[PATCHv3 02/15] remoteproc/omap: Add device tree support

[Tero Kristo]

From: Suman Anna <s-anna@xxxxxx>

OMAP4+ SoCs support device tree boot only. The OMAP remoteproc
driver is enhanced to support remoteproc devices created through
Device Tree, support for legacy platform devices has been
deprecated. The current DT support handles the IPU and DSP
processor subsystems on OMAP4 and OMAP5 SoCs.

The OMAP remoteproc driver relies on the ti-sysc, reset, and
syscon layers for performing clock, reset and boot vector
management (DSP remoteprocs only) of the devices, but some of
these are limited only to the machine-specific layers
in arch/arm. The dependency against control module API for boot
vector management of the DSP remoteprocs has now been removed
with added logic to parse the boot register from the DT node
and program it appropriately directly within the driver.

The OMAP remoteproc driver expects the firmware names to be
provided via device tree entries (firmware-name.) These are used
to load the proper firmware during boot of the remote processor.

Cc: Tony Lindgren <tony@xxxxxxxxxxx>
Signed-off-by: Suman Anna <s-anna@xxxxxx>
[t-kristo@xxxxxx: converted to use ti-sysc framework]
Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
---
 drivers/remoteproc/omap_remoteproc.c | 191 +++++++++++++++++++++++----
 1 file changed, 168 insertions(+), 23 deletions(-)

diff --git a/drivers/remoteproc/omap_remoteproc.c b/drivers/remoteproc/omap_remoteproc.c
index 6398194075aa..558634624590 100644
--- a/drivers/remoteproc/omap_remoteproc.c
+++ b/drivers/remoteproc/omap_remoteproc.c
@@ -2,7 +2,7 @@
 /*
  * OMAP Remote Processor driver
  *
- * Copyright (C) 2011 Texas Instruments, Inc.
+ * Copyright (C) 2011-2019 Texas Instruments Incorporated - http://www.ti.com/
  * Copyright (C) 2011 Google, Inc.
  *
  * Ohad Ben-Cohen <ohad@xxxxxxxxxx>
@@ -16,27 +16,53 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/err.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/dma-mapping.h>
 #include <linux/remoteproc.h>
 #include <linux/mailbox_client.h>
 #include <linux/omap-mailbox.h>
-
-#include <linux/platform_data/remoteproc-omap.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+#include <linux/reset.h>
 
 #include "omap_remoteproc.h"
 #include "remoteproc_internal.h"
 
+/**
+ * struct omap_rproc_boot_data - boot data structure for the DSP omap rprocs
+ * @syscon: regmap handle for the system control configuration module
+ * @boot_reg: boot register offset within the @syscon regmap
+ */
+struct omap_rproc_boot_data {
+	struct regmap *syscon;
+	unsigned int boot_reg;
+};
+
 /**
  * struct omap_rproc - omap remote processor state
  * @mbox: mailbox channel handle
  * @client: mailbox client to request the mailbox channel
+ * @boot_data: boot data structure for setting processor boot address
  * @rproc: rproc handle
+ * @reset: reset handle
  */
 struct omap_rproc {
 	struct mbox_chan *mbox;
 	struct mbox_client client;
+	struct omap_rproc_boot_data *boot_data;
 	struct rproc *rproc;
+	struct reset_control *reset;
+};
+
+/**
+ * struct omap_rproc_dev_data - device data for the omap remote processor
+ * @device_name: device name of the remote processor
+ * @has_bootreg: true if this remote processor has boot register
+ */
+struct omap_rproc_dev_data {
+	const char *device_name;
+	bool has_bootreg;
 };
 
 /**
@@ -92,6 +118,21 @@ static void omap_rproc_kick(struct rproc *rproc, int vqid)
 			ret);
 }
 
