Hi Lee,

On 09/02/2015 10:38 AM, Lee Jones wrote:

nit, can you please move st_rproc_stop function after st_rproc_start,
same order as in fw_ops, for better flow.

+
+static int st_rproc_start(struct rproc *rproc)
+{
+	struct st_rproc *ddata = rproc->priv;
+	int err;
+
+	regmap_update_bits(ddata->boot_base, ddata->boot_offset,
+			   ddata->config->bootaddr_mask, rproc->bootaddr);
+
+	err = clk_enable(ddata->clk);
+	if (err) {
+		dev_err(&rproc->dev, "Failed to enable clock\n");
+		return err;
+	}
+
+	if (ddata->config->sw_reset) {
+		err = reset_control_deassert(ddata->sw_reset);
+		if (err) {
+			dev_err(&rproc->dev, "Failed to deassert S/W Reset\n");
+			goto sw_reset_fail;
+		}
+	}
+
+	if (ddata->config->pwr_reset) {
+		err = reset_control_deassert(ddata->pwr_reset);
+		if (err) {
+			dev_err(&rproc->dev, "Failed to deassert Power Reset\n");
+			goto pwr_reset_fail;
+		}
+	}
+
+	dev_info(&rproc->dev, "Started from 0x%x\n", rproc->bootaddr);
+
+	return 0;
+
+
+pwr_reset_fail:
+	reset_control_assert(ddata->sw_reset);

Should this be under a check for (ddata->config->sw_reset). It is not
clear from code whether the sw_reset and pwr_reset are exclusive of each
of other or have both.

+sw_reset_fail:
+	clk_disable(ddata->clk);
+
+	return err;
+}
+
+static struct rproc_ops st_rproc_ops = {
+	.start		= st_rproc_start,
+	.stop		= st_rproc_stop,
+};
+
+/*
+ * Fetch state of the processor: 0 is off, 1 is on.
+ */
+static int st_rproc_state(struct platform_device *pdev)
+{
+	struct rproc *rproc = platform_get_drvdata(pdev);
+	struct st_rproc *ddata = rproc->priv;
+	int reset_sw = 0, reset_pwr = 0;
+
+	if (ddata->config->sw_reset)
+		reset_sw = reset_control_status(ddata->sw_reset);
+
+	if (ddata->config->pwr_reset)
+		reset_pwr = reset_control_status(ddata->pwr_reset);
+
+	if (reset_sw < 0 || reset_pwr < 0)
+		return -EINVAL;
+
+	return !reset_sw && !reset_pwr;
+}
+
+static const struct st_rproc_config st40_rproc_cfg = {
+	.sw_reset = true,
+	.pwr_reset = true,
+	.bootaddr_mask = GENMASK(28, 1),
+};
+
+static const struct st_rproc_config st231_rproc_cfg = {
+	.sw_reset = true,
+	.pwr_reset = false,
+	.bootaddr_mask = GENMASK(31, 6),
+};
+
+static const struct of_device_id st_rproc_match[] = {
+	{ .compatible = "st,st40-rproc", .data = &st40_rproc_cfg },
+	{ .compatible = "st,st231-rproc", .data = &st231_rproc_cfg },
+	{},
+};
+MODULE_DEVICE_TABLE(of, st_rproc_match);
+
+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 resource	*mem;
+	int err;
+
+	if (ddata->config->sw_reset) {
+		ddata->sw_reset = devm_reset_control_get(dev, "sw_reset");
+		if (IS_ERR(ddata->sw_reset)) {
+			dev_err(dev, "Failed to get S/W Reset\n");
+			return PTR_ERR(ddata->sw_reset);
+		}
+	}
+
+	if (ddata->config->pwr_reset) {
+		ddata->pwr_reset = devm_reset_control_get(dev, "pwr_reset");
+		if (IS_ERR(ddata->pwr_reset)) {
+			dev_err(dev, "Failed to get Power Reset\n");
+			return PTR_ERR(ddata->pwr_reset);
+		}
+	}
+
+	ddata->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(ddata->clk)) {
+		dev_err(dev, "Failed to get clock\n");
+		return PTR_ERR(ddata->clk);
+	}
+
+	err = of_property_read_u32(np, "clock-frequency", &ddata->clk_rate);
+	if (err) {
+		dev_err(dev, "failed to get clock frequency\n");
+		return err;
+	}
+
+	ddata->boot_base = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
+	if (!ddata->boot_base) {
+		dev_err(dev, "Boot base not found\n");
+		return -EINVAL;
+	}
+
+	err = of_property_read_u32_index(np, "st,syscfg", 1,
+					 &ddata->boot_offset);
+	if (err) {
+		dev_err(dev, "Boot offset not found\n");
+		return -EINVAL;
+	}
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem) {
+		dev_err(dev, "no rproc memory definition\n");
+		return -ENXIO;
+	}
+
+	if (!devm_request_mem_region(dev, mem->start,
+				     resource_size(mem), pdev->name)) {
+		dev_err(dev, "failed to get memory region resource\n");
+		return -EBUSY;
+	}
+	err = dmam_declare_coherent_memory(dev, mem->start, mem->start,
+					  resource_size(mem),
+					  DMA_MEMORY_MAP |
+					  DMA_MEMORY_EXCLUSIVE);
+	if (err < 0) {
+		dev_err(dev, "cannot declare coherent memory: %d\n", err);
+		return -ENXIO;
+	}

