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, 110 insertions, 0 deletions

diff --git a/drivers/soc/tegra/fuse/speedo-tegra20.c b/drivers/soc/tegra/fuse/speedo-tegra20.c
new file mode 100644
index 000000000000..eff1b63f330d
--- /dev/null
+++ b/drivers/soc/tegra/fuse/speedo-tegra20.c
@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2012-2014, 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/bug.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+
+#include <soc/tegra/fuse.h>
+
+#include "fuse.h"
+
+#define CPU_SPEEDO_LSBIT		20
+#define CPU_SPEEDO_MSBIT		29
+#define CPU_SPEEDO_REDUND_LSBIT		30
+#define CPU_SPEEDO_REDUND_MSBIT		39
+#define CPU_SPEEDO_REDUND_OFFS	(CPU_SPEEDO_REDUND_MSBIT - CPU_SPEEDO_MSBIT)
+
+#define CORE_SPEEDO_LSBIT		40
+#define CORE_SPEEDO_MSBIT		47
+#define CORE_SPEEDO_REDUND_LSBIT	48
+#define CORE_SPEEDO_REDUND_MSBIT	55
+#define CORE_SPEEDO_REDUND_OFFS	(CORE_SPEEDO_REDUND_MSBIT - CORE_SPEEDO_MSBIT)
+
+#define SPEEDO_MULT			4
+
+#define PROCESS_CORNERS_NUM		4
+
+#define SPEEDO_ID_SELECT_0(rev)		((rev) <= 2)
+#define SPEEDO_ID_SELECT_1(sku)		\
+	(((sku) != 20) && ((sku) != 23) && ((sku) != 24) && \
+	 ((sku) != 27) && ((sku) != 28))
+
+enum {
+	SPEEDO_ID_0,
+	SPEEDO_ID_1,
+	SPEEDO_ID_2,
+	SPEEDO_ID_COUNT,
+};
+
+static const u32 __initconst cpu_process_speedos[][PROCESS_CORNERS_NUM] = {
+	{315, 366, 420, UINT_MAX},
+	{303, 368, 419, UINT_MAX},
+	{316, 331, 383, UINT_MAX},
+};
+
+static const u32 __initconst core_process_speedos[][PROCESS_CORNERS_NUM] = {
+	{165, 195, 224, UINT_MAX},
+	{165, 195, 224, UINT_MAX},
+	{165, 195, 224, UINT_MAX},
+};
+
+void __init tegra20_init_speedo_data(struct tegra_sku_info *sku_info)
+{
+	u32 reg;
+	u32 val;
+	int i;
+
+	BUILD_BUG_ON(ARRAY_SIZE(cpu_process_speedos) != SPEEDO_ID_COUNT);
+	BUILD_BUG_ON(ARRAY_SIZE(core_process_speedos) != SPEEDO_ID_COUNT);
+
+	if (SPEEDO_ID_SELECT_0(sku_info->revision))
+		sku_info->soc_speedo_id = SPEEDO_ID_0;
+	else if (SPEEDO_ID_SELECT_1(sku_info->sku_id))
+		sku_info->soc_speedo_id = SPEEDO_ID_1;
+	else
+		sku_info->soc_speedo_id = SPEEDO_ID_2;
+
+	val = 0;
+	for (i = CPU_SPEEDO_MSBIT; i >= CPU_SPEEDO_LSBIT; i--) {
+		reg = tegra20_spare_fuse_early(i) |
+			tegra20_spare_fuse_early(i + CPU_SPEEDO_REDUND_OFFS);
+		val = (val << 1) | (reg & 0x1);
+	}
+	val = val * SPEEDO_MULT;
+	pr_debug("Tegra CPU speedo value %u\n", val);
+
+	for (i = 0; i < (PROCESS_CORNERS_NUM - 1); i++) {
+		if (val <= cpu_process_speedos[sku_info->soc_speedo_id][i])
+			break;
+	}
+	sku_info->cpu_process_id = i;
+
+	val = 0;
+	for (i = CORE_SPEEDO_MSBIT; i >= CORE_SPEEDO_LSBIT; i--) {
+		reg = tegra20_spare_fuse_early(i) |
+			tegra20_spare_fuse_early(i + CORE_SPEEDO_REDUND_OFFS);
+		val = (val << 1) | (reg & 0x1);
+	}
+	val = val * SPEEDO_MULT;
+	pr_debug("Core speedo value %u\n", val);
+
+	for (i = 0; i < (PROCESS_CORNERS_NUM - 1); i++) {
+		if (val <= core_process_speedos[sku_info->soc_speedo_id][i])
+			break;
+	}
+	sku_info->core_process_id = i;
+}