1 files changed, 239 insertions, 0 deletions
diff --git a/drivers/soc/tegra/fuse/tegra-apbmisc.c b/drivers/soc/tegra/fuse/tegra-apbmisc.c
new file mode 100644
index 000000000..3351bd872
--- /dev/null
+++ b/drivers/soc/tegra/fuse/tegra-apbmisc.c
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014, NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+
+#include <soc/tegra/fuse.h>
+#include <soc/tegra/common.h>
+
+#include "fuse.h"
+
+#define FUSE_SKU_INFO	0x10
+
+#define ERD_ERR_CONFIG 0x120c
+#define ERD_MASK_INBAND_ERR 0x1
+
+#define PMC_STRAPPING_OPT_A_RAM_CODE_SHIFT	4
+#define PMC_STRAPPING_OPT_A_RAM_CODE_MASK_LONG	\
+	(0xf << PMC_STRAPPING_OPT_A_RAM_CODE_SHIFT)
+#define PMC_STRAPPING_OPT_A_RAM_CODE_MASK_SHORT	\
+	(0x3 << PMC_STRAPPING_OPT_A_RAM_CODE_SHIFT)
+
+static void __iomem *apbmisc_base;
+static bool long_ram_code;
+static u32 strapping;
+static u32 chipid;
+
+u32 tegra_read_chipid(void)
+{
+	WARN(!chipid, "Tegra APB MISC not yet available\n");
+
+	return chipid;
+}
+
+u8 tegra_get_chip_id(void)
+{
+	return (tegra_read_chipid() >> 8) & 0xff;
+}
+
+u8 tegra_get_major_rev(void)
+{
+	return (tegra_read_chipid() >> 4) & 0xf;
+}
+
+u8 tegra_get_minor_rev(void)
+{
+	return (tegra_read_chipid() >> 16) & 0xf;
+}
+
+u8 tegra_get_platform(void)
+{
+	return (tegra_read_chipid() >> 20) & 0xf;
+}
+
+bool tegra_is_silicon(void)
+{
+	switch (tegra_get_chip_id()) {
+	case TEGRA194:
+	case TEGRA234:
+		if (tegra_get_platform() == 0)
+			return true;
+
+		return false;
+	}
+
+	/*
+	 * Chips prior to Tegra194 have a different way of determining whether
+	 * they are silicon or not. Since we never supported simulation on the
+	 * older Tegra chips, don't bother extracting the information and just
+	 * report that we're running on silicon.
+	 */
+	return true;
+}
+
+u32 tegra_read_straps(void)
+{
+	WARN(!chipid, "Tegra ABP MISC not yet available\n");
+
+	return strapping;
+}
+
+u32 tegra_read_ram_code(void)
+{
+	u32 straps = tegra_read_straps();
+
+	if (long_ram_code)
+		straps &= PMC_STRAPPING_OPT_A_RAM_CODE_MASK_LONG;
+	else
+		straps &= PMC_STRAPPING_OPT_A_RAM_CODE_MASK_SHORT;
+
+	return straps >> PMC_STRAPPING_OPT_A_RAM_CODE_SHIFT;
+}
+EXPORT_SYMBOL_GPL(tegra_read_ram_code);
+
+/*
+ * The function sets ERD(Error Response Disable) bit.
+ * This allows to mask inband errors and always send an
+ * OKAY response from CBB to the master which caused error.
