diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-10-08 17:37:16 -0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-10-08 17:37:16 -0400 |
commit | 8b45bc892e6842115fc87c2b2a3b86a20617606a (patch) | |
tree | 636c804eb29bb97070e7d2bc4d5ab9d1dad27cac /drivers/power/reset/at91-reset.c | |
parent | eb785bef684f2b7d03b530efc8e6f199e9777e2f (diff) | |
parent | fa637bf0595ee1796d728a0d33b6b7fff12e1f3d (diff) |
Merge tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Arnd Bergmann:
"These are changes for drivers that are intimately tied to some SoC and
for some reason could not get merged through the respective subsystem
maintainer tree.
Most of the new code is for the Keystone Navigator driver, which is
new base support that is going to be needed for their hardware
accelerated network driver and other units.
Most of the commits are for moving old code around from at91 and omap
for things that are done in device drivers nowadays.
- at91: move reset, poweroff, memory and clocksource code into
drivers directories
- socfpga: add edac driver (through arm-soc, as requested by Boris)
- omap: move omap-intc code to drivers/irqchip
- sunxi: added an RTC driver for sun6i
- omap: mailbox driver related changes
- keystone: support for the "Navigator" component
- versatile: new reboot, led and soc drivers"
* tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (92 commits)
bus: arm-ccn: Fix spurious warning message
leds: add device tree bindings for register bit LEDs
soc: add driver for the ARM RealView
power: reset: driver for the Versatile syscon reboot
leds: add a driver for syscon-based LEDs
drivers/soc: ti: fix build break with modules
MAINTAINERS: Add Keystone Multicore Navigator drivers entry
soc: ti: add Keystone Navigator DMA support
Documentation: dt: soc: add Keystone Navigator DMA bindings
soc: ti: add Keystone Navigator QMSS driver
Documentation: dt: soc: add Keystone Navigator QMSS bindings
rtc: sunxi: Depend on platforms sun4i/sun7i that actually have the rtc
rtc: sun6i: Add sun6i RTC driver
irqchip: omap-intc: remove unnecessary comments
irqchip: omap-intc: correct maximum number or MIR registers
irqchip: omap-intc: enable TURBO idle mode
irqchip: omap-intc: enable IP protection
irqchip: omap-intc: remove unnecesary of_address_to_resource() call
irqchip: omap-intc: comment style cleanup
irqchip: omap-intc: minor improvement to omap_irq_pending()
...
Diffstat (limited to 'drivers/power/reset/at91-reset.c')
-rw-r--r-- | drivers/power/reset/at91-reset.c | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c new file mode 100644 index 00000000000..3611806c9cf --- /dev/null +++ b/drivers/power/reset/at91-reset.c @@ -0,0 +1,252 @@ +/* + * Atmel AT91 SAM9 SoCs reset code + * + * Copyright (C) 2007 Atmel Corporation. + * Copyright (C) BitBox Ltd 2010 + * Copyright (C) 2011 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcosoft.com> + * Copyright (C) 2014 Free Electrons + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/reboot.h> + +#include <asm/system_misc.h> + +#include <mach/at91sam9_ddrsdr.h> +#include <mach/at91sam9_sdramc.h> + +#define AT91_RSTC_CR 0x00 /* Reset Controller Control Register */ +#define AT91_RSTC_PROCRST BIT(0) /* Processor Reset */ +#define AT91_RSTC_PERRST BIT(2) /* Peripheral Reset */ +#define AT91_RSTC_EXTRST BIT(3) /* External Reset */ +#define AT91_RSTC_KEY (0xa5 << 24) /* KEY Password */ + +#define AT91_RSTC_SR 0x04 /* Reset Controller Status Register */ +#define AT91_RSTC_URSTS BIT(0) /* User Reset Status */ +#define AT91_RSTC_RSTTYP GENMASK(10, 8) /* Reset Type */ +#define AT91_RSTC_NRSTL BIT(16) /* NRST Pin Level */ +#define AT91_RSTC_SRCMP BIT(17) /* Software Reset Command in Progress */ + +#define AT91_RSTC_MR 0x08 /* Reset Controller Mode Register */ +#define AT91_RSTC_URSTEN BIT(0) /* User Reset Enable */ +#define AT91_RSTC_URSTIEN BIT(4) /* User Reset Interrupt Enable */ +#define AT91_RSTC_ERSTL GENMASK(11, 8) /* External Reset Length */ + +enum reset_type { + RESET_TYPE_GENERAL = 0, + RESET_TYPE_WAKEUP = 1, + RESET_TYPE_WATCHDOG = 2, + RESET_TYPE_SOFTWARE = 3, + RESET_TYPE_USER = 4, +}; + +static void __iomem *at91_ramc_base[2], *at91_rstc_base; + +/* +* unless the SDRAM is cleanly shutdown before we hit the +* reset register it can be left driving the data bus and +* killing the chance of a subsequent boot from NAND +*/ +static void at91sam9260_restart(enum reboot_mode mode, const char *cmd) +{ + asm volatile( + /* Align to cache lines */ + ".balign 32\n\t" + + /* Disable SDRAM accesses */ + "str %2, [%0, #" __stringify(AT91_SDRAMC_TR) "]\n\t" + + /* Power down SDRAM */ + "str %3, [%0, #" __stringify(AT91_SDRAMC_LPR) "]\n\t" + + /* Reset CPU */ + "str %4, [%1, #" __stringify(AT91_RSTC_CR) "]\n\t" + + "b .