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Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0167-bcm2835-sdhost-Only-claim-one-DMA-channel.patch')
-rw-r--r--target/linux/brcm2708/patches-4.4/0167-bcm2835-sdhost-Only-claim-one-DMA-channel.patch160
1 files changed, 0 insertions, 160 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0167-bcm2835-sdhost-Only-claim-one-DMA-channel.patch b/target/linux/brcm2708/patches-4.4/0167-bcm2835-sdhost-Only-claim-one-DMA-channel.patch
deleted file mode 100644
index 945c972431..0000000000
--- a/target/linux/brcm2708/patches-4.4/0167-bcm2835-sdhost-Only-claim-one-DMA-channel.patch
+++ /dev/null
@@ -1,160 +0,0 @@
-From 99864da2b792c10fb95f8c4f56c0a1be376a7f0d Mon Sep 17 00:00:00 2001
-From: Phil Elwell <phil@raspberrypi.org>
-Date: Mon, 7 Mar 2016 16:46:39 +0000
-Subject: [PATCH] bcm2835-sdhost: Only claim one DMA channel
-
-With both MMC controllers enabled there are few DMA channels left. The
-bcm2835-sdhost driver only uses DMA in one direction at a time, so it
-doesn't need to claim two channels.
-
-See: https://github.com/raspberrypi/linux/issues/1327
-
-Signed-off-by: Phil Elwell <phil@raspberrypi.org>
----
- arch/arm/boot/dts/bcm2708_common.dtsi | 5 +--
- drivers/mmc/host/bcm2835-sdhost.c | 70 ++++++++++++++++++++++++-----------
- 2 files changed, 50 insertions(+), 25 deletions(-)
-
---- a/arch/arm/boot/dts/bcm2708_common.dtsi
-+++ b/arch/arm/boot/dts/bcm2708_common.dtsi
-@@ -136,9 +136,8 @@
- reg = <0x7e202000 0x100>;
- interrupts = <2 24>;
- clocks = <&clk_core>;
-- dmas = <&dma 13>,
-- <&dma 13>;
-- dma-names = "tx", "rx";
-+ dmas = <&dma 13>;
-+ dma-names = "rx-tx";
- brcm,overclock-50 = <0>;
- brcm,pio-limit = <1>;
- status = "disabled";
---- a/drivers/mmc/host/bcm2835-sdhost.c
-+++ b/drivers/mmc/host/bcm2835-sdhost.c
-@@ -185,9 +185,10 @@ struct bcm2835_host {
- unsigned int debug:1; /* Enable debug output */
-
- /*DMA part*/
-- struct dma_chan *dma_chan_rx; /* DMA channel for reads */
-- struct dma_chan *dma_chan_tx; /* DMA channel for writes */
-- struct dma_chan *dma_chan; /* Channel in used */
-+ struct dma_chan *dma_chan_rxtx; /* DMA channel for reads and writes */
-+ struct dma_chan *dma_chan; /* Channel in use */
-+ struct dma_slave_config dma_cfg_rx;
-+ struct dma_slave_config dma_cfg_tx;
- struct dma_async_tx_descriptor *dma_desc;
- u32 dma_dir;
- u32 drain_words;
-@@ -771,12 +772,11 @@ static void bcm2835_sdhost_prepare_dma(s
- log_event("PRD<", (u32)data, 0);
- pr_debug("bcm2835_sdhost_prepare_dma()\n");
-
-+ dma_chan = host->dma_chan_rxtx;
- if (data->flags & MMC_DATA_READ) {
-- dma_chan = host->dma_chan_rx;
- dir_data = DMA_FROM_DEVICE;
- dir_slave = DMA_DEV_TO_MEM;
- } else {
-- dma_chan = host->dma_chan_tx;
- dir_data = DMA_TO_DEVICE;
- dir_slave = DMA_MEM_TO_DEV;
- }
-@@ -813,6 +813,12 @@ static void bcm2835_sdhost_prepare_dma(s
- host->drain_words = len/4;
- }
-
-+ /* The parameters have already been validated, so this will not fail */
-+ (void)dmaengine_slave_config(dma_chan,
-+ (dir_data == DMA_FROM_DEVICE) ?
