soc/tegra: Add efuse driver for Tegra

Implement fuse driver for Tegra20, Tegra30, Tegra114 and Tegra124. This
replaces functionality previously provided in arch/arm/mach-tegra, which
is removed in this patch.

While at it, move the only user of the global tegra_revision variable
over to tegra_sku_info.revision and export tegra_fuse_readl() to allow
drivers to read calibration fuses.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 112 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 000000000000..bfc1d54ac4ad
--- /dev/null
+++ b/drivers/soc/tegra/fuse/tegra-apbmisc.c
@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2014, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+
+#include <soc/tegra/fuse.h>
+
+#include "fuse.h"
+
+#define APBMISC_BASE	0x70000800
+#define APBMISC_SIZE	0x64
+#define FUSE_SKU_INFO	0x10
+
+static void __iomem *apbmisc_base;
+static void __iomem *strapping_base;
+
+u32 tegra_read_chipid(void)
+{
+	return readl_relaxed(apbmisc_base + 4);
+}
+
+u8 tegra_get_chip_id(void)
+{
+	u32 id = tegra_read_chipid();
+
+	return (id >> 8) & 0xff;
+}
+
+u32 tegra_read_straps(void)
+{
+	if (strapping_base)
+		return readl_relaxed(strapping_base);
+	else
+		return 0;
+}
+
+static const struct of_device_id apbmisc_match[] __initconst = {
+	{ .compatible = "nvidia,tegra20-apbmisc", },
+	{},
+};
+
+void __init tegra_init_revision(void)
+{
+	u32 id, chip_id, minor_rev;
+	int rev;
+
+	id = tegra_read_chipid();
+	chip_id = (id >> 8) & 0xff;
+	minor_rev = (id >> 16) & 0xf;
+
+	switch (minor_rev) {
+	case 1:
+		rev = TEGRA_REVISION_A01;
+		break;
+	case 2:
+		rev = TEGRA_REVISION_A02;
+		break;
+	case 3:
+		if (chip_id == TEGRA20 && (tegra20_spare_fuse_early(18) ||
+					   tegra20_spare_fuse_early(19)))
+			rev = TEGRA_REVISION_A03p;
+		else
+			rev = TEGRA_REVISION_A03;
+		break;
+	case 4:
+		rev = TEGRA_REVISION_A04;
+		break;
+	default:
+		rev = TEGRA_REVISION_UNKNOWN;
+	}
+
+	tegra_sku_info.revision = rev;
+
+	if (chip_id == TEGRA20)
+		tegra_sku_info.sku_id = tegra20_fuse_early(FUSE_SKU_INFO);
+	else
+		tegra_sku_info.sku_id = tegra30_fuse_readl(FUSE_SKU_INFO);
+}
+
+void __init tegra_init_apbmisc(void)
+{
+	struct device_node *np;
+
+	np = of_find_matching_node(NULL, apbmisc_match);
+	apbmisc_base = of_iomap(np, 0);
+	if (!apbmisc_base) {
+		pr_warn("ioremap tegra apbmisc failed. using %08x instead\n",
+			APBMISC_BASE);
+		apbmisc_base = ioremap(APBMISC_BASE, APBMISC_SIZE);
+	}
+
+	strapping_base = of_iomap(np, 1);
+	if (!strapping_base)
+		pr_err("ioremap tegra strapping_base failed\n");
+}