soc/tegra: fuse: Add nvmem keepout list

On Tegra186 and later, various FUSE offsets are restricted and cannot be
accessed from CCPLEX. Currently nvmem binary interface allows reading
such offsets from userspace, which results in RAS errors.

Add nvmem keepout lists to avoid any reads to restricted offsets.
Signed-off-by: Kartik <kkartik@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/soc/tegra/fuse/fuse-tegra.c

@@ -149,6 +149,8 @@ static int tegra_fuse_probe(struct platform_device *pdev)
 	nvmem.owner = THIS_MODULE;
 	nvmem.cells = fuse->soc->cells;
 	nvmem.ncells = fuse->soc->num_cells;
+	nvmem.keepout = fuse->soc->keepouts;
+	nvmem.nkeepout = fuse->soc->num_keepouts;
 	nvmem.type = NVMEM_TYPE_OTP;
 	nvmem.read_only = true;
 	nvmem.root_only = true;

drivers/soc/tegra/fuse/fuse-tegra30.c

@@ -9,6 +9,7 @@
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/nvmem-consumer.h>
+#include <linux/nvmem-provider.h>
 #include <linux/of_device.h>
 #include <linux/of_address.h>
 #include <linux/platform_device.h>
@@ -494,6 +495,14 @@ static const struct nvmem_cell_lookup tegra186_fuse_lookups[] = {
 	},
 };
 
+static const struct nvmem_keepout tegra186_fuse_keepouts[] = {
+	{ .start = 0x01c, .end = 0x0f0 },
+	{ .start = 0x138, .end = 0x198 },
+	{ .start = 0x1d8, .end = 0x250 },
+	{ .start = 0x280, .end = 0x290 },
+	{ .start = 0x340, .end = 0x344 }
+};
+
 static const struct tegra_fuse_info tegra186_fuse_info = {
 	.read = tegra30_fuse_read,
 	.size = 0x478,
@@ -507,6 +516,8 @@ const struct tegra_fuse_soc tegra186_fuse_soc = {
 	.num_lookups = ARRAY_SIZE(tegra186_fuse_lookups),
 	.cells = tegra186_fuse_cells,
 	.num_cells = ARRAY_SIZE(tegra186_fuse_cells),
+	.keepouts = tegra186_fuse_keepouts,
+	.num_keepouts = ARRAY_SIZE(tegra186_fuse_keepouts),
 	.soc_attr_group = &tegra_soc_attr_group,
 	.clk_suspend_on = false,
 };
@@ -576,6 +587,15 @@ static const struct nvmem_cell_lookup tegra194_fuse_lookups[] = {
 	},
 };
 
+static const struct nvmem_keepout tegra194_fuse_keepouts[] = {
+	{ .start = 0x01c, .end = 0x0b8 },
+	{ .start = 0x12c, .end = 0x198 },
+	{ .start = 0x1a0, .end = 0x1bc },
+	{ .start = 0x1d8, .end = 0x250 },
+	{ .start = 0x270, .end = 0x290 },
+	{ .start = 0x310, .end = 0x45c }
+};
+
 static const struct tegra_fuse_info tegra194_fuse_info = {
 	.read = tegra30_fuse_read,
 	.size = 0x650,
@@ -589,6 +609,8 @@ const struct tegra_fuse_soc tegra194_fuse_soc = {
 	.num_lookups = ARRAY_SIZE(tegra194_fuse_lookups),
 	.cells = tegra194_fuse_cells,
 	.num_cells = ARRAY_SIZE(tegra194_fuse_cells),
+	.keepouts = tegra194_fuse_keepouts,
+	.num_keepouts = ARRAY_SIZE(tegra194_fuse_keepouts),
 	.soc_attr_group = &tegra194_soc_attr_group,
 	.clk_suspend_on = false,
 };
@@ -625,6 +647,20 @@ static const struct nvmem_cell_lookup tegra234_fuse_lookups[] = {
 	},
 };
 
+static const struct nvmem_keepout tegra234_fuse_keepouts[] = {
+	{ .start = 0x01c, .end = 0x0c8 },
+	{ .start = 0x12c, .end = 0x184 },
+	{ .start = 0x190, .end = 0x198 },
+	{ .start = 0x1a0, .end = 0x204 },
+	{ .start = 0x21c, .end = 0x250 },
+	{ .start = 0x25c, .end = 0x2f0 },
+	{ .start = 0x310, .end = 0x3d8 },
+	{ .start = 0x400, .end = 0x4f0 },
+	{ .start = 0x4f8, .end = 0x7e8 },
+	{ .start = 0x8d0, .end = 0x8d8 },
+	{ .start = 0xacc, .end = 0xf00 }
+};
+
 static const struct tegra_fuse_info tegra234_fuse_info = {
 	.read = tegra30_fuse_read,
 	.size = 0x98c,
@@ -638,6 +674,8 @@ const struct tegra_fuse_soc tegra234_fuse_soc = {
 	.num_lookups = ARRAY_SIZE(tegra234_fuse_lookups),
 	.cells = tegra234_fuse_cells,
 	.num_cells = ARRAY_SIZE(tegra234_fuse_cells),
+	.keepouts = tegra234_fuse_keepouts,
+	.num_keepouts = ARRAY_SIZE(tegra234_fuse_keepouts),
 	.soc_attr_group = &tegra194_soc_attr_group,
 	.clk_suspend_on = false,
 };

drivers/soc/tegra/fuse/fuse.h

@@ -34,6 +34,8 @@ struct tegra_fuse_soc {
 	unsigned int num_lookups;
 	const struct nvmem_cell_info *cells;
 	unsigned int num_cells;
+	const struct nvmem_keepout *keepouts;
+	unsigned int num_keepouts;
 
 	const struct attribute_group *soc_attr_group;