-+ &host->dma_cfg_rx :
-+ &host->dma_cfg_tx);
-+
- len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len,
- dir_data);
-
-@@ -1805,28 +1811,46 @@ int bcm2835_sdhost_add_host(struct bcm28
- spin_lock_init(&host->lock);
-
- if (host->allow_dma) {
-- if (IS_ERR_OR_NULL(host->dma_chan_tx) ||
-- IS_ERR_OR_NULL(host->dma_chan_rx)) {
-- pr_err("%s: unable to initialise DMA channels. "
-+ if (IS_ERR_OR_NULL(host->dma_chan_rxtx)) {
-+ pr_err("%s: unable to initialise DMA channel. "
- "Falling back to PIO\n",
- mmc_hostname(mmc));
- host->use_dma = false;
- } else {
-- host->use_dma = true;
--
- cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
- cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
- cfg.slave_id = 13; /* DREQ channel */
-
-+ /* Validate the slave configurations */
-+
- cfg.direction = DMA_MEM_TO_DEV;
- cfg.src_addr = 0;
- cfg.dst_addr = host->bus_addr + SDDATA;
-- ret = dmaengine_slave_config(host->dma_chan_tx, &cfg);
-
-- cfg.direction = DMA_DEV_TO_MEM;
-- cfg.src_addr = host->bus_addr + SDDATA;
-- cfg.dst_addr = 0;
-- ret = dmaengine_slave_config(host->dma_chan_rx, &cfg);
-+ ret = dmaengine_slave_config(host->dma_chan_rxtx, &cfg);
-+
-+ if (ret == 0) {
-+ host->dma_cfg_tx = cfg;
-+
-+ cfg.direction = DMA_DEV_TO_MEM;
-+ cfg.src_addr = host->bus_addr + SDDATA;
-+ cfg.dst_addr = 0;
-+
-+ ret = dmaengine_slave_config(host->dma_chan_rxtx, &cfg);
-+ }
-+
-+ if (ret == 0) {
-+ host->dma_cfg_rx = cfg;
-+
-+ host->use_dma = true;
-+ } else {
-+ pr_err("%s: unable to configure DMA channel. "
-+ "Falling back to PIO\n",
-+ mmc_hostname(mmc));
-+ dma_release_channel(host->dma_chan_rxtx);
-+ host->dma_chan_rxtx = NULL;
-+ host->use_dma = false;
-+ }
- }
- } else {
- host->use_dma = false;
-@@ -1948,19 +1972,21 @@ static int bcm2835_sdhost_probe(struct p
-
- if (host->allow_dma) {
- if (node) {
-- host->dma_chan_tx =
-- dma_request_slave_channel(dev, "tx");
-- host->dma_chan_rx =
-- dma_request_slave_channel(dev, "rx");
-+ host->dma_chan_rxtx =
-+ dma_request_slave_channel(dev, "rx-tx");
-+ if (!host->dma_chan_rxtx)
-+ host->dma_chan_rxtx =
-+ dma_request_slave_channel(dev, "tx");
-+ if (!host->dma_chan_rxtx)
-+ host->dma_chan_rxtx =
-+ dma_request_slave_channel(dev, "rx");
- } else {
- dma_cap_mask_t mask;
-
- dma_cap_zero(mask);
- /* we don't care about the channel, any would work */
- dma_cap_set(DMA_SLAVE, mask);
-- host->dma_chan_tx =
-- dma_request_channel(mask, NULL, NULL);
-- host->dma_chan_rx =
-+ host->dma_chan_rxtx =
- dma_request_channel(mask, NULL, NULL);
- }
- }