[PATCH 12/17] soc: ti: pruss: add pruss_cfg_read()/update() API

[Roger Quadros <rogerq@ti.com>]

Add two new APIs pruss_cfg_read() and pruss_cfg_update()
to the PRUSS platform driver to allow other drivers to read and
update the registers in the CFG submodule within the PRUSS.

This interface provides a simple way for client drivers
without having them to include and parse these syscon nodes within
their respective device nodes.

The register definitions for the CFG registors have also been added.

Signed-off-by: Roger Quadros <rogerq@ti.com>
---
 drivers/soc/ti/Kconfig |   1 +
 drivers/soc/ti/pruss.c |  52 +++++++++++++++++++++++++
 drivers/soc/ti/pruss.h |   2 +
 include/linux/pruss.h  | 101 +++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 156 insertions(+)

diff --git a/drivers/soc/ti/Kconfig b/drivers/soc/ti/Kconfig
index d1ea6da..d239996 100644
--- a/drivers/soc/ti/Kconfig
+++ b/drivers/soc/ti/Kconfig
@@ -76,6 +76,7 @@ config TI_SCI_PM_DOMAINS
 config TI_PRUSS
 	tristate "TI PRU-ICSS Subsystem Platform drivers"
 	depends on SOC_AM33XX
+	select MFD_SYSCON
 	default n
 	help
 	  TI PRU-ICSS Subsystem platform specific support.
diff --git a/drivers/soc/ti/pruss.c b/drivers/soc/ti/pruss.c
index 90ee5b9..63c7d8c 100644
--- a/drivers/soc/ti/pruss.c
+++ b/drivers/soc/ti/pruss.c
@@ -10,9 +10,11 @@
 #include <linux/dma-mapping.h>
 #include <linux/module.h>
 #include <linux/io.h>
+#include <linux/mfd/syscon.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>
 #include <linux/pruss.h>
+#include <linux/regmap.h>
 #include <linux/remoteproc.h>
 
 #include "pruss.h"
@@ -152,6 +154,47 @@ int pruss_release_mem_region(struct pruss *pruss,
 }
 EXPORT_SYMBOL_GPL(pruss_release_mem_region);
 
+/**
+ * pruss_cfg_read() - read a PRUSS CFG register
+ * @pruss: the pruss instance handle
+ * @reg: register offset within the CFG sub-module
+ * @val: pointer to return the value in
+ *
+ * Reads a given register within CFG module of PRUSS
+ * and returns it through the passed-in @val pointer
+ *
+ * Returns 0 on success, or an error code otherwise
+ */
+int pruss_cfg_read(struct pruss *pruss, unsigned int reg, unsigned int *val)
+{
+	if (IS_ERR_OR_NULL(pruss))
+		return -EINVAL;
+
+	return regmap_read(pruss->cfg, reg, val);
+}
+EXPORT_SYMBOL_GPL(pruss_cfg_read);
+
+/**
+ * pruss_cfg_update() - update a PRUSS CFG register
+ * @pruss: the pruss instance handle
+ * @reg: register offset within the CFG sub-module
+ * @mask: bit mask to use for programming the @val
+ * @val: value to write
+ *
+ * Updates a given register within CFG sub-module of PRUSS
+ *
+ * Returns 0 on success, or an error code otherwise
+ */
+int pruss_cfg_update(struct pruss *pruss, unsigned int reg,
+		     unsigned int mask, unsigned int val)
+{
+	if (IS_ERR_OR_NULL(pruss))
+		return -EINVAL;
+
+	return regmap_update_bits(pruss->cfg, reg, mask, val);
+}
+EXPORT_SYMBOL_GPL(pruss_cfg_update);
+
 static int pruss_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -180,6 +223,15 @@ static int pruss_probe(struct platform_device *pdev)
 	pruss->dev = dev;
 	mutex_init(&pruss->lock);
 
+	np = of_get_child_by_name(node, "cfg");
+	if (!np)
+		return -ENODEV;
+
+	pruss->cfg = syscon_node_to_regmap(np);
+	of_node_put(np);
+	if (IS_ERR(pruss->cfg))
+		return -ENODEV;
+
 	np = of_get_child_by_name(node, "memories");
 	if (!np)
 		return -ENODEV;
diff --git a/drivers/soc/ti/pruss.h b/drivers/soc/ti/pruss.h
index f8878c2..45de1be 100644
--- a/drivers/soc/ti/pruss.h
+++ b/drivers/soc/ti/pruss.h
@@ -34,6 +34,7 @@ struct pruss_intc_config {
 /**
  * struct pruss - PRUSS parent structure
  * @dev: pruss device pointer
+ * @cfg: regmap for config region
  * @mem_regions: data for each of the PRUSS memory regions
  * @mem_in_use: to indicate if memory resource is in use
  * @host_mask: indicate which HOST IRQs are enabled
@@ -41,6 +42,7 @@ struct pruss_intc_config {
  */
 struct pruss {
 	struct device *dev;
+	struct regmap *cfg;
 	struct pruss_mem_region mem_regions[PRUSS_MEM_MAX];
 	struct pruss_mem_region *mem_in_use[PRUSS_MEM_MAX];
 	u32 host_mask;
diff --git a/include/linux/pruss.h b/include/linux/pruss.h
index b9135d6..3ed175a 100644
--- a/include/linux/pruss.h
+++ b/include/linux/pruss.h
@@ -10,6 +10,92 @@
 #ifndef __LINUX_PRUSS_H
 #define __LINUX_PRUSS_H
 
