diff options
author | Zhiwu Song <zhiwu.song@csr.com> | 2011-08-30 19:20:34 -0700 |
---|---|---|
committer | Barry Song <21cnbao@gmail.com> | 2011-09-11 09:17:53 +0800 |
commit | 684f741446f7a3108b4c167faf20214c42b7eeac (patch) | |
tree | 7d6b2d4919640170f61aaaf5460e9b2a6dbb24cd /arch/arm | |
parent | 858ba703e842f4ece6680b45862ee9e6e6297d1e (diff) |
ARM: CSR: add rtc i/o bridge interface for SiRFprimaII
The module is a bridge between the RTC clock domain and the CPU interface
clock domain. ARM access the register of SYSRTC, GPSRTC and PWRC through
this module.
Signed-off-by: Zhiwu Song <zhiwu.song@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Reviewed-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arm')
-rw-r--r-- | arch/arm/boot/dts/prima2-cb.dts | 2 | ||||
-rw-r--r-- | arch/arm/mach-prima2/Makefile | 1 | ||||
-rw-r--r-- | arch/arm/mach-prima2/rtciobrg.c | 139 |
3 files changed, 141 insertions, 1 deletions
diff --git a/arch/arm/boot/dts/prima2-cb.dts b/arch/arm/boot/dts/prima2-cb.dts index af86931bdcc..17b6737c4ee 100644 --- a/arch/arm/boot/dts/prima2-cb.dts +++ b/arch/arm/boot/dts/prima2-cb.dts @@ -363,7 +363,7 @@ }; rtc-iobg { - compatible = "sirf,prima2-rtciobg", "simple-bus"; + compatible = "sirf,prima2-rtciobg", "sirf-prima2-rtciobg-bus"; #address-cells = <1>; #size-cells = <1>; reg = <0x80030000 0x10000>; diff --git a/arch/arm/mach-prima2/Makefile b/arch/arm/mach-prima2/Makefile index 7af7fc05d56..f49d70b8685 100644 --- a/arch/arm/mach-prima2/Makefile +++ b/arch/arm/mach-prima2/Makefile @@ -3,5 +3,6 @@ obj-y += irq.o obj-y += clock.o obj-y += rstc.o obj-y += prima2.o +obj-y += rtciobrg.o obj-$(CONFIG_DEBUG_LL) += lluart.o obj-$(CONFIG_CACHE_L2X0) += l2x0.o diff --git a/arch/arm/mach-prima2/rtciobrg.c b/arch/arm/mach-prima2/rtciobrg.c new file mode 100644 index 00000000000..9d80f1e20a9 --- /dev/null +++ b/arch/arm/mach-prima2/rtciobrg.c @@ -0,0 +1,139 @@ +/* + * RTC I/O Bridge interfaces for CSR SiRFprimaII + * ARM access the registers of SYSRTC, GPSRTC and PWRC through this module + * + * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company. + * + * Licensed under GPLv2 or later. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/of_platform.h> + +#define SIRFSOC_CPUIOBRG_CTRL 0x00 +#define SIRFSOC_CPUIOBRG_WRBE 0x04 +#define SIRFSOC_CPUIOBRG_ADDR 0x08 +#define SIRFSOC_CPUIOBRG_DATA 0x0c + +/* + * suspend asm codes will access this address to make system deepsleep + * after DRAM becomes self-refresh + */ +void __iomem *sirfsoc_rtciobrg_base; +static DEFINE_SPINLOCK(rtciobrg_lock); + +/* + * symbols without lock are only used by suspend asm codes + * and these symbols are not exported too + */ +void sirfsoc_rtc_iobrg_wait_sync(void) +{ + while (readl_relaxed(sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_CTRL)) + cpu_relax(); +} + +void sirfsoc_rtc_iobrg_besyncing(void) +{ + unsigned long flags; + + spin_lock_irqsave(&rtciobrg_lock, flags); + + sirfsoc_rtc_iobrg_wait_sync(); + + spin_unlock_irqrestore(&rtciobrg_lock, flags); +} +EXPORT_SYMBOL_GPL(sirfsoc_rtc_iobrg_besyncing); + +u32 __sirfsoc_rtc_iobrg_readl(u32 addr) +{ + sirfsoc_rtc_iobrg_wait_sync(); + + writel_relaxed(0x00, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_WRBE); + writel_relaxed(addr, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_ADDR); + writel_relaxed(0x01, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_CTRL); + + sirfsoc_rtc_iobrg_wait_sync(); + + return readl_relaxed(sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_DATA); +} + +u32 sirfsoc_rtc_iobrg_readl(u32 addr) +{ + unsigned long flags, val; + + spin_lock_irqsave(&rtciobrg_lock, flags); + + val = __sirfsoc_rtc_iobrg_readl(addr); + + spin_unlock_irqrestore(&rtciobrg_lock, flags); + + return val; +} +EXPORT_SYMBOL_GPL(sirfsoc_rtc_iobrg_readl); + +void sirfsoc_rtc_iobrg_pre_writel(u32 val, u32 addr) +{ + sirfsoc_rtc_iobrg_wait_sync(); + + writel_relaxed(0xf1, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_WRBE); + writel_relaxed(addr, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_ADDR); + + writel_relaxed(val, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_DATA); +} + +void sirfsoc_rtc_iobrg_writel(u32 val, u32 addr) +{ + unsigned long flags; + + spin_lock_irqsave(&rtciobrg_lock, flags); + + sirfsoc_rtc_iobrg_pre_writel(val, addr); + + writel_relaxed(0x01, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_CTRL); + + sirfsoc_rtc_iobrg_wait_sync(); + + spin_unlock_irqrestore(&rtciobrg_lock, flags); +} +EXPORT_SYMBOL_GPL(sirfsoc_rtc_iobrg_writel); + +static const struct of_device_id rtciobrg_ids[] = { + { .compatible = "sirf,prima2-rtciobg" }, + {} +}; + +static int __devinit sirfsoc_rtciobrg_probe(struct platform_device *op) +{ + struct device_node *np = op->dev.of_node; + + sirfsoc_rtciobrg_base = of_iomap(np, 0); + if (!sirfsoc_rtciobrg_base) + panic("unable to map rtc iobrg registers\n"); + + return 0; +} + +static struct platform_driver sirfsoc_rtciobrg_driver = { + .probe = sirfsoc_rtciobrg_probe, + .driver = { + .name = "sirfsoc-rtciobrg", + .owner = THIS_MODULE, + .of_match_table = rtciobrg_ids, + }, +}; + +static int __init sirfsoc_rtciobrg_init(void) +{ + return platform_driver_register(&sirfsoc_rtciobrg_driver); +} +postcore_initcall(sirfsoc_rtciobrg_init); + +MODULE_AUTHOR("Zhiwu Song <zhiwu.song@csr.com>, " + "Barry Song <baohua.song@csr.com>"); +MODULE_DESCRIPTION("CSR SiRFprimaII rtc io bridge"); +MODULE_LICENSE("GPL"); |