firmware: zynqmp: Add MMIO read and write support for PS_MODE pin

Add Xilinx ZynqMP firmware MMIO APIs support to set and get PS_MODE
pins value and status. These APIs create an interface path between
mode pin controller driver and low-level API to access GPIO pins.
Signed-off-by: Piyush Mehta <piyush.mehta@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

drivers/firmware/xilinx/zynqmp.c

@@ -28,6 +28,13 @@
 /* Max HashMap Order for PM API feature check (1<<7 = 128) */
 #define PM_API_FEATURE_CHECK_MAX_ORDER  7
 
+/* CRL registers and bitfields */
+#define CRL_APB_BASE			0xFF5E0000U
+/* BOOT_PIN_CTRL- Used to control the mode pins after boot */
+#define CRL_APB_BOOT_PIN_CTRL		(CRL_APB_BASE + (0x250U))
+/* BOOT_PIN_CTRL_MASK- out_val[11:8], out_en[3:0] */
+#define CRL_APB_BOOTPIN_CTRL_MASK	0xF0FU
+
 static bool feature_check_enabled;
 static DEFINE_HASHTABLE(pm_api_features_map, PM_API_FEATURE_CHECK_MAX_ORDER);
 
@@ -925,6 +932,45 @@ int zynqmp_pm_pinctrl_set_config(const u32 pin, const u32 param,
 }
 EXPORT_SYMBOL_GPL(zynqmp_pm_pinctrl_set_config);
 
+/**
+ * zynqmp_pm_bootmode_read() - PM Config API for read bootpin status
+ * @ps_mode: Returned output value of ps_mode
+ *
+ * This API function is to be used for notify the power management controller
+ * to read bootpin status.
+ *
+ * Return: status, either success or error+reason
+ */
+unsigned int zynqmp_pm_bootmode_read(u32 *ps_mode)
+{
+	unsigned int ret;
+	u32 ret_payload[PAYLOAD_ARG_CNT];
+
+	ret = zynqmp_pm_invoke_fn(PM_MMIO_READ, CRL_APB_BOOT_PIN_CTRL, 0,
+				  0, 0, ret_payload);
+
+	*ps_mode = ret_payload[1];
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(zynqmp_pm_bootmode_read);
+
+/**
+ * zynqmp_pm_bootmode_write() - PM Config API for Configure bootpin
+ * @ps_mode: Value to be written to the bootpin ctrl register
+ *
+ * This API function is to be used for notify the power management controller
+ * to configure bootpin.
+ *
+ * Return: Returns status, either success or error+reason
+ */
+int zynqmp_pm_bootmode_write(u32 ps_mode)
+{
+	return zynqmp_pm_invoke_fn(PM_MMIO_WRITE, CRL_APB_BOOT_PIN_CTRL,
+				   CRL_APB_BOOTPIN_CTRL_MASK, ps_mode, 0, NULL);
+}
+EXPORT_SYMBOL_GPL(zynqmp_pm_bootmode_write);
+
 /**
  * zynqmp_pm_init_finalize() - PM call to inform firmware that the caller
  *			       master has initialized its own power management

include/linux/firmware/xlnx-zynqmp.h

@@ -72,6 +72,8 @@ enum pm_api_id {
 	PM_SET_REQUIREMENT = 15,
 	PM_RESET_ASSERT = 17,
 	PM_RESET_GET_STATUS = 18,
+	PM_MMIO_WRITE = 19,
+	PM_MMIO_READ = 20,
 	PM_PM_INIT_FINALIZE = 21,
 	PM_FPGA_LOAD = 22,
 	PM_FPGA_GET_STATUS = 23,
@@ -390,6 +392,8 @@ int zynqmp_pm_sd_dll_reset(u32 node_id, u32 type);
 int zynqmp_pm_reset_assert(const enum zynqmp_pm_reset reset,
 			   const enum zynqmp_pm_reset_action assert_flag);
 int zynqmp_pm_reset_get_status(const enum zynqmp_pm_reset reset, u32 *status);
+unsigned int zynqmp_pm_bootmode_read(u32 *ps_mode);
+int zynqmp_pm_bootmode_write(u32 ps_mode);
 int zynqmp_pm_init_finalize(void);
 int zynqmp_pm_set_suspend_mode(u32 mode);
 int zynqmp_pm_request_node(const u32 node, const u32 capabilities,
@@ -520,6 +524,16 @@ static inline int zynqmp_pm_reset_get_status(const enum zynqmp_pm_reset reset,
 	return -ENODEV;
 }
 
+static inline unsigned int zynqmp_pm_bootmode_read(u32 *ps_mode)
+{
+	return -ENODEV;
+}
+
+static inline int zynqmp_pm_bootmode_write(u32 ps_mode)
+{
+	return -ENODEV;
+}
+
 static inline int zynqmp_pm_init_finalize(void)
 {
 	return -ENODEV;