soc: ti: pruss: enable support for ICSSG subsystems on K3 AM65x SoCs

The K3 AM65x family of SoCs have the next generation of the PRU-ICSS
processor subsystem capable of supporting Gigabit Ethernet, and is
commonly referred to as ICSSG. These SoCs contain typically three
ICSSG instances named ICSSG0, ICSSG1 and ICSSG2. The three ICSSGs are
identical to each other for the most part with minor SoC integration
differences and capabilities. The ICSSG2 supports slightly enhanced
features like SGMII mode Ethernet, while the ICSS0 and ICSSG1 instances
are limited to MII mode only.

The ICSSGs on K3 AM65x SoCs are in general super-sets of the PRUSS on the
AM57xx/66AK2G SoCs. They include two additional auxiliary PRU cores called
RTUs and few other additional sub-modules. The interrupt integration is
also different on the K3 AM65x SoCs and are propagated through various
SoC-level Interrupt Router and Interrupt Aggregator blocks. Other IP level
differences include different constant tables, differences in system event
interrupt input sources etc. They also do not have a programmable module
reset line like those present on AM33xx/AM43xx SoCs. The modules are reset
just like any other IP with the SoC's global cold/warm resets.

The existing pruss_soc_bus and pruss platform drivers have been updated to
support these new ICSSG instances through new AM65x specific compatibles.
A build dependency with ARCH_K3 is added to enable building all the
existing PRUSS platform drivers for this ARMv8 platform.

Signed-off-by: Suman Anna <s-anna@ti.com>

drivers/soc/ti/Kconfig

@@ -90,7 +90,7 @@ config TI_SCI_PM_DOMAINS
 
 config TI_PRUSS
 	tristate "TI PRU-ICSS Subsystem Platform drivers"
-	depends on SOC_AM33XX || SOC_AM43XX || SOC_DRA7XX || ARCH_KEYSTONE
+	depends on SOC_AM33XX || SOC_AM43XX || SOC_DRA7XX || ARCH_KEYSTONE || ARCH_K3
 	select MFD_SYSCON
 	help
 	  TI PRU-ICSS Subsystem platform specific support.

drivers/soc/ti/pruss.c

@@ -63,8 +63,9 @@ struct pruss *pruss_get(struct rproc *rproc)
 	if (!dev->parent)
 		return ERR_PTR(-ENODEV);
 
-	/* rudimentary check to make sure rproc handle is for a PRU */
-	if (!strstr(dev_name(dev->parent), "pru"))
+	/* rudimentary check to make sure rproc handle is for a PRU or RTU */
+	if (!strstr(dev_name(dev->parent), "pru") &&
+	    !strstr(dev_name(dev->parent), "rtu"))
 		return ERR_PTR(-ENODEV);
 
 	ppdev = to_platform_device(dev->parent->parent);
@@ -402,6 +403,7 @@ static const struct of_device_id pruss_of_match[] = {
 	{ .compatible = "ti,am4376-pruss", .data = &am437x_match_data, },
 	{ .compatible = "ti,am5728-pruss", .data = NULL, },
 	{ .compatible = "ti,k2g-pruss", .data = NULL, },
+	{ .compatible = "ti,am654-icssg", .data = NULL, },
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, pruss_of_match);

drivers/soc/ti/pruss_soc_bus.c

@@ -290,6 +290,7 @@ static const struct of_device_id pruss_soc_bus_of_match[] = {
 	{ .compatible = "ti,am4376-pruss-soc-bus", .data = &am437x_data, },
 	{ .compatible = "ti,am5728-pruss-soc-bus", .data = &am57xx_data, },
 	{ .compatible = "ti,k2g-pruss-soc-bus", .data = &k2g_data, },
+	{ .compatible = "ti,am654-icssg-soc-bus", .data = &k2g_data, },
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, pruss_soc_bus_of_match);