memory: tegra: Add memory controller channels support

From Tegra186 onwards, the memory controller supports multiple channels.
Add support for mapping the address spaces of these channels and specify
the number of channels supported by Tegra186, Tegra194 and Tegra234.

In case of old bindings, channels won't be present. If channels are not
present then print a warning and continue so that backward compatibility
will be preserved in driver.

During error interrupts from memory controller, appropriate registers
from these channels need to be accessed for logging error info.

Signed-off-by: Ashish Mhetre <amhetre@nvidia.com>
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20220506132312.3910637-4-thierry.reding@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

drivers/memory/tegra/tegra186.c

@@ -48,8 +48,37 @@ static void tegra186_mc_program_sid(struct tegra_mc *mc)
 
 static int tegra186_mc_probe(struct tegra_mc *mc)
 {
+	struct platform_device *pdev = to_platform_device(mc->dev);
+	unsigned int i;
+	char name[8];
 	int err;
 
+	mc->bcast_ch_regs = devm_platform_ioremap_resource_byname(pdev, "broadcast");
+	if (IS_ERR(mc->bcast_ch_regs)) {
+		if (PTR_ERR(mc->bcast_ch_regs) == -EINVAL) {
+			dev_warn(&pdev->dev,
+				 "Broadcast channel is missing, please update your device-tree\n");
+			mc->bcast_ch_regs = NULL;
+			goto populate;
+		}
+
+		return PTR_ERR(mc->bcast_ch_regs);
+	}
+
+	mc->ch_regs = devm_kcalloc(mc->dev, mc->soc->num_channels, sizeof(*mc->ch_regs),
+				   GFP_KERNEL);
+	if (!mc->ch_regs)
+		return -ENOMEM;
+
+	for (i = 0; i < mc->soc->num_channels; i++) {
+		snprintf(name, sizeof(name), "ch%u", i);
+
+		mc->ch_regs[i] = devm_platform_ioremap_resource_byname(pdev, name);
+		if (IS_ERR(mc->ch_regs[i]))
+			return PTR_ERR(mc->ch_regs[i]);
+	}
+
+populate:
 	err = of_platform_populate(mc->dev->of_node, NULL, NULL, mc->dev);
 	if (err < 0)
 		return err;
@@ -875,6 +904,7 @@ const struct tegra_mc_soc tegra186_mc_soc = {
 	.num_clients = ARRAY_SIZE(tegra186_mc_clients),
 	.clients = tegra186_mc_clients,
 	.num_address_bits = 40,
+	.num_channels = 4,
 	.ops = &tegra186_mc_ops,
 };
 #endif

drivers/memory/tegra/tegra194.c

@@ -1347,5 +1347,6 @@ const struct tegra_mc_soc tegra194_mc_soc = {
 	.num_clients = ARRAY_SIZE(tegra194_mc_clients),
 	.clients = tegra194_mc_clients,
 	.num_address_bits = 40,
+	.num_channels = 16,
 	.ops = &tegra186_mc_ops,
 };

drivers/memory/tegra/tegra234.c

@@ -97,5 +97,6 @@ const struct tegra_mc_soc tegra234_mc_soc = {
 	.num_clients = ARRAY_SIZE(tegra234_mc_clients),
 	.clients = tegra234_mc_clients,
 	.num_address_bits = 40,
+	.num_channels = 16,
 	.ops = &tegra186_mc_ops,
 };

include/soc/tegra/mc.h

@@ -194,6 +194,7 @@ struct tegra_mc_soc {
 	unsigned int atom_size;
 
 	u8 client_id_mask;
+	u8 num_channels;
 
 	const struct tegra_smmu_soc *smmu;
 
@@ -212,6 +213,8 @@ struct tegra_mc {
 	struct tegra_smmu *smmu;
 	struct gart_device *gart;
 	void __iomem *regs;
+	void __iomem *bcast_ch_regs;
+	void __iomem **ch_regs;
 	struct clk *clk;
 	int irq;