diff options
| author | Sascha Hauer <s.hauer@pengutronix.de> | 2010-03-19 10:50:55 +0100 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2010-03-19 11:18:20 +0100 |
| commit | 5443856cadac7faaaeefeed9d769f497a8c6fa4b (patch) | |
| tree | 746f366043cfa6c93205c36c42d492acbf38a7c7 | |
| parent | 3d1bc8626c7b17facfcb7fb5dee4686f47a1e75d (diff) | |
| download | op-kernel-dev-5443856cadac7faaaeefeed9d769f497a8c6fa4b.zip op-kernel-dev-5443856cadac7faaaeefeed9d769f497a8c6fa4b.tar.gz | |
i.MX51: determine silicon revision dynamically
Freescale redboot passes the silicon revision via
ATAG_REVISION. Remove this bootloader dependency by
doing the same as redboot does in the Kernel.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
| -rw-r--r-- | arch/arm/mach-mx5/cpu.c | 53 | ||||
| -rw-r--r-- | arch/arm/plat-mxc/include/mach/mx51.h | 13 |
2 files changed, 60 insertions, 6 deletions
diff --git a/arch/arm/mach-mx5/cpu.c b/arch/arm/mach-mx5/cpu.c index 41c769f..2d37785 100644 --- a/arch/arm/mach-mx5/cpu.c +++ b/arch/arm/mach-mx5/cpu.c @@ -14,9 +14,62 @@ #include <linux/types.h> #include <linux/kernel.h> #include <linux/init.h> +#include <linux/module.h> #include <mach/hardware.h> #include <asm/io.h> +static int cpu_silicon_rev = -1; + +#define SI_REV 0x48 + +static void query_silicon_parameter(void) +{ + void __iomem *rom = ioremap(MX51_IROM_BASE_ADDR, MX51_IROM_SIZE); + u32 rev; + + if (!rom) { + cpu_silicon_rev = -EINVAL; + return; + } + + rev = readl(rom + SI_REV); + switch (rev) { + case 0x1: + cpu_silicon_rev = MX51_CHIP_REV_1_0; + break; + case 0x2: + cpu_silicon_rev = MX51_CHIP_REV_1_1; + break; + case 0x10: + cpu_silicon_rev = MX51_CHIP_REV_2_0; + break; + case 0x20: + cpu_silicon_rev = MX51_CHIP_REV_3_0; + break; + default: + cpu_silicon_rev = 0; + } + + iounmap(rom); +} + +/* + * Returns: + * the silicon revision of the cpu + * -EINVAL - not a mx51 + */ +int mx51_revision(void) +{ + if (!cpu_is_mx51()) + return -EINVAL; + + if (cpu_silicon_rev == -1) + query_silicon_parameter(); + + return cpu_silicon_rev; +} +EXPORT_SYMBOL(mx51_revision); + static int __init post_cpu_init(void) { unsigned int reg; diff --git a/arch/arm/plat-mxc/include/mach/mx51.h b/arch/arm/plat-mxc/include/mach/mx51.h index f1396bd..fd255a9 100644 --- a/arch/arm/plat-mxc/include/mach/mx51.h +++ b/arch/arm/plat-mxc/include/mach/mx51.h @@ -28,6 +28,12 @@ */ /* + * IROM + */ +#define MX51_IROM_BASE_ADDR 0x0 +#define MX51_IROM_SIZE SZ_64K + +/* * IRAM */ #define MX51_IRAM_BASE_ADDR 0x1FFE0000 /* internal ram */ @@ -438,12 +444,7 @@ #if !defined(__ASSEMBLY__) && !defined(__MXC_BOOT_UNCOMPRESS) -extern unsigned int system_rev; - -static inline unsigned int mx51_revision(void) -{ - return system_rev; -} +extern int mx51_revision(void); #endif #endif /* __ASM_ARCH_MXC_MX51_H__ */ |
