Re: [PATCH v11 3/3] dmaengine: add driver for Sophgo CV18XX/SG200X dmamux

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Le 11/08/2024 à 07:16, Inochi Amaoto a écrit :
Sophgo CV18XX/SG200X use DW AXI CORE with a multiplexer for remapping
its request lines. The multiplexer supports at most 8 request lines.

Add driver for Sophgo CV18XX/SG200X DMA multiplexer.

Signed-off-by: Inochi Amaoto <inochiama@xxxxxxxxxxx>
---

Hi,

...

+static void *cv1800_dmamux_route_allocate(struct of_phandle_args *dma_spec,
+					  struct of_dma *ofdma)
+{
+	struct platform_device *pdev = of_find_device_by_node(ofdma->of_node);
+	struct cv1800_dmamux_data *dmamux = platform_get_drvdata(pdev);
+	struct cv1800_dmamux_map *map;
+	struct llist_node *node;
+	unsigned long flags;
+	unsigned int chid, devid, cpuid;
+	int ret;
+
+	if (dma_spec->args_count != DMAMUX_NCELLS) {
+		dev_err(&pdev->dev, "invalid number of dma mux args\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	devid = dma_spec->args[0];
+	cpuid = dma_spec->args[1];
+	dma_spec->args_count = 1;
+
+	if (devid > MAX_DMA_MAPPING_ID) {
+		dev_err(&pdev->dev, "invalid device id: %u\n", devid);
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (cpuid > MAX_DMA_CPU_ID) {
+		dev_err(&pdev->dev, "invalid cpu id: %u\n", cpuid);
+		return ERR_PTR(-EINVAL);
+	}
+
+	dma_spec->np = of_parse_phandle(ofdma->of_node, "dma-masters", 0);
+	if (!dma_spec->np) {
+		dev_err(&pdev->dev, "can't get dma master\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	spin_lock_irqsave(&dmamux->lock, flags);
+
+	if (test_bit(devid, dmamux->mapped_peripherals)) {
+		llist_for_each_entry(map, dmamux->reserve_maps.first, node) {
+			if (map->peripheral == devid && map->cpu == cpuid)
+				goto found;
+		}
+
+		ret = -EINVAL;
+		goto failed;
+	} else {
+		node = llist_del_first(&dmamux->free_maps);
+		if (!node) {
+			ret = -ENODEV;
+			goto failed;
+		}
+
+		map = llist_entry(node, struct cv1800_dmamux_map, node);
+		llist_add(&map->node, &dmamux->reserve_maps);
+		set_bit(devid, dmamux->mapped_peripherals);
+	}
+
+found:
+	chid = map->channel;
+	map->peripheral = devid;
+	map->cpu = cpuid;
+
+	regmap_set_bits(dmamux->regmap,
+			DMAMUX_CH_REG(chid),
+			DMAMUX_CH_SET(chid, devid));
+
+	regmap_update_bits(dmamux->regmap, CV1800_SDMA_DMA_INT_MUX,
+			   DMAMUX_INT_CH_MASK(chid, cpuid),
+			   DMAMUX_INT_CH_BIT(chid, cpuid));
+
+	spin_unlock_irqrestore(&dmamux->lock, flags);
+
+	dma_spec->args[0] = chid;
+
+	dev_dbg(&pdev->dev, "register channel %u for req %u (cpu %u)\n",
+		chid, devid, cpuid);
+
+	return map;
+
+failed:
+	spin_unlock_irqrestore(&dmamux->lock, flags);
+	of_node_put(dma_spec->np);
+	dev_err(&pdev->dev, "errno %d\n", ret);
+	return ERR_PTR(ret);
+

Nitpick: Unneeded empty new line.

+}
+
+static int cv1800_dmamux_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *mux_node = dev->of_node;
+	struct cv1800_dmamux_data *data;
+	struct cv1800_dmamux_map *tmp;
+	struct device *parent = dev->parent;
+	struct regmap *regmap = NULL;
+	unsigned int i;
+
+	if (!parent)
+		return -ENODEV;
+
+	regmap = device_node_to_regmap(parent->of_node);
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	data = devm_kmalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	spin_lock_init(&data->lock);
+	init_llist_head(&data->free_maps);

Why init free_maps and not reserve_maps?
'data' is not zeroed, so it should be needed, IMHO.

Same for mapped_peripherals. It is not initialized.

I think that using devm_kzalloc() above is needed. (and init_llist_head(&data->free_maps) could then be removed, if you want)

Just my 2c.

+
+	for (i = 0; i <= MAX_DMA_CH_ID; i++) {
+		tmp = devm_kmalloc(dev, sizeof(*tmp), GFP_KERNEL);
+		if (!tmp) {
+			/* It is OK for not allocating all channel */
+			dev_warn(dev, "can not allocate channel %u\n", i);
+			continue;
+		}
+
+		init_llist_node(&tmp->node);
+		tmp->channel = i;
+		llist_add(&tmp->node, &data->free_maps);
+	}
+
+	/* if no channel is allocated, the probe must fail */
+	if (llist_empty(&data->free_maps))
+		return -ENOMEM;
+
+	data->regmap = regmap;
+	data->dmarouter.dev = dev;
+	data->dmarouter.route_free = cv1800_dmamux_free;
+
+	platform_set_drvdata(pdev, data);
+
+	return of_dma_router_register(mux_node,
+				      cv1800_dmamux_route_allocate,
+				      &data->dmarouter);
+}

...

CJ






[Index of Archives]     [Linux Kernel]     [Linux ARM (vger)]     [Linux ARM MSM]     [Linux Omap]     [Linux Arm]     [Linux Tegra]     [Fedora ARM]     [Linux for Samsung SOC]     [eCos]     [Linux PCI]     [Linux Fastboot]     [Gcc Help]     [Git]     [DCCP]     [IETF Announce]     [Security]     [Linux MIPS]     [Yosemite Campsites]

  Powered by Linux