;
+		dev_err_probe(dsi->dev, ret, "Failed to set DSI PHY PLL reference clock\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(dsi->pllref_clk);
+	if (ret) {
+		dev_err_probe(dsi->dev, ret, "Failed to enable DSI PHY PLL reference clock\n");
+		return ret;
+	}
+
+	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_probe(dsi->dev, ret, "Failed to initialize mipi dsi host\n");
+		clk_disable_unprepare(dsi->pllref_clk);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void 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);
+}
+
+static int dw_mipi_dsi_mchp_suspend(struct device *dev)
+{
+	struct dw_mipi_dsi_mchp *dsi = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(dsi->pllref_clk);
+
+	return 0;
+}
+
+static int dw_mipi_dsi_mchp_resume(struct device *dev)
+{
+	struct dw_mipi_dsi_mchp *dsi = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(dsi->pllref_clk);
+	if (ret) {
+		dev_err(dsi->dev, "Failed to enable pllref_clk: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct dev_pm_ops dw_mipi_dsi_mchp_pm_ops = {
+	SYSTEM_SLEEP_PM_OPS(dw_mipi_dsi_mchp_suspend,
+			    dw_mipi_dsi_mchp_resume)
+	RUNTIME_PM_OPS(dw_mipi_dsi_mchp_suspend,
+		       dw_mipi_dsi_mchp_resume, NULL)
+};
+
+static const 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 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",
+		.pm		= &dw_mipi_dsi_mchp_pm_ops,
+	},
+};
+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 v3 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>
---
changes in v3:
- Drop T: section
---
 MAINTAINERS | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index a1537a149e9a..270cbe5f0c6a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15086,6 +15086,13 @@ 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
+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 v3 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 6eabe2313c9a..beb29c4832ce 100644
--- a/arch/arm/configs/at91_dt_defconfig
+++ b/arch/arm/configs/at91_dt_defconfig
@@ -144,6 +144,7 @@ CONFIG_VIDEO_OV7740=m
 CONFIG_DRM=y
 CONFIG_DRM_ATMEL_HLCDC=y
 CONFIG_DRM_MICROCHIP_LVDS_SERIALIZER=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 v3 1/4] dt-bindings: display: bridge: add sam9x75-mipi-dsi binding

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 2793 bytes --]

On Wed, Aug 14, 2024 at 04:22:53PM +0530, 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>
> ---
> changes in v3:
> - Describe the clocks used
> 
> changes in v2:
> - List the clocks with description
> - remove describing 'remove-endpoint' properties
> - remove unused label, node and fix example DT indentation
> - cosmetic fixes
> ---
>  .../bridge/microchip,sam9x75-mipi-dsi.yaml    | 116 ++++++++++++++++++
>  1 file changed, 116 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..3c86f0cd49e9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
> @@ -0,0 +1,116 @@
> +# 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:
> +    items:
> +      - description:
> +          Peripheral Bus Clock between LCDC and MIPI DPHY
> +      - description:
> +          MIPI DPHY Interface reference clock for PLL block
> +
> +  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.

I'm curious - why is this phandle required? How many SFR nodes are there
on the platform?

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

Re: [PATCH v3 2/4] drm/bridge: add Microchip DSI controller support for sam9x7 SoC series

[kernel test robot]

Hi Manikandan,

kernel test robot noticed the following build warnings:

[auto build test WARNING on robh/for-next]
[also build test WARNING on drm-misc/drm-misc-next linus/master v6.11-rc3 next-20240816]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Manikandan-Muralidharan/dt-bindings-display-bridge-add-sam9x75-mipi-dsi-binding/20240814-234923
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
patch link:    https://lore.kernel.org/r/20240814105256.177319-3-manikandan.m%40microchip.com
patch subject: [PATCH v3 2/4] drm/bridge: add Microchip DSI controller support for sam9x7 SoC series
config: arm-randconfig-r071-20240816 (https://download.01.org/0day-ci/archive/20240816/202408162158.TlOqyoUA-lkp@intel.com/config)
compiler: clang version 15.0.7 (https://github.com/llvm/llvm-project 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202408162158.TlOqyoUA-lkp@intel.com/

smatch warnings:
drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c:293 dw_mipi_dsi_mchp_get_lane_mbps() warn: unsigned 'bpp' is never less than zero.
drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c:293 dw_mipi_dsi_mchp_get_lane_mbps() warn: error code type promoted to positive: 'bpp'
drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c:314 dw_mipi_dsi_mchp_get_lane_mbps() error: uninitialized symbol 'target_mbps'.

