Setting Config[OD] gets rid of a _LOT_ of spurious CPLD interrupts, but also decreases overall performance a bit. Signed-off-by: Manuel Lauss <manuel.lauss@xxxxxxxxxxxxxx> --- v2: improvements and fixes, thanks to Sergei Shtylyov. arch/mips/alchemy/common/setup.c | 4 ++-- arch/mips/alchemy/devboards/db1200/setup.c | 7 +++++++ 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/arch/mips/alchemy/common/setup.c b/arch/mips/alchemy/common/setup.c index 561e5da..1b887c8 100644 --- a/arch/mips/alchemy/common/setup.c +++ b/arch/mips/alchemy/common/setup.c @@ -52,8 +52,6 @@ void __init plat_mem_setup(void) /* this is faster than wasting cycles trying to approximate it */ preset_lpj = (est_freq >> 1) / HZ; - board_setup(); /* board specific setup */ - if (au1xxx_cpu_needs_config_od()) /* Various early Au1xx0 errata corrected by this */ set_c0_config(1 << 19); /* Set Config[OD] */ @@ -61,6 +59,8 @@ void __init plat_mem_setup(void) /* Clear to obtain best system bus performance */ clear_c0_config(1 << 19); /* Clear Config[OD] */ + board_setup(); /* board specific setup */ + /* IO/MEM resources. */ set_io_port_base(0); ioport_resource.start = IOPORT_RESOURCE_START; diff --git a/arch/mips/alchemy/devboards/db1200/setup.c b/arch/mips/alchemy/devboards/db1200/setup.c index 8876195..be788c8 100644 --- a/arch/mips/alchemy/devboards/db1200/setup.c +++ b/arch/mips/alchemy/devboards/db1200/setup.c @@ -23,6 +23,13 @@ void __init board_setup(void) unsigned long freq0, clksrc, div, pfc; unsigned short whoami; + /* Set Config[OD] (disable overlapping bus transaction): + * This gets rid of a _lot_ of spurious interrupts (especially + * wrt. IDE); but incurs ~10% performance hit in some + * cpu-bound applications. + */ + set_c0_config(1 << 19); + bcsr_init(DB1200_BCSR_PHYS_ADDR, DB1200_BCSR_PHYS_ADDR + DB1200_BCSR_HEXLED_OFS); -- 1.7.4
