Author: stepan Date: Fri Apr 22 03:45:11 2011 New Revision: 6538 URL: https://tracker.coreboot.org/trac/coreboot/changeset/6538
Log: The UART divider should be calculated based on the base frequency and baudrate, not hardcoded in addition to that.
Signed-off-by: Stefan Reinauer stefan.reinauer@coreboot.org Acked-by: Peter Stuge peter@stuge.se
Modified: trunk/src/console/uart8250_console.c trunk/src/include/uart8250.h trunk/src/lib/uart8250.c trunk/src/mainboard/iwave/iWRainbowG6/Kconfig
Modified: trunk/src/console/uart8250_console.c ============================================================================== --- trunk/src/console/uart8250_console.c Thu Apr 21 23:26:58 2011 (r6537) +++ trunk/src/console/uart8250_console.c Fri Apr 22 03:45:11 2011 (r6538) @@ -25,7 +25,13 @@ { static const unsigned char div[8] = { 1, 2, 3, 6, 12, 24, 48, 96 }; int b_index = 0; - unsigned int divisor = CONFIG_TTYS0_DIV; + /* TODO the divisor calculation is hard coded to standard UARTs. Some + * UARTs won't work with these values. This should be a property of the + * UART used, worst case a Kconfig variable. For now live with hard + * codes as the only devices that might be different are the iWave + * iRainbowG6 and the OXPCIe952 card (and the latter is memory mapped) + */ + unsigned int divisor = 115200 / CONFIG_TTYS0_BAUD;
if (get_option(&b_index, "baud_rate") == 0) { divisor = div[b_index];
Modified: trunk/src/include/uart8250.h ============================================================================== --- trunk/src/include/uart8250.h Thu Apr 21 23:26:58 2011 (r6537) +++ trunk/src/include/uart8250.h Fri Apr 22 03:45:11 2011 (r6538) @@ -28,13 +28,9 @@ #ifndef CONFIG_TTYS0_BAUD #define CONFIG_TTYS0_BAUD 115200 #endif - -#ifndef CONFIG_TTYS0_DIV #if ((115200%CONFIG_TTYS0_BAUD) != 0) #error Bad ttys0 baud rate #endif -#define CONFIG_TTYS0_DIV (115200/CONFIG_TTYS0_BAUD) -#endif
/* Line Control Settings */ #ifndef CONFIG_TTYS0_LCS
Modified: trunk/src/lib/uart8250.c ============================================================================== --- trunk/src/lib/uart8250.c Thu Apr 21 23:26:58 2011 (r6537) +++ trunk/src/lib/uart8250.c Fri Apr 22 03:45:11 2011 (r6538) @@ -88,6 +88,12 @@ #if defined(__PRE_RAM__) || defined(__SMM__) void uart_init(void) { + /* TODO the divisor calculation is hard coded to standard UARTs. Some + * UARTs won't work with these values. This should be a property of the + * UART used, worst case a Kconfig variable. For now live with hard + * codes as the only devices that might be different are the iWave + * iRainbowG6 and the OXPCIe952 card (and the latter is memory mapped) + */ #if CONFIG_USE_OPTION_TABLE && !defined(__SMM__) static const unsigned char divisor[] = { 1, 2, 3, 6, 12, 24, 48, 96 }; unsigned ttys0_div, ttys0_index; @@ -97,7 +103,7 @@
uart8250_init(CONFIG_TTYS0_BASE, ttys0_div); #else - uart8250_init(CONFIG_TTYS0_BASE, CONFIG_TTYS0_DIV); + uart8250_init(CONFIG_TTYS0_BASE, (115200 / CONFIG_TTYS0_BAUD)); #endif } #endif
Modified: trunk/src/mainboard/iwave/iWRainbowG6/Kconfig ============================================================================== --- trunk/src/mainboard/iwave/iWRainbowG6/Kconfig Thu Apr 21 23:26:58 2011 (r6537) +++ trunk/src/mainboard/iwave/iWRainbowG6/Kconfig Fri Apr 22 03:45:11 2011 (r6538) @@ -37,9 +37,7 @@ int default 10
-# WTF, is this 19200? -config TTYS0_DIV - int - default 6 +# This mainboard might have a higher clocked UART or might not be able to run +# serial output at 115200 baud
endif