| Message ID | 1332188824-5447-4-git-send-email-sjg@chromium.org |
|---|---|
| State | New, archived |
| Headers | show |
On 03/19/2012 02:27 PM, Simon Glass wrote: > This function is made available to board which want to display a message > when a panic() occurs before the console is set up. This would otherwise > result in a silent hang or reboot. > > Boards should call tegra_pre_console_panic() and pass the UARTs which > are available and safe for a message, as well as the selected clock and > serial multiplier values. Defaults are available as > CONFIG_DEFAULT_NS16550_CLK and CONFIG_DEFAULT_NS16550_MULT. ... > diff --git a/arch/arm/cpu/armv7/tegra2/board.c b/arch/arm/cpu/armv7/tegra2/board.c ... > +void tegra_pre_console_panic(int uart_ids, unsigned clock_freq, > + unsigned multiplier, const char *str) > +{ > + int baudrate, divisor; > + const u32 *uart_addr; > + > + /* Enable all permitted UARTs */ > + tegra_setup_uarts(uart_ids); That call honors uart_ids. ... > + /* > + * Now send the string out all the selected UARTs. We don't try all > + * possible configurations, but this could be added if required. > + */ > + baudrate = CONFIG_BAUDRATE; > + divisor = (clock_freq + (baudrate * (multiplier / 2))) / > + (multiplier * baudrate); > + > + for (uart_addr = uart_reg_addr; *uart_addr; uart_addr++) { Shouldn't this loop also honor uart_ids, and skip sending data to UARTS not in uart_ids? Sure, they aren't set up above, but perhaps they were set up elsewhere in the code and hence are capable of sending out data anyway? > + NS16550_t regs = (NS16550_t)*uart_addr; > + const char *s; > + > + NS16550_init(regs, divisor); > + for (s = str; *s; s++) { > + NS16550_putc(regs, *s); > + if (*s == '\n') > + NS16550_putc(regs, '\r'); > + } > + NS16550_putc(regs, '\n'); > + NS16550_putc(regs, '\r'); > + } > +}
Hi Stephen, On Mon, Mar 19, 2012 at 2:16 PM, Stephen Warren <swarren@wwwdotorg.org> wrote: > On 03/19/2012 02:27 PM, Simon Glass wrote: >> This function is made available to board which want to display a message >> when a panic() occurs before the console is set up. This would otherwise >> result in a silent hang or reboot. >> >> Boards should call tegra_pre_console_panic() and pass the UARTs which >> are available and safe for a message, as well as the selected clock and >> serial multiplier values. Defaults are available as >> CONFIG_DEFAULT_NS16550_CLK and CONFIG_DEFAULT_NS16550_MULT. > ... >> diff --git a/arch/arm/cpu/armv7/tegra2/board.c b/arch/arm/cpu/armv7/tegra2/board.c > ... >> +void tegra_pre_console_panic(int uart_ids, unsigned clock_freq, >> + unsigned multiplier, const char *str) >> +{ >> + int baudrate, divisor; >> + const u32 *uart_addr; >> + >> + /* Enable all permitted UARTs */ >> + tegra_setup_uarts(uart_ids); > > That call honors uart_ids. ... > >> + /* >> + * Now send the string out all the selected UARTs. We don't try all >> + * possible configurations, but this could be added if required. >> + */ >> + baudrate = CONFIG_BAUDRATE; >> + divisor = (clock_freq + (baudrate * (multiplier / 2))) / >> + (multiplier * baudrate); >> + >> + for (uart_addr = uart_reg_addr; *uart_addr; uart_addr++) { > > Shouldn't this loop also honor uart_ids, and skip sending data to UARTS > not in uart_ids? Sure, they aren't set up above, but perhaps they were > set up elsewhere in the code and hence are capable of sending out data > anyway? No, my intent was to use the same value but I overlooked it. I will fix this. > >> + NS16550_t regs = (NS16550_t)*uart_addr; >> + const char *s; >> + >> + NS16550_init(regs, divisor); >> + for (s = str; *s; s++) { >> + NS16550_putc(regs, *s); >> + if (*s == '\n') >> + NS16550_putc(regs, '\r'); >> + } >> + NS16550_putc(regs, '\n'); >> + NS16550_putc(regs, '\r'); >> + } >> +} Regards, Simon