What kind of memory will this be? If this a carveout memory being
set-aside from DDR, you may want to use a reserved-memory node entry,
with a "memory-region" property added to the rproc device node and use
of_reserved_mem_device_init() and of_reserved_mem_device_release() API,
following the standard semantics of reserved-memory as in
Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt.

Obviously that will need a change in the binding as well.

+
+	err = clk_prepare(ddata->clk);
+	if (err)
+		dev_err(dev, "failed to get clock\n");
+
+	return err;
+}
+
+static int st_rproc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct of_device_id *match;
+	struct st_rproc *ddata;
+	struct device_node *np = dev->of_node;
+	struct rproc *rproc;
+	int enabled;
+	int ret;
+
+	match = of_match_device((st_rproc_match), dev);
+	if (!match || !match->data) {
+		dev_err(dev, "No device match found\n");
+		return -ENODEV;
+	}
+
+	rproc = rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
+	if (!rproc)
+		return -ENOMEM;
+
+	ddata = rproc->priv;
+	ddata->config = (struct st_rproc_config *)match->data;

I believe Ohad's preference is to explicitly set rproc->has_iommu to false.

+
+	platform_set_drvdata(pdev, rproc);
+
+	ret = st_rproc_parse_dt(pdev);
+	if (ret)
+		goto free_rproc;
+
+	enabled = st_rproc_state(pdev);
+	if (enabled < 0)
+		goto free_rproc;
+
+	if (enabled) {
+		atomic_inc(&rproc->power);
+		rproc->state = RPROC_RUNNING;

I am curious about this change, who are you expecting to have booted the
processor before the driver is probed?

+	} else {
+		clk_set_rate(ddata->clk, ddata->clk_rate);
+	}
+
+	ret = rproc_add(rproc);
+	if (ret)
+		goto free_rproc;
+
+	return 0;
+
+free_rproc:
+	rproc_put(rproc);
+	return ret;
+}
+
+static int st_rproc_remove(struct platform_device *pdev)
+{
+	struct rproc *rproc = platform_get_drvdata(pdev);
+	struct st_rproc *ddata = rproc->priv;
+
+	rproc_del(rproc);
+
+	clk_disable_unprepare(ddata->clk);
+
+	rproc_put(rproc);
+
+	return 0;
+}
+
+static struct platform_driver st_rproc_driver = {
+	.probe = st_rproc_probe,
+	.remove = st_rproc_remove,
+	.driver = {
+		.name = "st-rproc",
+		.of_match_table = of_match_ptr(st_rproc_match),
+	},
+};
+module_platform_driver(st_rproc_driver);
+
+MODULE_DESCRIPTION("ST Remote Processor Control Driver");
+MODULE_AUTHOR("Ludovic Barre [off-list ref]");
+MODULE_LICENSE("GPL v2");