+/*
+ * PRU_ICSS_CFG registers
+ * SYSCFG, ISRP, ISP, IESP, IECP, SCRP applicable on AMxxxx devices only
+ */
+#define PRUSS_CFG_REVID		0x00
+#define PRUSS_CFG_SYSCFG	0x04
+#define PRUSS_CFG_GPCFG(x)	(0x08 + (x) * 4)
+#define PRUSS_CFG_CGR		0x10
+#define PRUSS_CFG_ISRP		0x14
+#define PRUSS_CFG_ISP		0x18
+#define PRUSS_CFG_IESP		0x1C
+#define PRUSS_CFG_IECP		0x20
+#define PRUSS_CFG_SCRP		0x24
+#define PRUSS_CFG_PMAO		0x28
+#define PRUSS_CFG_MII_RT	0x2C
+#define PRUSS_CFG_IEPCLK	0x30
+#define PRUSS_CFG_SPP		0x34
+#define PRUSS_CFG_PIN_MX	0x40
+
+/* PRUSS_GPCFG register bits */
+#define PRUSS_GPCFG_PRU_GPO_SH_SEL		BIT(25)
+
+#define PRUSS_GPCFG_PRU_DIV1_SHIFT		20
+#define PRUSS_GPCFG_PRU_DIV1_MASK		GENMASK(24, 20)
+
+#define PRUSS_GPCFG_PRU_DIV0_SHIFT		15
+#define PRUSS_GPCFG_PRU_DIV0_MASK		GENMASK(15, 19)
+
+#define PRUSS_GPCFG_PRU_GPO_MODE		BIT(14)
+#define PRUSS_GPCFG_PRU_GPO_MODE_DIRECT		0
+#define PRUSS_GPCFG_PRU_GPO_MODE_SERIAL		BIT(14)
+
+#define PRUSS_GPCFG_PRU_GPI_SB			BIT(13)
+
+#define PRUSS_GPCFG_PRU_GPI_DIV1_SHIFT		8
+#define PRUSS_GPCFG_PRU_GPI_DIV1_MASK		GENMASK(12, 8)
+
+#define PRUSS_GPCFG_PRU_GPI_DIV0_SHIFT		3
+#define PRUSS_GPCFG_PRU_GPI_DIV0_MASK		GENMASK(7, 3)
+
+#define PRUSS_GPCFG_PRU_GPI_CLK_MODE_POSITIVE	0
+#define PRUSS_GPCFG_PRU_GPI_CLK_MODE_NEGATIVE	BIT(2)
+#define PRUSS_GPCFG_PRU_GPI_CLK_MODE		BIT(2)
+
+#define PRUSS_GPCFG_PRU_GPI_MODE_MASK		GENMASK(1, 0)
+#define PRUSS_GPCFG_PRU_GPI_MODE_SHIFT		0
+
+#define PRUSS_GPCFG_PRU_MUX_SEL_SHIFT		26
+#define PRUSS_GPCFG_PRU_MUX_SEL_MASK		GENMASK(29, 26)
+
+/* PRUSS_MII_RT register bits */
+#define PRUSS_MII_RT_EVENT_EN			BIT(0)
+
+/* PRUSS_SPP register bits */
+#define PRUSS_SPP_XFER_SHIFT_EN			BIT(1)
+#define PRUSS_SPP_PRU1_PAD_HP_EN		BIT(0)
+
+/**
+ * enum pruss_gp_mux_sel - PRUSS GPI/O Mux modes for the
+ * PRUSS_GPCFG0/1 registers
+ *
+ * NOTE: The below defines are the most common values, but there
+ * are some exceptions like on 66AK2G, where the RESERVED and MII2
+ * values are interchanged. Also, this bit-field does not exist on
+ * AM335x SoCs
+ */
+enum pruss_gp_mux_sel {
+	PRUSS_GP_MUX_SEL_GP = 0,
+	PRUSS_GP_MUX_SEL_ENDAT,
+	PRUSS_GP_MUX_SEL_RESERVED,
+	PRUSS_GP_MUX_SEL_SD,
+	PRUSS_GP_MUX_SEL_MII2,
+	PRUSS_GP_MUX_SEL_MAX,
+};
+
+/**
+ * enum pruss_gpi_mode - PRUSS GPI configuration modes, used
+ *			 to program the PRUSS_GPCFG0/1 registers
+ */
+enum pruss_gpi_mode {
+	PRUSS_GPI_MODE_DIRECT = 0,
+	PRUSS_GPI_MODE_PARALLEL,
+	PRUSS_GPI_MODE_28BIT_SHIFT,
+	PRUSS_GPI_MODE_MII,
+};
+
 /**
  * enum pruss_mem - PRUSS memory range identifiers
  */
@@ -46,6 +132,10 @@ int pruss_release_mem_region(struct pruss *pruss,
 
 int pruss_intc_trigger(unsigned int irq);
 
+int pruss_cfg_read(struct pruss *pruss, unsigned int reg, unsigned int *val);
+int pruss_cfg_update(struct pruss *pruss, unsigned int reg,
+		     unsigned int mask, unsigned int val);
+
 #else
 
 static inline struct pruss *pruss_get(struct rproc *rproc)
@@ -73,6 +163,17 @@ static inline int pruss_intc_trigger(unsigned int irq)
 	return -ENOTSUPP;
 }
 
+int pruss_cfg_read(struct pruss *pruss, unsigned int reg, unsigned int *val)
+{
+	return -ENOTSUPP;
+}
+
+int pruss_cfg_update(struct pruss *pruss, unsigned int reg,
+		     unsigned int mask, unsigned int val)
+{
+	return -ENOTSUPP;
+}
+
 #endif /* CONFIG_TI_PRUSS */
 
 #endif /* __LINUX_PRUSS_H */
-- 
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki