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authorLinus Torvalds <torvalds@linux-foundation.org>2014-06-08 11:31:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-06-08 11:31:16 -0700
commit3f17ea6dea8ba5668873afa54628a91aaa3fb1c0 (patch)
treeafbeb2accd4c2199ddd705ae943995b143a0af02 /drivers/power/reset/keystone-reset.c
parent1860e379875dfe7271c649058aeddffe5afd9d0d (diff)
parent1a5700bc2d10cd379a795fd2bb377a190af5acd4 (diff)
Merge branch 'next' (accumulated 3.16 merge window patches) into master
Now that 3.15 is released, this merges the 'next' branch into 'master', bringing us to the normal situation where my 'master' branch is the merge window. * accumulated work in next: (6809 commits) ufs: sb mutex merge + mutex_destroy powerpc: update comments for generic idle conversion cris: update comments for generic idle conversion idle: remove cpu_idle() forward declarations nbd: zero from and len fields in NBD_CMD_DISCONNECT. mm: convert some level-less printks to pr_* MAINTAINERS: adi-buildroot-devel is moderated MAINTAINERS: add linux-api for review of API/ABI changes mm/kmemleak-test.c: use pr_fmt for logging fs/dlm/debug_fs.c: replace seq_printf by seq_puts fs/dlm/lockspace.c: convert simple_str to kstr fs/dlm/config.c: convert simple_str to kstr mm: mark remap_file_pages() syscall as deprecated mm: memcontrol: remove unnecessary memcg argument from soft limit functions mm: memcontrol: clean up memcg zoneinfo lookup mm/memblock.c: call kmemleak directly from memblock_(alloc|free) mm/mempool.c: update the kmemleak stack trace for mempool allocations lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations mm: introduce kmemleak_update_trace() mm/kmemleak.c: use %u to print ->checksum ...
Diffstat (limited to 'drivers/power/reset/keystone-reset.c')
-rw-r--r--drivers/power/reset/keystone-reset.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/drivers/power/reset/keystone-reset.c b/drivers/power/reset/keystone-reset.c
new file mode 100644
index 000000000000..408a18fd91cb
--- /dev/null
+++ b/drivers/power/reset/keystone-reset.c
@@ -0,0 +1,166 @@
+/*
+ * TI keystone reboot driver
+ *
+ * Copyright (C) 2014 Texas Instruments Incorporated. http://www.ti.com/
+ *
+ * Author: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
+#include <asm/system_misc.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_platform.h>
+
+#define RSTYPE_RG 0x0
+#define RSCTRL_RG 0x4
+#define RSCFG_RG 0x8
+#define RSISO_RG 0xc
+
+#define RSCTRL_KEY_MASK 0x0000ffff
+#define RSCTRL_RESET_MASK BIT(16)
+#define RSCTRL_KEY 0x5a69
+
+#define RSMUX_OMODE_MASK 0xe
+#define RSMUX_OMODE_RESET_ON 0xa
+#define RSMUX_OMODE_RESET_OFF 0x0
+#define RSMUX_LOCK_MASK 0x1
+#define RSMUX_LOCK_SET 0x1
+
+#define RSCFG_RSTYPE_SOFT 0x300f
+#define RSCFG_RSTYPE_HARD 0x0
+
+#define WDT_MUX_NUMBER 0x4
+
+static int rspll_offset;
+static struct regmap *pllctrl_regs;
+
+/**
+ * rsctrl_enable_rspll_write - enable access to RSCTRL, RSCFG
+ * To be able to access to RSCTRL, RSCFG registers
+ * we have to write a key before
+ */
+static inline int rsctrl_enable_rspll_write(void)
+{
+ return regmap_update_bits(pllctrl_regs, rspll_offset + RSCTRL_RG,
+ RSCTRL_KEY_MASK, RSCTRL_KEY);
+}
+
+static void rsctrl_restart(enum reboot_mode mode, const char *cmd)
+{
+ /* enable write access to RSTCTRL */
+ rsctrl_enable_rspll_write();
+
+ /* reset the SOC */
+ regmap_update_bits(pllctrl_regs, rspll_offset + RSCTRL_RG,
+ RSCTRL_RESET_MASK, 0);
+}
+
+static struct of_device_id rsctrl_of_match[] = {
+ {.compatible = "ti,keystone-reset", },
+ {},
+};
+
+static int rsctrl_probe(struct platform_device *pdev)
+{
+ int i;
+ int ret;
+ u32 val;
+ unsigned int rg;
+ u32 rsmux_offset;
+ struct regmap *devctrl_regs;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+
+ if (!np)
+ return -ENODEV;
+
+ /* get regmaps */
+ pllctrl_regs = syscon_regmap_lookup_by_phandle(np, "ti,syscon-pll");
+ if (IS_ERR(pllctrl_regs))
+ return PTR_ERR(pllctrl_regs);
+
+ devctrl_regs = syscon_regmap_lookup_by_phandle(np, "ti,syscon-dev");
+ if (IS_ERR(devctrl_regs))
+ return PTR_ERR(devctrl_regs);
+
+ ret = of_property_read_u32_index(np, "ti,syscon-pll", 1, &rspll_offset);
+ if (ret) {
+ dev_err(dev, "couldn't read the reset pll offset!\n");
+ return -EINVAL;
+ }
+
+ ret = of_property_read_u32_index(np, "ti,syscon-dev", 1, &rsmux_offset);
+ if (ret) {
+ dev_err(dev, "couldn't read the rsmux offset!\n");
+ return -EINVAL;
+ }
+
+ /* set soft/hard reset */
+ val = of_property_read_bool(np, "ti,soft-reset");
+ val = val ? RSCFG_RSTYPE_SOFT : RSCFG_RSTYPE_HARD;
+
+ ret = rsctrl_enable_rspll_write();
+ if (ret)
+ return ret;
+
+ ret = regmap_write(pllctrl_regs, rspll_offset + RSCFG_RG, val);
+ if (ret)
+ return ret;
+
+ arm_pm_restart = rsctrl_restart;
+
+ /* disable a reset isolation for all module clocks */
+ ret = regmap_write(pllctrl_regs, rspll_offset + RSISO_RG, 0);
+ if (ret)
+ return ret;
+
+ /* enable a reset for watchdogs from wdt-list */
+ for (i = 0; i < WDT_MUX_NUMBER; i++) {
+ ret = of_property_read_u32_index(np, "ti,wdt-list", i, &val);
+ if (ret == -EOVERFLOW && !i) {
+ dev_err(dev, "ti,wdt-list property has to contain at"
+ "least one entry\n");
+ return -EINVAL;
+ } else if (ret) {
+ break;
+ }
+
+ if (val >= WDT_MUX_NUMBER) {
+ dev_err(dev, "ti,wdt-list property can contain"
+ "only numbers < 4\n");
+ return -EINVAL;
+ }
+
+ rg = rsmux_offset + val * 4;
+
+ ret = regmap_update_bits(devctrl_regs, rg, RSMUX_OMODE_MASK,
+ RSMUX_OMODE_RESET_ON |
+ RSMUX_LOCK_SET);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct platform_driver rsctrl_driver = {
+ .probe = rsctrl_probe,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = KBUILD_MODNAME,
+ .of_match_table = rsctrl_of_match,
+ },
+};
+module_platform_driver(rsctrl_driver);
+
+MODULE_AUTHOR("Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>");
+MODULE_DESCRIPTION("Texas Instruments keystone reset driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" KBUILD_MODNAME);