+/**
+ * omap_rproc_write_dsp_boot_addr - set boot address for a DSP remote processor
+ * @rproc: handle of a remote processor
+ *
+ * Set boot address for a supported DSP remote processor.
+ */
+static void omap_rproc_write_dsp_boot_addr(struct rproc *rproc)
+{
+	struct omap_rproc *oproc = rproc->priv;
+	struct omap_rproc_boot_data *bdata = oproc->boot_data;
+	u32 offset = bdata->boot_reg;
+
+	regmap_write(bdata->syscon, offset, rproc->bootaddr);
+}
+
 /*
  * Power up the remote processor.
  *
@@ -103,13 +144,11 @@ static int omap_rproc_start(struct rproc *rproc)
 {
 	struct omap_rproc *oproc = rproc->priv;
 	struct device *dev = rproc->dev.parent;
-	struct platform_device *pdev = to_platform_device(dev);
-	struct omap_rproc_pdata *pdata = pdev->dev.platform_data;
 	int ret;
 	struct mbox_client *client = &oproc->client;
 
-	if (pdata->set_bootaddr)
-		pdata->set_bootaddr(rproc->bootaddr);
+	if (oproc->boot_data)
+		omap_rproc_write_dsp_boot_addr(rproc);
 
 	client->dev = dev;
 	client->tx_done = NULL;
@@ -117,7 +156,7 @@ static int omap_rproc_start(struct rproc *rproc)
 	client->tx_block = false;
 	client->knows_txdone = false;
 
-	oproc->mbox = omap_mbox_request_channel(client, pdata->mbox_name);
+	oproc->mbox = mbox_request_channel(client, 0);
 	if (IS_ERR(oproc->mbox)) {
 		ret = -EBUSY;
 		dev_err(dev, "mbox_request_channel failed: %ld\n",
@@ -138,11 +177,7 @@ static int omap_rproc_start(struct rproc *rproc)
 		goto put_mbox;
 	}
 
-	ret = pdata->device_enable(pdev);
-	if (ret) {
-		dev_err(dev, "omap_device_enable failed: %d\n", ret);
-		goto put_mbox;
-	}
+	reset_control_deassert(oproc->reset);
 
 	return 0;
 
@@ -154,15 +189,9 @@ static int omap_rproc_start(struct rproc *rproc)
 /* power off the remote processor */
 static int omap_rproc_stop(struct rproc *rproc)
 {
-	struct device *dev = rproc->dev.parent;
-	struct platform_device *pdev = to_platform_device(dev);
-	struct omap_rproc_pdata *pdata = pdev->dev.platform_data;
 	struct omap_rproc *oproc = rproc->priv;
-	int ret;
 
-	ret = pdata->device_shutdown(pdev);
-	if (ret)
-		return ret;
+	reset_control_assert(oproc->reset);
 
 	mbox_free_channel(oproc->mbox);
 
@@ -175,12 +204,122 @@ static const struct rproc_ops omap_rproc_ops = {
 	.kick		= omap_rproc_kick,
 };
 