+ */
+int tegra194_miscreg_mask_serror(void)
+{
+	if (!apbmisc_base)
+		return -EPROBE_DEFER;
+
+	if (!of_machine_is_compatible("nvidia,tegra194")) {
+		WARN(1, "Only supported for Tegra194 devices!\n");
+		return -EOPNOTSUPP;
+	}
+
+	writel_relaxed(ERD_MASK_INBAND_ERR,
+		       apbmisc_base + ERD_ERR_CONFIG);
+
+	return 0;
+}
+EXPORT_SYMBOL(tegra194_miscreg_mask_serror);
+
+static const struct of_device_id apbmisc_match[] __initconst = {
+	{ .compatible = "nvidia,tegra20-apbmisc", },
+	{ .compatible = "nvidia,tegra186-misc", },
+	{ .compatible = "nvidia,tegra194-misc", },
+	{ .compatible = "nvidia,tegra234-misc", },
+	{},
+};
+
+void __init tegra_init_revision(void)
+{
+	u8 chip_id, minor_rev;
+
+	chip_id = tegra_get_chip_id();
+	minor_rev = tegra_get_minor_rev();
+
+	switch (minor_rev) {
+	case 1:
+		tegra_sku_info.revision = TEGRA_REVISION_A01;
+		break;
+	case 2:
+		tegra_sku_info.revision = TEGRA_REVISION_A02;
+		break;
+	case 3:
+		if (chip_id == TEGRA20 && (tegra_fuse_read_spare(18) ||
+					   tegra_fuse_read_spare(19)))
+			tegra_sku_info.revision = TEGRA_REVISION_A03p;
+		else
+			tegra_sku_info.revision = TEGRA_REVISION_A03;
+		break;
+	case 4:
+		tegra_sku_info.revision = TEGRA_REVISION_A04;
+		break;
+	default:
+		tegra_sku_info.revision = TEGRA_REVISION_UNKNOWN;
+	}
+
+	tegra_sku_info.sku_id = tegra_fuse_read_early(FUSE_SKU_INFO);
+}
+
+void __init tegra_init_apbmisc(void)
+{
+	void __iomem *strapping_base;
+	struct resource apbmisc, straps;
+	struct device_node *np;
+
+	np = of_find_matching_node(NULL, apbmisc_match);
+	if (!np) {
+		/*
+		 * Fall back to legacy initialization for 32-bit ARM only. All
+		 * 64-bit ARM device tree files for Tegra are required to have
+		 * an APBMISC node.
+		 *
+		 * This is for backwards-compatibility with old device trees
+		 * that didn't contain an APBMISC node.
+		 */
+		if (IS_ENABLED(CONFIG_ARM) && soc_is_tegra()) {
+			/* APBMISC registers (chip revision, ...) */
+			apbmisc.start = 0x70000800;
+			apbmisc.end = 0x70000863;
+			apbmisc.flags = IORESOURCE_MEM;
+
+			/* strapping options */
+			if (of_machine_is_compatible("nvidia,tegra124")) {
+				straps.start = 0x7000e864;
+				straps.end = 0x7000e867;
+			} else {
+				straps.start = 0x70000008;
+				straps.end = 0x7000000b;
+			}
+
+			straps.flags = IORESOURCE_MEM;
+
+			pr_warn("Using APBMISC region %pR\n", &apbmisc);
+			pr_warn("Using strapping options registers %pR\n",
+				&straps);
+		} else {
+			/*
+			 * At this point we're not running on Tegra, so play
+			 * nice with multi-platform kernels.
+			 */
+			return;
+		}
+	} else {
+		/*
+		 * Extract information from the device tree if we've found a
+		 * matching node.
+		 */
+		if (of_address_to_resource(np, 0, &apbmisc) < 0) {
+			pr_err("failed to get APBMISC registers\n");
+			goto put;
+		}
+
+		if (of_address_to_resource(np, 1, &straps) < 0) {
+			pr_err("failed to get strapping options registers\n");
+			goto put;
+		}
+	}
+
+	apbmisc_base = ioremap(apbmisc.start, resource_size(&apbmisc));
+	if (!apbmisc_base) {
+		pr_err("failed to map APBMISC registers\n");
+	} else {
+		chipid = readl_relaxed(apbmisc_base + 4);
+	}
+
+	strapping_base = ioremap(straps.start, resource_size(&straps));
+	if (!strapping_base) {
+		pr_err("failed to map strapping options registers\n");
+	} else {
+		strapping = readl_relaxed(strapping_base);
+		iounmap(strapping_base);
+	}
+
+	long_ram_code = of_property_read_bool(np, "nvidia,long-ram-code");
+
+put:
+	of_node_put(np);
+}