remoteproc: Add support for TI power processor

Many TI System on Chip (SoC) solutions do have a dedicated
microcontroller for doing power management functionality. These include
the AM335x, AM437x, Keystone K2G SoCs. The functionality provided by
these microcontrollers and the communication mechanisms vary very
widely. However, we are able to consolidate some basic functionality to
be generic enough starting with K2G SoC family. Introduce a basic remote
proc driver to support these microcontrollers. In fact, on SoCs starting
with K2G, basic power management functions are primarily accessible for
the High Level Operating Systems(HLOS) via these microcontroller solutions.

Hence, having these started at a bootloader level is pretty much
mandatory.

Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

drivers/remoteproc/Kconfig

@@ -21,4 +21,14 @@ config REMOTEPROC_SANDBOX
 	help
 	  Say 'y' here to add support for test processor which does dummy
 	  operations for sandbox platform.
+
+config REMOTEPROC_TI_POWER
+	bool "Support for TI Power processor"
+	select REMOTEPROC
+	depends on DM
+	depends on ARCH_KEYSTONE
+	depends on OF_CONTROL
+	help
+	  Say 'y' here to add support for TI power processors such as those
+	  found on certain TI keystone and OMAP generation SoCs.
 endmenu

drivers/remoteproc/Makefile

@@ -8,3 +8,4 @@ obj-$(CONFIG_REMOTEPROC) += rproc-uclass.o
 
 # Remote proc drivers - Please keep this list alphabetically sorted.
 obj-$(CONFIG_REMOTEPROC_SANDBOX) += sandbox_testproc.o
+obj-$(CONFIG_REMOTEPROC_TI_POWER) += ti_power_proc.o

drivers/remoteproc/ti_power_proc.c

@@ -0,0 +1,180 @@
+/*
+ * (C) Copyright 2015-2016
+ * Texas Instruments Incorporated - http://www.ti.com/
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#define pr_fmt(fmt) "%s: " fmt, __func__
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <remoteproc.h>
+#include <mach/psc_defs.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/**
+ * struct ti_powerproc_privdata - power processor private data
+ * @loadaddr:	base address for loading the power processor
+ * @psc_module:	psc module address.
+ */
+struct ti_powerproc_privdata {
+	phys_addr_t loadaddr;
+	u32 psc_module;
+};
+
+/**
+ * ti_of_to_priv() - generate private data from device tree
+ * @dev:	corresponding ti remote processor device
+ * @priv:	pointer to driver specific private data
+ *
+ * Return: 0 if all went ok, else corresponding -ve error
+ */
+static int ti_of_to_priv(struct udevice *dev,
+			 struct ti_powerproc_privdata *priv)
+{
+	int node = dev->of_offset;
+	const void *blob = gd->fdt_blob;
+	int tmp;
+
+	if (!blob) {
+		debug("'%s' no dt?\n", dev->name);
+		return -EINVAL;
+	}
+
+	priv->loadaddr = fdtdec_get_addr(blob, node, "reg");
+	if (priv->loadaddr == FDT_ADDR_T_NONE) {
+		debug("'%s': no 'reg' property\n", dev->name);
+		return -EINVAL;
+	}
+
+	tmp = fdtdec_get_int(blob, node, "ti,lpsc_module", -EINVAL);
+	if (tmp < 0) {
+		debug("'%s': no 'ti,lpsc_module' property\n", dev->name);
+		return tmp;
+	}
+	priv->psc_module = tmp;
+
+	return 0;
+}
+
+/**
+ * ti_powerproc_probe() - Basic probe
+ * @dev:	corresponding ti remote processor device
+ *
+ * Return: 0 if all went ok, else corresponding -ve error
+ */
+static int ti_powerproc_probe(struct udevice *dev)
+{
+	struct dm_rproc_uclass_pdata *uc_pdata;
+	struct ti_powerproc_privdata *priv;
+	int ret;
+
+	uc_pdata = dev_get_uclass_platdata(dev);
+	priv = dev_get_priv(dev);
+
+	ret = ti_of_to_priv(dev, priv);
+
+	debug("%s probed with slave_addr=0x%08lX module=%d(%d)\n",
+	      uc_pdata->name, priv->loadaddr, priv->psc_module, ret);
+
+	return ret;
+}
+
+/**
+ * ti_powerproc_load() - Loadup the TI remote processor
+ * @dev:	corresponding ti remote processor device
+ * @addr:	Address in memory where image binary is stored
+ * @size:	Size in bytes of the image binary
+ *
+ * Return: 0 if all went ok, else corresponding -ve error
+ */
+static int ti_powerproc_load(struct udevice *dev, ulong addr, ulong size)
+{
+	struct dm_rproc_uclass_pdata *uc_pdata;
+	struct ti_powerproc_privdata *priv;
+	int ret;
+
+	uc_pdata = dev_get_uclass_platdata(dev);
+	if (!uc_pdata) {
+		debug("%s: no uc pdata!\n", dev->name);
+		return -EINVAL;
+	}
+
+	priv = dev_get_priv(dev);
+	ret = psc_module_keep_in_reset_enabled(priv->psc_module, false);
+	if (ret) {
+		debug("%s Unable to disable module '%d'(ret=%d)\n",
+		      uc_pdata->name, priv->psc_module, ret);
+		return ret;
+	}
+
+	debug("%s: Loading binary from 0x%08lX, size 0x%08lX to 0x%08lX\n",
+	      uc_pdata->name, addr, size, priv->loadaddr);
+
+	memcpy((void *)priv->loadaddr, (void *)addr, size);
+
+	debug("%s: Complete!\n", uc_pdata->name);
+	return 0;
+}
+
+/**
+ * ti_powerproc_start() - (replace: short desc)
+ * @dev:	corresponding ti remote processor device
+ *
+ * Return: 0 if all went ok, else corresponding -ve error
+ */
+static int ti_powerproc_start(struct udevice *dev)
+{
+	struct dm_rproc_uclass_pdata *uc_pdata;
+	struct ti_powerproc_privdata *priv;
+	int ret;
+
+	uc_pdata = dev_get_uclass_platdata(dev);
+	if (!uc_pdata) {
+		debug("%s: no uc pdata!\n", dev->name);
+		return -EINVAL;
+	}
+
+	priv = dev_get_priv(dev);
+	ret = psc_disable_module(priv->psc_module);
+	if (ret) {
+		debug("%s Unable to disable module '%d'(ret=%d)\n",
+		      uc_pdata->name, priv->psc_module, ret);
+		return ret;
+	}
+
+	ret = psc_module_release_from_reset(priv->psc_module);
+	if (ret) {
+		debug("%s Failed to wait for module '%d'(ret=%d)\n",
+		      uc_pdata->name, priv->psc_module, ret);
+		return ret;
+	}
+	ret = psc_enable_module(priv->psc_module);
+	if (ret) {
+		debug("%s Unable to disable module '%d'(ret=%d)\n",
+		      uc_pdata->name, priv->psc_module, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct dm_rproc_ops ti_powerproc_ops = {
+	.load = ti_powerproc_load,
+	.start = ti_powerproc_start,
+};
+
+static const struct udevice_id ti_powerproc_ids[] = {
+	{.compatible = "ti,power-processor"},
+	{}
+};
+
+U_BOOT_DRIVER(ti_powerproc) = {
+	.name = "ti_power_proc",
+	.of_match = ti_powerproc_ids,
+	.id = UCLASS_REMOTEPROC,
+	.ops = &ti_powerproc_ops,
+	.probe = ti_powerproc_probe,
+	.priv_auto_alloc_size = sizeof(struct ti_powerproc_privdata),
+};