From c16d51a32bbb61ac8fd96f78b5ce2fccfe0fb4c3 Mon Sep 17 00:00:00 2001 From: Shreshtha Kumar Sahu Date: Mon, 13 Jun 2011 10:11:33 +0200 Subject: amba pl011: workaround for uart registers lockup This workaround aims to break the deadlock situation which raises during continuous transfer of data for long duration over uart with hardware flow control. It is observed that CTS interrupt cannot be cleared in uart interrupt register (ICR). Hence further transfer over uart gets blocked. It is seen that during such deadlock condition ICR don't get cleared even on multiple write. This leads pass_counter to decrease and finally reach zero. This can be taken as trigger point to run this UART_BT_WA. Workaround backups the register configuration, does soft reset of UART using BIT-0 of PRCC_K_SOFTRST_SET/CLEAR registers and restores the registers. This patch also provides support for uart init and exit function calls if present. Signed-off-by: Shreshtha Kumar Sahu Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman --- include/linux/amba/serial.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/amba') diff --git a/include/linux/amba/serial.h b/include/linux/amba/serial.h index 5479fdc849e9..514ed45c462e 100644 --- a/include/linux/amba/serial.h +++ b/include/linux/amba/serial.h @@ -201,6 +201,9 @@ struct amba_pl011_data { bool (*dma_filter)(struct dma_chan *chan, void *filter_param); void *dma_rx_param; void *dma_tx_param; + void (*init) (void); + void (*exit) (void); + void (*reset) (void); }; #endif -- cgit v1.2.3 From b207b4d02beb06059478339bbe4672ba715605d6 Mon Sep 17 00:00:00 2001 From: Russell King - ARM Linux Date: Thu, 21 Jul 2011 17:12:27 +0100 Subject: DMA: PL08x: separately store source/destination slave address Store the source/destination slave address separately into the channel structure. This moves us towards being able to avoid a configuration call each time we use the channel. Acked-by: Linus Walleij Signed-off-by: Russell King Signed-off-by: Vinod Koul --- include/linux/amba/pl08x.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/linux/amba') diff --git a/include/linux/amba/pl08x.h b/include/linux/amba/pl08x.h index 3111385b8ca7..072ab28bbb57 100644 --- a/include/linux/amba/pl08x.h +++ b/include/linux/amba/pl08x.h @@ -173,7 +173,8 @@ struct pl08x_dma_chan { struct tasklet_struct tasklet; char *name; struct pl08x_channel_data *cd; - dma_addr_t runtime_addr; + dma_addr_t src_addr; + dma_addr_t dst_addr; enum dma_data_direction runtime_direction; dma_cookie_t lc; struct list_head pend_list; -- cgit v1.2.3 From f14c426c723634d223344ad820997d92a3e355b6 Mon Sep 17 00:00:00 2001 From: Russell King - ARM Linux Date: Thu, 21 Jul 2011 17:12:47 +0100 Subject: DMA: PL08x: separately store source/destination cctl Store the source/destination cctl values into the channel structure. This moves us towards being able to avoid a configuration call each time we use the channel. Acked-by: Linus Walleij Signed-off-by: Russell King Signed-off-by: Vinod Koul --- include/linux/amba/pl08x.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/amba') diff --git a/include/linux/amba/pl08x.h b/include/linux/amba/pl08x.h index 072ab28bbb57..47cfe31e5c35 100644 --- a/include/linux/amba/pl08x.h +++ b/include/linux/amba/pl08x.h @@ -175,6 +175,8 @@ struct pl08x_dma_chan { struct pl08x_channel_data *cd; dma_addr_t src_addr; dma_addr_t dst_addr; + u32 src_cctl; + u32 dst_cctl; enum dma_data_direction runtime_direction; dma_cookie_t lc; struct list_head pend_list; -- cgit v1.2.3 From fa020e7d046436cb6642b23dc95012a3064d77e2 Mon Sep 17 00:00:00 2001 From: Russell King - ARM Linux Date: Thu, 21 Jul 2011 17:13:07 +0100 Subject: DMA: PL08x: constify plchan->cd and plat->slave_channels We no longer write to the channel data structure, so we can make it const throughout the driver. Acked-by: Linus Walleij Signed-off-by: Russell King Signed-off-by: Vinod Koul --- include/linux/amba/pl08x.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/amba') diff --git a/include/linux/amba/pl08x.h b/include/linux/amba/pl08x.h index 47cfe31e5c35..e6e28f37d8ec 100644 --- a/include/linux/amba/pl08x.h +++ b/include/linux/amba/pl08x.h @@ -172,7 +172,7 @@ struct pl08x_dma_chan { int phychan_hold; struct tasklet_struct tasklet; char *name; - struct pl08x_channel_data *cd; + const struct pl08x_channel_data *cd; dma_addr_t src_addr; dma_addr_t dst_addr; u32 src_cctl; @@ -205,7 +205,7 @@ struct pl08x_dma_chan { * @mem_buses: buses which memory can be accessed from: PL08X_AHB1 | PL08X_AHB2 */ struct pl08x_platform_data { - struct pl08x_channel_data *slave_channels; + const struct pl08x_channel_data *slave_channels; unsigned int num_slave_channels; struct pl08x_channel_data memcpy_channel; int (*get_signal)(struct pl08x_dma_chan *); -- cgit v1.2.3