diff options
Diffstat (limited to 'cpu/arm920t/cpu.c')
-rw-r--r-- | cpu/arm920t/cpu.c | 124 |
1 files changed, 10 insertions, 114 deletions
diff --git a/cpu/arm920t/cpu.c b/cpu/arm920t/cpu.c index 1b9cde6..87c1adc 100644 --- a/cpu/arm920t/cpu.c +++ b/cpu/arm920t/cpu.c @@ -32,62 +32,13 @@ #include <common.h> #include <command.h> #include <arm920t.h> +#include <asm/system.h> #ifdef CONFIG_USE_IRQ DECLARE_GLOBAL_DATA_PTR; #endif -/* read co-processor 15, register #1 (control register) */ -static unsigned long read_p15_c1 (void) -{ - unsigned long value; - - __asm__ __volatile__( - "mrc p15, 0, %0, c1, c0, 0 @ read control reg\n" - : "=r" (value) - : - : "memory"); - -#ifdef MMU_DEBUG - printf ("p15/c1 is = %08lx\n", value); -#endif - return value; -} - -/* write to co-processor 15, register #1 (control register) */ -static void write_p15_c1 (unsigned long value) -{ -#ifdef MMU_DEBUG - printf ("write %08lx to p15/c1\n", value); -#endif - __asm__ __volatile__( - "mcr p15, 0, %0, c1, c0, 0 @ write it back\n" - : - : "r" (value) - : "memory"); - - read_p15_c1 (); -} - -static void cp_delay (void) -{ - volatile int i; - - /* copro seems to need some delay between reading and writing */ - for (i = 0; i < 100; i++); -} - -/* See also ARM920T Technical reference Manual */ -#define C1_MMU (1<<0) /* mmu off/on */ -#define C1_ALIGN (1<<1) /* alignment faults off/on */ -#define C1_DC (1<<2) /* dcache off/on */ - -#define C1_BIG_ENDIAN (1<<7) /* big endian off/on */ -#define C1_SYS_PROT (1<<8) /* system protection */ -#define C1_ROM_PROT (1<<9) /* ROM protection */ -#define C1_IC (1<<12) /* icache off/on */ -#define C1_HIGH_VECTORS (1<<13) /* location of vectors: low/high addresses */ - +static void cache_flush(void); int cpu_init (void) { @@ -110,76 +61,21 @@ int cleanup_before_linux (void) * we turn off caches etc ... */ - unsigned long i; - disable_interrupts (); /* turn off I/D-cache */ - asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i)); - i &= ~(C1_DC | C1_IC); - asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i)); - + icache_disable(); + dcache_disable(); /* flush I/D-cache */ - i = 0; - asm ("mcr p15, 0, %0, c7, c7, 0": :"r" (i)); + cache_flush(); - return (0); -} - -int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) -{ - disable_interrupts (); - reset_cpu (0); - /*NOTREACHED*/ - return (0); -} - -void icache_enable (void) -{ - ulong reg; - - reg = read_p15_c1 (); /* get control reg. */ - cp_delay (); - write_p15_c1 (reg | C1_IC); -} - -void icache_disable (void) -{ - ulong reg; - - reg = read_p15_c1 (); - cp_delay (); - write_p15_c1 (reg & ~C1_IC); -} - -int icache_status (void) -{ - return (read_p15_c1 () & C1_IC) != 0; -} - -#ifdef USE_920T_MMU -/* It makes no sense to use the dcache if the MMU is not enabled */ -void dcache_enable (void) -{ - ulong reg; - - reg = read_p15_c1 (); - cp_delay (); - write_p15_c1 (reg | C1_DC); + return 0; } -void dcache_disable (void) +/* flush I/D-cache */ +static void cache_flush (void) { - ulong reg; + unsigned long i = 0; - reg = read_p15_c1 (); - cp_delay (); - reg &= ~C1_DC; - write_p15_c1 (reg); -} - -int dcache_status (void) -{ - return (read_p15_c1 () & C1_DC) != 0; + asm ("mcr p15, 0, %0, c7, c7, 0": :"r" (i)); } -#endif |