vim +/bpp +293 drivers/gpu/drm/bridge/dw-mipi-dsi-mchp.c

   276	
   277	static int dw_mipi_dsi_mchp_get_lane_mbps(void *priv_data,
   278						  const struct drm_display_mode *mode,
   279						  unsigned long mode_flags, u32 lanes,
   280						  u32 format, unsigned int *lane_mbps)
   281	{
   282		struct dw_mipi_dsi_mchp *dsi = priv_data;
   283		unsigned long best_freq, fvco_min, fvco_max, fin, fout;
   284		unsigned long min_delta = ULONG_MAX, delta;
   285		unsigned int mpclk, target_mbps, desired_mbps;
   286		unsigned int max_mbps = dppa_map[ARRAY_SIZE(dppa_map) - 1].max_mbps;
   287		unsigned int bpp, min_prediv, max_prediv;
   288		unsigned int _fbdiv, best_fbdiv, _prediv, best_prediv;
   289		u64 freq_factor;
   290	
   291		dsi->format = format;
   292		bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
 > 293		if (bpp < 0) {
   294			dev_err(dsi->dev,
   295				"failed to get bpp for pixel format %d\n",
   296				dsi->format);
   297			return bpp;
   298		}
   299	
   300		mpclk = DIV_ROUND_UP(mode->clock, MSEC_PER_SEC);
   301		if (mpclk) {
   302			/* take 1/0.8, since mbps must be bigger than bandwidth of RGB */
   303			desired_mbps = mpclk * (bpp / lanes) * 10 / 8;
   304			if (desired_mbps < max_mbps) {
   305				target_mbps = desired_mbps;
   306			} else {
   307				dev_err(dsi->dev,
   308					"DPHY clock frequency is out of range\n");
   309				return -ERANGE;
   310			}
   311		}
   312	
   313		fin = clk_get_rate(dsi->pllref_clk);
 > 314		fout = target_mbps * USEC_PER_SEC;
   315	
   316		/* constraint: 5Mhz <= Fref / N <= 40MHz */
   317		min_prediv = DIV_ROUND_UP(fin, 40 * USEC_PER_SEC);
   318		max_prediv = fin / (5 * USEC_PER_SEC);
   319	
   320		/* constraint: 80MHz <= Fvco <= 1000Mhz */
   321		fvco_min = 80 * USEC_PER_SEC;
   322		fvco_max = 1000 * USEC_PER_SEC;
   323	
   324		for (best_freq = 0, _prediv = min_prediv; _prediv <= max_prediv; _prediv++) {
   325			/* Fvco = Fref * M / N */
   326			freq_factor = fout * _prediv;
   327			do_div(freq_factor, fin);
   328			_fbdiv = freq_factor;
   329			/*
   330			 * Due to the use of a "by 2 pre-scaler," the range of the
   331			 * feedback multiplication value M is limited to even division
   332			 * numbers, and m must be greater than 6, not bigger than 512.
   333			 */
   334			if (_fbdiv < 6 || _fbdiv > 512)
   335				continue;
   336	
   337			_fbdiv += _fbdiv % 2;
   338	
   339			freq_factor = _fbdiv * fin;
   340			do_div(freq_factor, _prediv);
   341			if (freq_factor < fvco_min || freq_factor > fvco_max)
   342				continue;
   343	
   344			delta = abs(fout - freq_factor);
   345			if (delta < min_delta) {
   346				best_prediv = _prediv;
   347				best_fbdiv = _fbdiv;
   348				min_delta = delta;
   349				best_freq = freq_factor;
   350			}
   351		}
   352	
   353		if (best_freq) {
   354			dsi->lane_mbps = DIV_ROUND_UP(best_freq, USEC_PER_SEC);
   355			*lane_mbps = dsi->lane_mbps;
   356			dsi->input_div = best_prediv;
   357			dsi->feedback_div = best_fbdiv;
   358		} else {
   359			dev_err(dsi->dev, "Can not find best_freq for DPHY\n");
   360			return -EINVAL;
   361		}
   362	
   363		return 0;
   364	}
   365	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v3 1/4] dt-bindings: display: bridge: add sam9x75-mipi-dsi binding

[Manikandan.M]

Hi Conor,

On 14/08/24 7:29 pm, Conor Dooley wrote:
> On Wed, Aug 14, 2024 at 04:22:53PM +0530, 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>
>> ---
>> changes in v3:
>> - Describe the clocks used
>>
>> changes in v2:
>> - List the clocks with description
>> - remove describing 'remove-endpoint' properties
>> - remove unused label, node and fix example DT indentation
>> - cosmetic fixes
>> ---
>>   .../bridge/microchip,sam9x75-mipi-dsi.yaml    | 116 ++++++++++++++++++
>>   1 file changed, 116 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..3c86f0cd49e9
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
>> @@ -0,0 +1,116 @@
>> +# 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:
>> +    items:
>> +      - description:
>> +          Peripheral Bus Clock between LCDC and MIPI DPHY
>> +      - description:
>> +          MIPI DPHY Interface reference clock for PLL block
>> +
>> +  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.
> I'm curious - why is this phandle required? How many SFR nodes are there
> on the platform?
This phandle is to map the memory region of SFR node and configure the 
DSI bit in the SFR's ISS configuration register.
currently there is only one SFR node in this platform.

