From: Tony Lindgren <tony@atomide.com>
Date: Thu, 18 Sep 2014 15:58:49 +0000 (-0700)
Subject: ARM: OMAP3: Use manual idle for UARTs because of DMA errata
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=a2fc36613ac1af2e92cbed7af80bc72d8114dd50;p=deliverable%2Flinux.git

ARM: OMAP3: Use manual idle for UARTs because of DMA errata

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 manual idle mode
instead.

Otherwise systems using Sebastian's 8250 patches with DMA will
never enter deeper idle states because of the errata above.

Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
---

diff --git a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
index 61cd49d26f6d..2a78b093c0ce 100644
--- a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
@@ -490,7 +490,7 @@ 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_SWSUP_SIDLE,
 	.prcm		= {
 		.omap2 = {
 			.module_offs = CORE_MOD,
@@ -509,7 +509,7 @@ 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_SWSUP_SIDLE,
 	.prcm		= {
 		.omap2 = {
 			.module_offs = CORE_MOD,
@@ -529,7 +529,7 @@ 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_SWSUP_SIDLE,
 	.prcm		= {
 		.omap2 = {
 			.module_offs = OMAP3430_PER_MOD,
@@ -559,7 +559,7 @@ 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_SWSUP_SIDLE,
 	.prcm		= {
 		.omap2 = {
 			.module_offs = OMAP3430_PER_MOD,