diff options
| author | Simon Glass <sjg@chromium.org> | 2011-11-28 15:04:37 +0000 |
|---|---|---|
| committer | Albert ARIBAUD <albert.u.boot@aribaud.net> | 2011-12-24 10:23:32 +0100 |
| commit | 8442fd3c6a82def9beac46ab683f2fd4bf8f8f14 (patch) | |
| tree | 0f972b7244ae9980f4924f91e356f72e2b71103d | |
| parent | 905ed41aad2f80b64b1163a55e18ee4e5278e708 (diff) | |
| download | u-boot-midas-8442fd3c6a82def9beac46ab683f2fd4bf8f8f14.tar.gz u-boot-midas-8442fd3c6a82def9beac46ab683f2fd4bf8f8f14.tar.bz2 u-boot-midas-8442fd3c6a82def9beac46ab683f2fd4bf8f8f14.zip | |
tegra: add clock_ll_start_uart() to enable UART prior to reloc
Most boards will want to enable a UART early. This function provides
that feature in Tegra architecture code so the code does not need to be
copied on every board.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
| -rw-r--r-- | arch/arm/cpu/armv7/tegra2/clock.c | 14 | ||||
| -rw-r--r-- | arch/arm/include/asm/arch-tegra2/clock.h | 11 |
2 files changed, 25 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/tegra2/clock.c b/arch/arm/cpu/armv7/tegra2/clock.c index 03ac1e3ed0..11d2346d83 100644 --- a/arch/arm/cpu/armv7/tegra2/clock.c +++ b/arch/arm/cpu/armv7/tegra2/clock.c @@ -904,6 +904,20 @@ static int clock_set_rate(enum clock_id clkid, u32 n, u32 m, u32 p, u32 cpcon) return 0; } +void clock_ll_start_uart(enum periph_id periph_id) +{ + /* Assert UART reset and enable clock */ + reset_set_enable(periph_id, 1); + clock_enable(periph_id); + clock_ll_set_source(periph_id, 0); /* UARTx_CLK_SRC = 00, PLLP_OUT0 */ + + /* wait for 2us */ + udelay(2); + + /* De-assert reset to UART */ + reset_set_enable(periph_id, 0); +} + int clock_verify(void) { struct clk_pll *pll = get_pll(CLOCK_ID_PERIPH); diff --git a/arch/arm/include/asm/arch-tegra2/clock.h b/arch/arm/include/asm/arch-tegra2/clock.h index 49e9904b57..080ef18e81 100644 --- a/arch/arm/include/asm/arch-tegra2/clock.h +++ b/arch/arm/include/asm/arch-tegra2/clock.h @@ -344,6 +344,17 @@ unsigned clock_adjust_periph_pll_div(enum periph_id periph_id, */ unsigned clock_get_rate(enum clock_id clkid); +/** + * Start up a UART using low-level calls + * + * Prior to relocation clock_start_periph_pll() cannot be called. This + * function provides a way to set up a UART using low-level calls which + * do not require BSS. + * + * @param periph_id Peripheral ID of UART to enable (e,g, PERIPH_ID_UART1) + */ +void clock_ll_start_uart(enum periph_id periph_id); + /* * Checks that clocks are valid and prints a warning if not * |