\n\t" + : + : "r" (at91_ramc_base[0]), + "r" (at91_rstc_base), + "r" (1), + "r" (AT91_SDRAMC_LPCB_POWER_DOWN), + "r" (AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST)); +} + +static void at91sam9g45_restart(enum reboot_mode mode, const char *cmd) +{ + asm volatile( + /* + * Test wether we have a second RAM controller to care + * about. + * + * First, test that we can dereference the virtual address. + */ + "cmp %1, #0\n\t" + "beq 1f\n\t" + + /* Then, test that the RAM controller is enabled */ + "ldr r0, [%1]\n\t" + "cmp r0, #0\n\t" + + /* Align to cache lines */ + ".balign 32\n\t" + + /* Disable SDRAM0 accesses */ + "1: str %3, [%0, #" __stringify(AT91_DDRSDRC_RTR) "]\n\t" + /* Power down SDRAM0 */ + " str %4, [%0, #" __stringify(AT91_DDRSDRC_RTR) "]\n\t" + /* Disable SDRAM1 accesses */ + " strne %3, [%1, #" __stringify(AT91_DDRSDRC_RTR) "]\n\t" + /* Power down SDRAM1 */ + " strne %4, [%1, #" __stringify(AT91_DDRSDRC_RTR) "]\n\t" + /* Reset CPU */ + " str %5, [%2, #" __stringify(AT91_RSTC_CR) "]\n\t" + + " b .\n\t" + : + : "r" (at91_ramc_base[0]), + "r" (at91_ramc_base[1]), + "r" (at91_rstc_base), + "r" (1), + "r" (AT91_DDRSDRC_LPCB_POWER_DOWN), + "r" (AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST) + : "r0"); +} + +static void __init at91_reset_status(struct platform_device *pdev) +{ + u32 reg = readl(at91_rstc_base + AT91_RSTC_SR); + char *reason; + + switch ((reg & AT91_RSTC_RSTTYP) >> 8) { + case RESET_TYPE_GENERAL: + reason = "general reset"; + break; + case RESET_TYPE_WAKEUP: + reason = "wakeup"; + break; + case RESET_TYPE_WATCHDOG: + reason = "watchdog reset"; + break; + case RESET_TYPE_SOFTWARE: + reason = "software reset"; + break; + case RESET_TYPE_USER: + reason = "user reset"; + break; + default: + reason = "unknown reset"; + break; + } + + pr_info("AT91: Starting after %s\n", reason); +} + +static struct of_device_id at91_ramc_of_match[] = { + { .compatible = "atmel,at91sam9260-sdramc", }, + { .compatible = "atmel,at91sam9g45-ddramc", }, + { .compatible = "atmel,sama5d3-ddramc", }, + { /* sentinel */ } +}; + +static struct of_device_id at91_reset_of_match[] = { + { .compatible = "atmel,at91sam9260-rstc", .data = at91sam9260_restart }, + { .compatible = "atmel,at91sam9g45-rstc", .data = at91sam9g45_restart }, + { /* sentinel */ } +}; + +static int at91_reset_of_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + struct device_node *np; + int idx = 0; + + at91_rstc_base = of_iomap(pdev->dev.of_node, 0); + if (!at91_rstc_base) { + dev_err(&pdev->dev, "Could not map reset controller address\n"); + return -ENODEV; + } + + for_each_matching_node(np, at91_ramc_of_match) { + at91_ramc_base[idx] = of_iomap(np, 0); + if (!at91_ramc_base[idx]) { + dev_err(&pdev->dev, "Could not map ram controller address\n"); + return -ENODEV; + } + idx++; + } + + match = of_match_node(at91_reset_of_match, pdev->dev.of_node); + arm_pm_restart = match->data; + + return 0; +} + +static int at91_reset_platform_probe(struct platform_device *pdev) +{ + const struct platform_device_id *match; + struct resource *res; + int idx = 0; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + at91_rstc_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(at91_rstc_base)) { + dev_err(&pdev->dev, "Could not map reset controller address\n"); + return PTR_ERR(at91_rstc_base); + } + + for (idx = 0; idx < 2; idx++) { + res = platform_get_resource(pdev, IORESOURCE_MEM, idx + 1 ); + at91_ramc_base[idx] = devm_ioremap(&pdev->dev, res->start, + resource_size(res)); + if (IS_ERR(at91_ramc_base[idx])) { + dev_err(&pdev->dev, "Could not map ram controller address\n"); + return PTR_ERR(at91_ramc_base[idx]); + } + } + + match = platform_get_device_id(pdev); + arm_pm_restart = (void (*)(enum reboot_mode, const char*)) + match->driver_data; + + return 0; +} + +static int at91_reset_probe(struct platform_device *pdev) +{ + int ret; + + if (pdev->dev.of_node) + ret = at91_reset_of_probe(pdev); + else + ret = at91_reset_platform_probe(pdev); + + if (ret) + return ret; + + at91_reset_status(pdev); + + return 0; +} + +static struct platform_device_id at91_reset_plat_match[] = { + { "at91-sam9260-reset", (unsigned long)at91sam9260_restart }, + { "at91-sam9g45-reset", (unsigned long)at91sam9g45_restart }, + { /* sentinel */ } +}; + +static struct platform_driver at91_reset_driver = { + .probe = at91_reset_probe, + .driver = { + .name = "at91-reset", + .of_match_table = at91_reset_of_match, + }, + .id_table = at91_reset_plat_match, +}; +module_platform_driver(at91_reset_driver); |