sparc: Serial baud rate register support multiple buses with different frequency

Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
This commit is contained in:
Daniel Hellstrom 2010-01-22 11:49:04 +01:00 committed by Francois Retief
parent 58e5585625
commit ff0b9b77c2
3 changed files with 16 additions and 4 deletions

View File

@ -120,7 +120,7 @@ static void leon2_serial_setbrg(void)
if (!gd->baudrate)
gd->baudrate = CONFIG_BAUDRATE;
scaler = leon2_serial_calc_scaler(CONFIG_SYS_CLK_FREQ, CONFIG_BAUDRATE);
scaler = leon2_serial_calc_scaler(CONFIG_SYS_CLK_FREQ, gd->baudrate);
writel(scaler, &uart->UART_Scaler);
}

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@ -20,6 +20,11 @@ DECLARE_GLOBAL_DATA_PTR;
#define CONFIG_SYS_GRLIB_APBUART_INDEX 0
#endif
static unsigned apbuart_calc_scaler(unsigned apbuart_freq, unsigned baud)
{
return (((apbuart_freq * 10) / (baud * 8)) - 5) / 10;
}
static int leon3_serial_init(void)
{
ambapp_dev_apbuart *uart;
@ -37,8 +42,11 @@ static int leon3_serial_init(void)
/* found apbuart, let's init .. */
uart = (ambapp_dev_apbuart *) apbdev.address;
/* APBUART Frequency is equal to bus frequency */
gd->arch.uart_freq = ambapp_bus_freq(&ambapp_plb, apbdev.ahb_bus_index);
/* Set scaler / baud rate */
tmp = (((CONFIG_SYS_CLK_FREQ*10) / (CONFIG_BAUDRATE*8)) - 5)/10;
tmp = apbuart_calc_scaler(gd->arch.uart_freq, CONFIG_BAUDRATE);
writel(tmp, &uart->scaler);
/* Let bit 11 be unchanged (debug bit for GRMON) */
@ -123,7 +131,10 @@ static void leon3_serial_setbrg(void)
if (!gd->baudrate)
gd->baudrate = CONFIG_BAUDRATE;
scaler = (((CONFIG_SYS_CLK_FREQ*10) / (gd->baudrate*8)) - 5)/10;
if (!gd->arch.uart_freq)
gd->arch.uart_freq = CONFIG_SYS_CLK_FREQ;
scaler = apbuart_calc_scaler(gd->arch.uart_freq, gd->baudrate);
writel(scaler, &uart->scaler);
}
@ -156,7 +167,7 @@ __weak struct serial_device *default_serial_console(void)
static inline void _debug_uart_init(void)
{
ambapp_dev_apbuart *uart = (ambapp_dev_apbuart *)CONFIG_DEBUG_UART_BASE;
uart->scaler = (((CONFIG_DEBUG_UART_CLOCK*10) / (CONFIG_BAUDRATE*8)) - 5)/10;
uart->scaler = apbuart_calc_scaler(CONFIG_DEBUG_UART_CLOCK, CONFIG_BAUDRATE);
uart->ctrl = APBUART_CTRL_RE | APBUART_CTRL_TE;
}

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@ -16,6 +16,7 @@
/* Architecture-specific global data */
struct arch_global_data {
void *uart;
unsigned int uart_freq;
};
#include <asm-generic/global_data.h>