-- 
Thanks and Regards,
Manikandan M.

Re: [PATCH v3 1/4] dt-bindings: display: bridge: add sam9x75-mipi-dsi binding

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 3486 bytes --]

On Tue, Sep 17, 2024 at 03:16:53AM +0000, Manikandan.M@microchip.com wrote:
> Hi Conor,
> 
> On 14/08/24 7:29 pm, Conor Dooley wrote:
> > On Wed, Aug 14, 2024 at 04:22:53PM +0530, 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>
> >> ---
> >> changes in v3:
> >> - Describe the clocks used
> >>
> >> changes in v2:
> >> - List the clocks with description
> >> - remove describing 'remove-endpoint' properties
> >> - remove unused label, node and fix example DT indentation
> >> - cosmetic fixes
> >> ---
> >>   .../bridge/microchip,sam9x75-mipi-dsi.yaml    | 116 ++++++++++++++++++
> >>   1 file changed, 116 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..3c86f0cd49e9
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
> >> @@ -0,0 +1,116 @@
> >> +# 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:
> >> +    items:
> >> +      - description:
> >> +          Peripheral Bus Clock between LCDC and MIPI DPHY
> >> +      - description:
> >> +          MIPI DPHY Interface reference clock for PLL block
> >> +
> >> +  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.
> > I'm curious - why is this phandle required? How many SFR nodes are there
> > on the platform?
> This phandle is to map the memory region of SFR node and configure the 
> DSI bit in the SFR's ISS configuration register.
> currently there is only one SFR node in this platform.

What does "currently" mean? The platform either has one or it does not,
currently makes it sound like it has more than one but the dts only has
one.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

Re: [PATCH v3 1/4] dt-bindings: display: bridge: add sam9x75-mipi-dsi binding

[Manikandan.M]

On 17/09/24 6:08 pm, Conor Dooley wrote:
> On Tue, Sep 17, 2024 at 03:16:53AM +0000,Manikandan.M@microchip.com  wrote:
>> Hi Conor,
>>
>> On 14/08/24 7:29 pm, Conor Dooley wrote:
>>> On Wed, Aug 14, 2024 at 04:22:53PM +0530, 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>
>>>> ---
>>>> changes in v3:
>>>> - Describe the clocks used
>>>>
>>>> changes in v2:
>>>> - List the clocks with description
>>>> - remove describing 'remove-endpoint' properties
>>>> - remove unused label, node and fix example DT indentation
>>>> - cosmetic fixes
>>>> ---
>>>>    .../bridge/microchip,sam9x75-mipi-dsi.yaml    | 116 ++++++++++++++++++
>>>>    1 file changed, 116 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..3c86f0cd49e9
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x75-mipi-dsi.yaml
>>>> @@ -0,0 +1,116 @@
>>>> +# 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:
>>>> +    items:
>>>> +      - description:
>>>> +          Peripheral Bus Clock between LCDC and MIPI DPHY
>>>> +      - description:
>>>> +          MIPI DPHY Interface reference clock for PLL block
>>>> +
>>>> +  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.
>>> I'm curious - why is this phandle required? How many SFR nodes are there
>>> on the platform?
>> This phandle is to map the memory region of SFR node and configure the
>> DSI bit in the SFR's ISS configuration register.
>> currently there is only one SFR node in this platform.
> What does "currently" mean? The platform either has one or it does not,
> currently makes it sound like it has more than one but the dts only has
> one.
Apologies, I would like to clarify the statement that this platform only 
has one 32-bit special function register implemented.
-- 
Thanks and Regards,
Manikandan M.

Re: [PATCH v3 1/4] dt-bindings: display: bridge: add sam9x75-mipi-dsi binding

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 1301 bytes --]

On Wed, Sep 18, 2024 at 03:00:45AM +0000, Manikandan.M@microchip.com wrote:
> On 17/09/24 6:08 pm, Conor Dooley wrote:
> > On Tue, Sep 17, 2024 at 03:16:53AM +0000,Manikandan.M@microchip.com  wrote:
> >> Hi Conor,
> >>
> >> On 14/08/24 7:29 pm, Conor Dooley wrote:
> >>> On Wed, Aug 14, 2024 at 04:22:53PM +0530, Manikandan Muralidharan wrote:

> >>>> +  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.
> >>> I'm curious - why is this phandle required? How many SFR nodes are there
> >>> on the platform?
> >> This phandle is to map the memory region of SFR node and configure the
> >> DSI bit in the SFR's ISS configuration register.
> >> currently there is only one SFR node in this platform.
> > What does "currently" mean? The platform either has one or it does not,
> > currently makes it sound like it has more than one but the dts only has
> > one.
> Apologies, I would like to clarify the statement that this platform only 
> has one 32-bit special function register implemented.

In that case, you dont need a phandle at all, just look the sfr up by
its compatible.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]