On 06/01/2013 09:29 AM, Olof Johansson wrote: > On Fri, May 31, 2013 at 05:19:02PM +0530, Tushar Behera wrote: >> Printing low-level debug messages make an assumption that the specified >> UART port has been preconfigured by the bootloader. Incorrectly >> specified UART port results in system getting stalled while printing the >> message "Uncompressing Linux... done, booting the kernel" >> >> This UART port number is specified through S3C_LOWLEVEL_UART_PORT. Since >> the UART port might different for different board, it is not possible to >> specify it correctly for every board that use a common defconfig file. >> >> Calling this print subroutine only when DEBUG_LL fixes the problem. By >> disabling DEBUG_LL in default config file, we would be able to boot >> multiple boards with different default UART ports. >> >> With this current approach, we miss the print "Uncompressing Linux... >> done, booting the kernel." when DEBUG_LL is not defined. >> >> Signed-off-by: Tushar Behera <tushar.behera@xxxxxxxxxx> >> --- >> arch/arm/mach-exynos/include/mach/uncompress.h | 11 ++++++++--- >> arch/arm/plat-samsung/include/plat/uncompress.h | 10 +++++++++- >> 2 files changed, 17 insertions(+), 4 deletions(-) >> >> diff --git a/arch/arm/mach-exynos/include/mach/uncompress.h b/arch/arm/mach-exynos/include/mach/uncompress.h >> index 2979995..730f69f 100644 >> --- a/arch/arm/mach-exynos/include/mach/uncompress.h >> +++ b/arch/arm/mach-exynos/include/mach/uncompress.h >> @@ -37,11 +37,16 @@ static void arch_detect_cpu(void) >> chip_id >>= 20; >> chip_id &= 0xf; >> >> +#ifdef CONFIG_DEBUG_LL >> if (chip_id == 0x5) >> - uart_base = (volatile u8 *)EXYNOS5_PA_UART + (S3C_UART_OFFSET * CONFIG_S3C_LOWLEVEL_UART_PORT); >> + uart_base = (volatile u8 *)EXYNOS5_PA_UART + >> + (S3C_UART_OFFSET * CONFIG_S3C_LOWLEVEL_UART_PORT); >> else >> - uart_base = (volatile u8 *)EXYNOS4_PA_UART + (S3C_UART_OFFSET * CONFIG_S3C_LOWLEVEL_UART_PORT); >> - >> + uart_base = (volatile u8 *)EXYNOS4_PA_UART + >> + (S3C_UART_OFFSET * CONFIG_S3C_LOWLEVEL_UART_PORT); >> +#else >> + uart_base = NULL; >> +#endif > > You can do: > > if (!config_enabled(CONFIG_DEBUG_LL)) > return; > Thanks for the hint. Or rather, we calculate uart_base unconditionally in mach/uncompress.h and replace check for uart_base with config_enabled(CONFIG_DEBUG_LL) in plat/uncompress.h. That would get rid of all the ifdef's in the mach/uncompress.h files. Let me spin out another version with this change. > Since uart_base will be set to 0 by being in BSS anyway. > > > -Olof > -- Tushar Behera -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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