+static const struct omap_rproc_dev_data omap4_dsp_dev_data = {
+	.device_name	= "dsp",
+	.has_bootreg	= true,
+};
+
+static const struct omap_rproc_dev_data omap4_ipu_dev_data = {
+	.device_name	= "ipu",
+};
+
+static const struct omap_rproc_dev_data omap5_dsp_dev_data = {
+	.device_name	= "dsp",
+	.has_bootreg	= true,
+};
+
+static const struct omap_rproc_dev_data omap5_ipu_dev_data = {
+	.device_name	= "ipu",
+};
+
+static const struct of_device_id omap_rproc_of_match[] = {
+	{
+		.compatible     = "ti,omap4-dsp",
+		.data           = &omap4_dsp_dev_data,
+	},
+	{
+		.compatible     = "ti,omap4-ipu",
+		.data           = &omap4_ipu_dev_data,
+	},
+	{
+		.compatible     = "ti,omap5-dsp",
+		.data           = &omap5_dsp_dev_data,
+	},
+	{
+		.compatible     = "ti,omap5-ipu",
+		.data           = &omap5_ipu_dev_data,
+	},
+	{
+		/* end */
+	},
+};
+MODULE_DEVICE_TABLE(of, omap_rproc_of_match);
+
+static const char *omap_rproc_get_firmware(struct platform_device *pdev)
+{
+	const char *fw_name;
+	int ret;
+
+	ret = of_property_read_string(pdev->dev.of_node, "firmware-name",
+				      &fw_name);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return fw_name;
+}
+
+static int omap_rproc_get_boot_data(struct platform_device *pdev,
+				    struct rproc *rproc)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct omap_rproc *oproc = rproc->priv;
+	const struct omap_rproc_dev_data *data;
+	int ret;
+
+	data = of_device_get_match_data(&pdev->dev);
+	if (!data)
+		return -ENODEV;
+
+	if (!data->has_bootreg)
+		return 0;
+
+	oproc->boot_data = devm_kzalloc(&pdev->dev, sizeof(*oproc->boot_data),
+					GFP_KERNEL);
+	if (!oproc->boot_data)
+		return -ENOMEM;
+
+	if (!of_property_read_bool(np, "ti,bootreg")) {
+		dev_err(&pdev->dev, "ti,bootreg property is missing\n");
+		return -EINVAL;
+	}
+
+	oproc->boot_data->syscon =
+			syscon_regmap_lookup_by_phandle(np, "ti,bootreg");
+	if (IS_ERR(oproc->boot_data->syscon)) {
+		ret = PTR_ERR(oproc->boot_data->syscon);
+		return ret;
+	}
+
+	if (of_property_read_u32_index(np, "ti,bootreg", 1,
+				       &oproc->boot_data->boot_reg)) {
+		dev_err(&pdev->dev, "couldn't get the boot register\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int omap_rproc_probe(struct platform_device *pdev)
 {
-	struct omap_rproc_pdata *pdata = pdev->dev.platform_data;
+	struct device_node *np = pdev->dev.of_node;
 	struct omap_rproc *oproc;
 	struct rproc *rproc;
+	const char *firmware;
 	int ret;
+	struct reset_control *reset;
+
+	if (!np) {
+		dev_err(&pdev->dev, "only DT-based devices are supported\n");
+		return -ENODEV;
+	}
+
+	reset = devm_reset_control_array_get_optional_exclusive(&pdev->dev);
+	if (IS_ERR(reset))
+		return PTR_ERR(reset);
+
+	firmware = omap_rproc_get_firmware(pdev);
+	if (IS_ERR(firmware))
+		return PTR_ERR(firmware);
 
 	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
 	if (ret) {
@@ -188,16 +327,21 @@ static int omap_rproc_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	rproc = rproc_alloc(&pdev->dev, pdata->name, &omap_rproc_ops,
-			    pdata->firmware, sizeof(*oproc));
+	rproc = rproc_alloc(&pdev->dev, dev_name(&pdev->dev), &omap_rproc_ops,
+			    firmware, sizeof(*oproc));
 	if (!rproc)
 		return -ENOMEM;
 
 	oproc = rproc->priv;
 	oproc->rproc = rproc;
+	oproc->reset = reset;
 	/* All existing OMAP IPU and DSP processors have an MMU */
 	rproc->has_iommu = true;
 
+	ret = omap_rproc_get_boot_data(pdev, rproc);
+	if (ret)
+		goto free_rproc;
+
 	platform_set_drvdata(pdev, rproc);
 
 	ret = rproc_add(rproc);
@@ -226,6 +370,7 @@ static struct platform_driver omap_rproc_driver = {
 	.remove = omap_rproc_remove,
 	.driver = {
 		.name = "omap-rproc",
+		.of_match_table = omap_rproc_of_match,
 	},
 };
 
-- 
2.17.1

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