In sprz318f.pdf "Usage Note 2.7" says that UARTs cannot acknowledge idle requests in smartidle mode when configured for DMA operations. This prevents L4 from going idle. So let's use force-idle mode instead and also force reconfiguring of the IO chain wake-up events.
Otherwise systems using Sebastian's 8250 patches with DMA will never enter deeper idle states because of the errata above. Cc: Paul Walmsley <[email protected]> Cc: Sebastian Andrzej Siewior <[email protected]> Signed-off-by: Tony Lindgren <[email protected]> --- arch/arm/mach-omap2/omap_hwmod_3xxx_data.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c index 61cd49d..55f088c 100644 --- a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c +++ b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c @@ -490,7 +490,9 @@ static struct omap_hwmod omap3xxx_uart1_hwmod = { .mpu_irqs = omap2_uart1_mpu_irqs, .sdma_reqs = omap2_uart1_sdma_reqs, .main_clk = "uart1_fck", - .flags = DEBUG_TI81XXUART1_FLAGS | HWMOD_SWSUP_SIDLE_ACT, + .flags = DEBUG_TI81XXUART1_FLAGS | + HWMOD_NO_OCP_AUTOIDLE | HWMOD_SWSUP_SIDLE | + HWMOD_FORCE_MSTANDBY | HWMOD_RECONFIG_IO_CHAIN, .prcm = { .omap2 = { .module_offs = CORE_MOD, @@ -509,7 +511,9 @@ static struct omap_hwmod omap3xxx_uart2_hwmod = { .mpu_irqs = omap2_uart2_mpu_irqs, .sdma_reqs = omap2_uart2_sdma_reqs, .main_clk = "uart2_fck", - .flags = DEBUG_TI81XXUART2_FLAGS | HWMOD_SWSUP_SIDLE_ACT, + .flags = DEBUG_TI81XXUART2_FLAGS | + HWMOD_NO_OCP_AUTOIDLE | HWMOD_SWSUP_SIDLE | + HWMOD_FORCE_MSTANDBY | HWMOD_RECONFIG_IO_CHAIN, .prcm = { .omap2 = { .module_offs = CORE_MOD, @@ -529,7 +533,8 @@ static struct omap_hwmod omap3xxx_uart3_hwmod = { .sdma_reqs = omap2_uart3_sdma_reqs, .main_clk = "uart3_fck", .flags = DEBUG_OMAP3UART3_FLAGS | DEBUG_TI81XXUART3_FLAGS | - HWMOD_SWSUP_SIDLE_ACT, + HWMOD_NO_OCP_AUTOIDLE | HWMOD_SWSUP_SIDLE | + HWMOD_FORCE_MSTANDBY | HWMOD_RECONFIG_IO_CHAIN, .prcm = { .omap2 = { .module_offs = OMAP3430_PER_MOD, @@ -559,7 +564,9 @@ static struct omap_hwmod omap36xx_uart4_hwmod = { .mpu_irqs = uart4_mpu_irqs, .sdma_reqs = uart4_sdma_reqs, .main_clk = "uart4_fck", - .flags = DEBUG_OMAP3UART4_FLAGS | HWMOD_SWSUP_SIDLE_ACT, + .flags = DEBUG_OMAP3UART4_FLAGS | + HWMOD_NO_OCP_AUTOIDLE | HWMOD_SWSUP_SIDLE | + HWMOD_FORCE_MSTANDBY | HWMOD_RECONFIG_IO_CHAIN, .prcm = { .omap2 = { .module_offs = OMAP3430_PER_MOD, -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
