[PATCH v4 1/2] remoteproc: st: add da to va support

[Loic Pallardy <loic.pallardy@st.com>]

ST remoteproc driver needs to provide information about
carveout memory region to allow remoteproc core to load
firmware and access trace buffer.

Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
Acked-by: Hugues Fruchet <hugues.fruchet@st.com>
Tested-by: Hugues Fruchet <hugues.fruchet@st.com>
---
Changes since V2:
- fix checkpatch --strict warning

Changes since V3:
- Rebase on rproc-next branch
---
 drivers/remoteproc/st_remoteproc.c | 43 ++++++++++++++++++++++++++++++++------
 1 file changed, 37 insertions(+), 6 deletions(-)

diff --git a/drivers/remoteproc/st_remoteproc.c b/drivers/remoteproc/st_remoteproc.c
index d534bf2..5a2cf59 100644
--- a/drivers/remoteproc/st_remoteproc.c
+++ b/drivers/remoteproc/st_remoteproc.c
@@ -21,6 +21,7 @@
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/of_reserved_mem.h>
+#include <linux/of_address.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include <linux/remoteproc.h>
@@ -53,6 +54,10 @@ struct st_rproc {
 	struct mbox_chan	*mbox_chan[ST_RPROC_MAX_VRING * MBOX_MAX];
 	struct mbox_client mbox_client_vq0;
 	struct mbox_client mbox_client_vq1;
+	phys_addr_t mem_phys;
+	phys_addr_t mem_reloc;
+	void *mem_region;
+	size_t mem_size;
 };
 
 static void st_rproc_mbox_callback(struct device *dev, u32 msg)
@@ -157,10 +162,23 @@ static int st_rproc_stop(struct rproc *rproc)
 	return sw_err ?: pwr_err;
 }
 
+static void *st_proc_da_to_va(struct rproc *rproc, u64 da, int len)
+{
+	struct st_rproc *ddata = rproc->priv;
+	int offset;
+
+	offset = da - ddata->mem_reloc;
+	if (offset < 0 || offset + len > ddata->mem_size)
+		return NULL;
+
+	return ddata->mem_region + offset;
+}
+
 static const struct rproc_ops st_rproc_ops = {
 	.kick		= st_rproc_kick,
 	.start		= st_rproc_start,
 	.stop		= st_rproc_stop,
+	.da_to_va	= st_proc_da_to_va,
 };
 
 /*
@@ -208,7 +226,8 @@ static int st_rproc_parse_dt(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct rproc *rproc = platform_get_drvdata(pdev);
 	struct st_rproc *ddata = rproc->priv;
-	struct device_node *np = dev->of_node;
+	struct device_node *np = dev->of_node, *node;
+	struct resource res;
 	int err;
 
 	if (ddata->config->sw_reset) {
@@ -252,10 +271,24 @@ static int st_rproc_parse_dt(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	err = of_reserved_mem_device_init(dev);
-	if (err) {
-		dev_err(dev, "Failed to obtain shared memory\n");
+	node = of_parse_phandle(np, "memory-region", 0);
+	if (!node) {
+		dev_err(dev, "No memory-region specified\n");
+		return -EINVAL;
+	}
+
+	err = of_address_to_resource(node, 0, &res);
+	if (err)
 		return err;
+
+	ddata->mem_phys = res.start;
+	ddata->mem_reloc = res.start;
+	ddata->mem_size = resource_size(&res);
+	ddata->mem_region = devm_ioremap_wc(dev, ddata->mem_phys, ddata->mem_size);
+	if (!ddata->mem_region) {
+		dev_err(dev, "Unable to map memory region: %pa+%zx\n",
+			&res.start, ddata->mem_size);
+		return -EBUSY;
 	}
 
 	err = clk_prepare(ddata->clk);
@@ -385,8 +418,6 @@ static int st_rproc_remove(struct platform_device *pdev)
 
 	clk_disable_unprepare(ddata->clk);
 
-	of_reserved_mem_device_release(&pdev->dev);
-
 	for (i = 0; i < ST_RPROC_MAX_VRING * MBOX_MAX; i++)
 		mbox_free_channel(ddata->mbox_chan[i]);
 
-- 
1.9.1