diff --git a/arch/arm/cpu/armv7/tegra2/board.c b/arch/arm/cpu/armv7/tegra2/board.c index c9a7520..6e76dbe 100644 --- a/arch/arm/cpu/armv7/tegra2/board.c +++ b/arch/arm/cpu/armv7/tegra2/board.c @@ -22,6 +22,7 @@ */ #include <common.h> +#include <ns16550.h> #include <asm/io.h> #include "ap20.h" #include <asm/arch/board.h> @@ -137,3 +138,46 @@ void enable_caches(void) dcache_enable(); } #endif + +/* + * Possible UART locations: we ignore UARTC at 0x70006200 and UARTE at + * 0x70006400, since we don't have code to init them + */ +static const u32 uart_reg_addr[] = { + NV_PA_APB_UARTA_BASE, + NV_PA_APB_UARTB_BASE, + NV_PA_APB_UARTD_BASE, + 0 +}; + +void tegra_pre_console_panic(int uart_ids, unsigned clock_freq, + unsigned multiplier, const char *str) +{ + int baudrate, divisor; + const u32 *uart_addr; + + /* Enable all permitted UARTs */ + tegra_setup_uarts(uart_ids); + + /* + * Now send the string out all the selected UARTs. We don't try all + * possible configurations, but this could be added if required. + */ + baudrate = CONFIG_BAUDRATE; + divisor = (clock_freq + (baudrate * (multiplier / 2))) / + (multiplier * baudrate); + + for (uart_addr = uart_reg_addr; *uart_addr; uart_addr++) { + NS16550_t regs = (NS16550_t)*uart_addr; + const char *s; + + NS16550_init(regs, divisor); + for (s = str; *s; s++) { + NS16550_putc(regs, *s); + if (*s == '\n') + NS16550_putc(regs, '\r'); + } + NS16550_putc(regs, '\n'); + NS16550_putc(regs, '\r'); + } +} diff --git a/arch/arm/include/asm/arch-tegra2/board.h b/arch/arm/include/asm/arch-tegra2/board.h index fb88517..fd2489f 100644 --- a/arch/arm/include/asm/arch-tegra2/board.h +++ b/arch/arm/include/asm/arch-tegra2/board.h @@ -41,6 +41,19 @@ enum { */ void tegra_setup_uarts(int uart_ids); +/** + * Display a panic message on selected UARTs. + * + * This is called when we have no console yet but have hit a panic(). It + * is normally called from board_pre_console_panic(), which passes in the + * UARTs that we are permitted to output to. + * + * We display a message on each UART in the hope that one will reach the + * user. + */ +void tegra_pre_console_panic(int uart_ids, unsigned clock_freq, + unsigned multiplier, const char *str); + /* Setup UARTs for the board according to the selected config */ void board_init_uart_f(void); diff --git a/include/configs/tegra2-common.h b/include/configs/tegra2-common.h index 837f859..14d7602 100644 --- a/include/configs/tegra2-common.h +++ b/include/configs/tegra2-common.h @@ -84,6 +84,10 @@ #define CONFIG_SYS_BAUDRATE_TABLE {4800, 9600, 19200, 38400, 57600,\ 115200} +/* Default serial clock and multiplier */ +#define CONFIG_DEFAULT_NS16550_CLK V_NS16550_CLK +#define CONFIG_DEFAULT_NS16550_MULT 16 + /* * This parameter affects a TXFILLTUNING field that controls how much data is * sent to the latency fifo before it is sent to the wire. Without this
This function is made available to board which want to display a message when a panic() occurs before the console is set up. This would otherwise result in a silent hang or reboot. Boards should call tegra_pre_console_panic() and pass the UARTs which are available and safe for a message, as well as the selected clock and serial multiplier values. Defaults are available as CONFIG_DEFAULT_NS16550_CLK and CONFIG_DEFAULT_NS16550_MULT. Signed-off-by: Simon Glass <sjg@chromium.org> --- arch/arm/cpu/armv7/tegra2/board.c | 44 ++++++++++++++++++++++++++++++ arch/arm/include/asm/arch-tegra2/board.h | 13 +++++++++ include/configs/tegra2-common.h | 4 +++ 3 files changed, 61 insertions(+), 0 deletions(-)