On Mon, Jul 06, 2009 at 12:02:56PM -0700, David Daney wrote:
> The Cavium Octeon bootloader has a debugger stub that requires a
> little help from the target application to break in.
>
> If configured, when we get an interrupt on the debug uart we wake up
> the debugger.
>
> Changes from v1: Inline octeon_get_boot_debug_flag so it compiles
> without CONFIG_CAVIUM_GDB.
>
> Signed-off-by: David Daney <ddaney@xxxxxxxxxxxxxxxxxx>
> ---
> arch/mips/Kconfig.debug | 10 ++++++
> arch/mips/cavium-octeon/serial.c | 53 ++++++++++++++++++++++++++++++++-
> arch/mips/cavium-octeon/setup.c | 2 +-
> arch/mips/include/asm/octeon/octeon.h | 1 -
> 4 files changed, 63 insertions(+), 3 deletions(-)
>
> diff --git a/arch/mips/Kconfig.debug b/arch/mips/Kconfig.debug
> index 364ca89..f6a0e68 100644
> --- a/arch/mips/Kconfig.debug
> +++ b/arch/mips/Kconfig.debug
> @@ -42,6 +42,16 @@ config SB1XXX_CORELIS
> Select compile flags that produce code that can be processed by the
> Corelis mksym utility and UDB Emulator.
>
> +config CAVIUM_GDB
> + bool "Remote GDB debugging using the Cavium Networks Multicore GDB"
> + depends on DEBUG_KERNEL
> + depends on CPU_CAVIUM_OCTEON
> + select DEBUG_INFO
> + help
> + If you say Y here, it will be possible to remotely debug the MIPS
> + kernel using the Cavium Networks GDB with extended SMP support.
> + This is only useful for kernel hackers. If unsure, say N.
> +
> config RUNTIME_DEBUG
> bool "Enable run-time debugging"
> depends on DEBUG_KERNEL
> diff --git a/arch/mips/cavium-octeon/serial.c b/arch/mips/cavium-octeon/serial.c
> index 8240728..2110e68 100644
> --- a/arch/mips/cavium-octeon/serial.c
> +++ b/arch/mips/cavium-octeon/serial.c
> @@ -18,11 +18,60 @@
>
> #include <asm/octeon/octeon.h>
>
> +#if defined(CONFIG_CAVIUM_GDB)
> +
> #ifdef CONFIG_GDB_CONSOLE
> #define DEBUG_UART 0
> #else
> #define DEBUG_UART 1
> #endif
> +static irqreturn_t interrupt_debug_char(int cpl, void *dev_id)
> +{
> + unsigned long lsrval;
> + unsigned long tmp;
> +
> + lsrval = cvmx_read_csr(CVMX_MIO_UARTX_LSR(DEBUG_UART));
> + if (lsrval & 1) {
> +#ifdef CONFIG_KGDB
> + /*
> + * The Cavium EJTAG bootmonitor stub is not compatible
> + * with KGDB. We should never get here.
> + */
> +#error Illegal to use both CONFIG_KGDB and CONFIG_CAVIUM_GDB
> +#endif
#error is only acceptable to catch bugs in Kconfig or the code itself. This
#error however is triggering on .config settings including such generated by
randconfig which is a PITA. So rather please ensure forbidden .configs
can't be generated. Alternatively, implement things such that both
config options can co-exist.
Ralf
