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| author | Stelian Pop <stelian@popies.net> | 2008-05-08 14:52:34 +0200 |
|---|---|---|
| committer | Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> | 2008-05-10 11:45:03 +0200 |
| commit | 19883aede2ac0a522493bfb2b35a7dbb200071b1 (patch) | |
| tree | 0cfee61893ab65993b6e56ad4f2590de7031a9d9 /board/atmel | |
| parent | 098b7b4b441b12c2a64dd517930f43c793542759 (diff) | |
| download | u-boot-imx-19883aede2ac0a522493bfb2b35a7dbb200071b1.zip u-boot-imx-19883aede2ac0a522493bfb2b35a7dbb200071b1.tar.gz u-boot-imx-19883aede2ac0a522493bfb2b35a7dbb200071b1.tar.bz2 | |
Support AT91CAP9 revC CPUs
The AT91CAP9 revC CPU has a few differences over the previous,
revB CPU which was distributed in small quantities only (revA was
an internal Atmel product only).
The revC silicon needs a special initialisation sequence to
switch from the internal (imprecise) RC oscillator to the
external 32k clock.
Signed-off-by: Stelian Pop <stelian@popies.net>
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Diffstat (limited to 'board/atmel')
| -rw-r--r-- | board/atmel/at91cap9adk/at91cap9adk.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/board/atmel/at91cap9adk/at91cap9adk.c b/board/atmel/at91cap9adk/at91cap9adk.c index e353cea..a3eaf19 100644 --- a/board/atmel/at91cap9adk/at91cap9adk.c +++ b/board/atmel/at91cap9adk/at91cap9adk.c @@ -72,6 +72,33 @@ static void at91cap9_serial_hw_init(void) #endif } +static void at91cap9_slowclock_hw_init(void) +{ + /* + * On AT91CAP9 revC CPUs, the slow clock can be based on an + * internal impreciseRC oscillator or an external 32kHz oscillator. + * Switch to the latter. + */ +#define ARCH_ID_AT91CAP9_REVB 0x399 +#define ARCH_ID_AT91CAP9_REVC 0x601 + if (at91_sys_read(AT91_PMC_VER) == ARCH_ID_AT91CAP9_REVC) { + unsigned i, tmp = at91_sys_read(AT91_SCKCR); + if ((tmp & AT91CAP9_SCKCR_OSCSEL) == AT91CAP9_SCKCR_OSCSEL_RC) { + extern void timer_init(void); + timer_init(); + tmp |= AT91CAP9_SCKCR_OSC32EN; + at91_sys_write(AT91_SCKCR, tmp); + for (i = 0; i < 1200; i++) + udelay(1000); + tmp |= AT91CAP9_SCKCR_OSCSEL_32; + at91_sys_write(AT91_SCKCR, tmp); + udelay(200); + tmp &= ~AT91CAP9_SCKCR_RCEN; + at91_sys_write(AT91_SCKCR, tmp); + } + } +} + static void at91cap9_nor_hw_init(void) { unsigned long csa; @@ -305,6 +332,7 @@ int board_init(void) gd->bd->bi_boot_params = PHYS_SDRAM + 0x100; at91cap9_serial_hw_init(); + at91cap9_slowclock_hw_init(); at91cap9_nor_hw_init(); #ifdef CONFIG_CMD_NAND at91cap9_nand_hw_init(); |