diff options
Diffstat (limited to 'target/linux/ipq806x/patches/001-spi-qup-Add-DMA-capabilities.patch')
-rw-r--r-- | target/linux/ipq806x/patches/001-spi-qup-Add-DMA-capabilities.patch | 522 |
1 files changed, 522 insertions, 0 deletions
diff --git a/target/linux/ipq806x/patches/001-spi-qup-Add-DMA-capabilities.patch b/target/linux/ipq806x/patches/001-spi-qup-Add-DMA-capabilities.patch new file mode 100644 index 0000000000..62badd5387 --- /dev/null +++ b/target/linux/ipq806x/patches/001-spi-qup-Add-DMA-capabilities.patch @@ -0,0 +1,522 @@ +Content-Type: text/plain; charset="utf-8" +MIME-Version: 1.0 +Content-Transfer-Encoding: 7bit +Subject: spi: qup: Add DMA capabilities +From: Andy Gross <agross@codeaurora.org> +X-Patchwork-Id: 4432401 +Message-Id: <1403816781-31008-1-git-send-email-agross@codeaurora.org> +To: Mark Brown <broonie@kernel.org> +Cc: linux-spi@vger.kernel.org, Sagar Dharia <sdharia@codeaurora.org>, + Daniel Sneddon <dsneddon@codeaurora.org>, + Bjorn Andersson <bjorn.andersson@sonymobile.com>, + "Ivan T. Ivanov" <iivanov@mm-sol.com>, + linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, + linux-arm-msm@vger.kernel.org, Andy Gross <agross@codeaurora.org> +Date: Thu, 26 Jun 2014 16:06:21 -0500 + +This patch adds DMA capabilities to the spi-qup driver. If DMA channels are +present, the QUP will use DMA instead of block mode for transfers to/from SPI +peripherals for transactions larger than the length of a block. + +Signed-off-by: Andy Gross <agross@codeaurora.org> + +--- +.../devicetree/bindings/spi/qcom,spi-qup.txt | 10 + + drivers/spi/spi-qup.c | 361 ++++++++++++++++++-- + 2 files changed, 350 insertions(+), 21 deletions(-) + +--- a/Documentation/devicetree/bindings/spi/qcom,spi-qup.txt ++++ b/Documentation/devicetree/bindings/spi/qcom,spi-qup.txt +@@ -27,6 +27,11 @@ Optional properties: + - spi-max-frequency: Specifies maximum SPI clock frequency, + Units - Hz. Definition as per + Documentation/devicetree/bindings/spi/spi-bus.txt ++- dmas : Two DMA channel specifiers following the convention outlined ++ in bindings/dma/dma.txt ++- dma-names: Names for the dma channels, if present. There must be at ++ least one channel named "tx" for transmit and named "rx" for ++ receive. + - num-cs: total number of chipselects + - cs-gpios: should specify GPIOs used for chipselects. + The gpios will be referred to as reg = <index> in the SPI child +@@ -51,6 +56,10 @@ Example: + clocks = <&gcc GCC_BLSP2_QUP2_SPI_APPS_CLK>, <&gcc GCC_BLSP2_AHB_CLK>; + clock-names = "core", "iface"; + ++ dmas = <&blsp2_bam 2>, ++ <&blsp2_bam 3>; ++ dma-names = "rx", "tx"; ++ + pinctrl-names = "default"; + pinctrl-0 = <&spi8_default>; + +--- a/drivers/spi/spi-qup.c ++++ b/drivers/spi/spi-qup.c +@@ -22,6 +22,8 @@ + #include <linux/platform_device.h> + #include <linux/pm_runtime.h> + #include <linux/spi/spi.h> ++#include <linux/dmaengine.h> ++#include <linux/dma-mapping.h> + + #define QUP_CONFIG 0x0000 + #define QUP_STATE 0x0004 +@@ -116,6 +118,8 @@ + + #define SPI_NUM_CHIPSELECTS 4 + ++#define SPI_MAX_XFER (SZ_64K - 64) ++ + /* high speed mode is when bus rate is greater then 26MHz */ + #define SPI_HS_MIN_RATE 26000000 + #define SPI_MAX_RATE 50000000 +@@ -143,6 +147,17 @@ struct spi_qup { + int tx_bytes; + int rx_bytes; + int qup_v1; ++ ++ int use_dma; ++ ++ struct dma_chan *rx_chan; ++ struct dma_slave_config rx_conf; ++ struct dma_chan *tx_chan; ++ struct dma_slave_config tx_conf; ++ dma_addr_t rx_dma; ++ dma_addr_t tx_dma; ++ void *dummy; ++ atomic_t dma_outstanding; + }; + + +@@ -266,6 +281,221 @@ static void spi_qup_fifo_write(struct sp + } + } + ++static void qup_dma_callback(void *data) ++{ ++ struct spi_qup *controller = data; ++ ++ if (atomic_dec_and_test(&controller->dma_outstanding)) ++ complete(&controller->done); ++} ++ ++static int spi_qup_do_dma(struct spi_qup *controller, struct spi_transfer *xfer) ++{ ++ struct dma_async_tx_descriptor *rxd, *txd; ++ dma_cookie_t rx_cookie, tx_cookie; ++ u32 xfer_len, rx_align = 0, tx_align = 0, n_words; ++ struct scatterlist tx_sg[2], rx_sg[2]; ++ int ret = 0; ++ u32 bytes_to_xfer = xfer->len; ++ u32 offset = 0; ++ u32 rx_nents = 0, tx_nents = 0; ++ dma_addr_t rx_dma = 0, tx_dma = 0, rx_dummy_dma = 0, tx_dummy_dma = 0; ++ ++ ++ if (xfer->rx_buf) { ++ rx_dma = dma_map_single(controller->dev, xfer->rx_buf, ++ xfer->len, DMA_FROM_DEVICE); ++ ++ if (dma_mapping_error(controller->dev, rx_dma)) { ++ ret = -ENOMEM; ++ return ret; ++ } ++ ++ /* check to see if we need dummy buffer for leftover bytes */ ++ rx_align = xfer->len % controller->in_blk_sz; ++ if (rx_align) { ++ rx_dummy_dma = dma_map_single(controller->dev, ++ controller->dummy, controller->in_fifo_sz, ++ DMA_FROM_DEVICE); ++ ++ if (dma_mapping_error(controller->dev, rx_dummy_dma)) { ++ ret = -ENOMEM; ++ goto err_map_rx_dummy; ++ } ++ } ++ } ++ ++ if (xfer->tx_buf) { ++ tx_dma = dma_map_single(controller->dev, ++ (void *)xfer->tx_buf, xfer->len, DMA_TO_DEVICE); ++ ++ if (dma_mapping_error(controller->dev, tx_dma)) { ++ ret = -ENOMEM; ++ goto err_map_tx; ++ } ++ ++ /* check to see if we need dummy buffer for leftover bytes */ ++ tx_align = xfer->len % controller->out_blk_sz; ++ if (tx_align) { ++ memcpy(controller->dummy + SZ_1K, ++ xfer->tx_buf + xfer->len - tx_align, ++ tx_align); ++ memset(controller->dummy + SZ_1K + tx_align, 0, ++ controller->out_blk_sz - tx_align); ++ ++ tx_dummy_dma = dma_map_single(controller->dev, ++ controller->dummy + SZ_1K, ++ controller->out_blk_sz, DMA_TO_DEVICE); ++ ++ if (dma_mapping_error(controller->dev, tx_dummy_dma)) { ++ ret = -ENOMEM; ++ goto err_map_tx_dummy; ++ } ++ } ++ } ++ ++ atomic_set(&controller->dma_outstanding, 0); ++ ++ while (bytes_to_xfer > 0) { ++ xfer_len = min_t(u32, bytes_to_xfer, SPI_MAX_XFER); ++ n_words = DIV_ROUND_UP(xfer_len, controller->w_size); ++ ++ /* write out current word count to controller */ ++ writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT); ++ writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT); ++ ++ reinit_completion(&controller->done); ++ ++ if (xfer->tx_buf) { ++ /* recalc align for each transaction */ ++ tx_align = xfer_len % controller->out_blk_sz; ++ ++ if (tx_align) ++ tx_nents = 2; ++ else ++ tx_nents = 1; ++ ++ /* initialize scatterlists */ ++ sg_init_table(tx_sg, tx_nents); ++ sg_dma_len(&tx_sg[0]) = xfer_len - tx_align; ++ sg_dma_address(&tx_sg[0]) = tx_dma + offset; ++ ++ /* account for non block size transfer */ ++ if (tx_align) { ++ sg_dma_len(&tx_sg[1]) = controller->out_blk_sz; ++ sg_dma_address(&tx_sg[1]) = tx_dummy_dma; ++ } ++ ++ txd = dmaengine_prep_slave_sg(controller->tx_chan, ++ tx_sg, tx_nents, DMA_MEM_TO_DEV, 0); ++ if (!txd) { ++ ret = -ENOMEM; ++ goto err_unmap; ++ } ++ ++ atomic_inc(&controller->dma_outstanding); ++ ++ txd->callback = qup_dma_callback; ++ txd->callback_param = controller; ++ ++ tx_cookie = dmaengine_submit(txd); ++ ++ dma_async_issue_pending(controller->tx_chan); ++ } ++ ++ if (xfer->rx_buf) { ++ /* recalc align for each transaction */ ++ rx_align = xfer_len % controller->in_blk_sz; ++ ++ if (rx_align) ++ rx_nents = 2; ++ else ++ rx_nents = 1; ++ ++ /* initialize scatterlists */ ++ sg_init_table(rx_sg, rx_nents); ++ sg_dma_address(&rx_sg[0]) = rx_dma + offset; ++ sg_dma_len(&rx_sg[0]) = xfer_len - rx_align; ++ ++ /* account for non block size transfer */ ++ if (rx_align) { ++ sg_dma_len(&rx_sg[1]) = controller->in_blk_sz; ++ sg_dma_address(&rx_sg[1]) = rx_dummy_dma; ++ } ++ ++ rxd = dmaengine_prep_slave_sg(controller->rx_chan, ++ rx_sg, rx_nents, DMA_DEV_TO_MEM, 0); ++ if (!rxd) { ++ ret = -ENOMEM; ++ goto err_unmap; ++ } ++ ++ atomic_inc(&controller->dma_outstanding); ++ ++ rxd->callback = qup_dma_callback; ++ rxd->callback_param = controller; ++ ++ rx_cookie = dmaengine_submit(rxd); ++ ++ dma_async_issue_pending(controller->rx_chan); ++ } ++ ++ if (spi_qup_set_state(controller, QUP_STATE_RUN)) { ++ dev_warn(controller->dev, "cannot set EXECUTE state\n"); ++ goto err_unmap; ++ } ++ ++ if (!wait_for_completion_timeout(&controller->done, ++ msecs_to_jiffies(1000))) { ++ ret = -ETIMEDOUT; ++ ++ /* clear out all the DMA transactions */ ++ if (xfer->tx_buf) ++ dmaengine_terminate_all(controller->tx_chan); ++ if (xfer->rx_buf) ++ dmaengine_terminate_all(controller->rx_chan); ++ ++ goto err_unmap; ++ } ++ ++ if (rx_align) ++ memcpy(xfer->rx_buf + offset + xfer->len - rx_align, ++ controller->dummy, rx_align); ++ ++ /* adjust remaining bytes to transfer */ ++ bytes_to_xfer -= xfer_len; ++ offset += xfer_len; ++ ++ ++ /* reset mini-core state so we can program next transaction */ ++ if (spi_qup_set_state(controller, QUP_STATE_RESET)) { ++ dev_err(controller->dev, "cannot set RESET state\n"); ++ goto err_unmap; ++ } ++ } ++ ++ ret = 0; ++ ++err_unmap: ++ if (tx_align) ++ dma_unmap_single(controller->dev, tx_dummy_dma, ++ controller->out_fifo_sz, DMA_TO_DEVICE); ++err_map_tx_dummy: ++ if (xfer->tx_buf) ++ dma_unmap_single(controller->dev, tx_dma, xfer->len, ++ DMA_TO_DEVICE); ++err_map_tx: ++ if (rx_align) ++ dma_unmap_single(controller->dev, rx_dummy_dma, ++ controller->in_fifo_sz, DMA_FROM_DEVICE); ++err_map_rx_dummy: ++ if (xfer->rx_buf) ++ dma_unmap_single(controller->dev, rx_dma, xfer->len, ++ DMA_FROM_DEVICE); ++ ++ return ret; ++} ++ + static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id) + { + struct spi_qup *controller = dev_id; +@@ -315,11 +545,13 @@ static irqreturn_t spi_qup_qup_irq(int i + error = -EIO; + } + +- if (opflags & QUP_OP_IN_SERVICE_FLAG) +- spi_qup_fifo_read(controller, xfer); ++ if (!controller->use_dma) { ++ if (opflags & QUP_OP_IN_SERVICE_FLAG) ++ spi_qup_fifo_read(controller, xfer); + +- if (opflags & QUP_OP_OUT_SERVICE_FLAG) +- spi_qup_fifo_write(controller, xfer); ++ if (opflags & QUP_OP_OUT_SERVICE_FLAG) ++ spi_qup_fifo_write(controller, xfer); ++ } + + spin_lock_irqsave(&controller->lock, flags); + controller->error = error; +@@ -339,6 +571,8 @@ static int spi_qup_io_config(struct spi_ + struct spi_qup *controller = spi_master_get_devdata(spi->master); + u32 config, iomode, mode; + int ret, n_words, w_size; ++ size_t dma_align = dma_get_cache_alignment(); ++ u32 dma_available = 0; + + if (spi->mode & SPI_LOOP && xfer->len > controller->in_fifo_sz) { + dev_err(controller->dev, "too big size for loopback %d > %d\n", +@@ -367,6 +601,11 @@ static int spi_qup_io_config(struct spi_ + n_words = xfer->len / w_size; + controller->w_size = w_size; + ++ if (controller->rx_chan && ++ IS_ALIGNED((size_t)xfer->tx_buf, dma_align) && ++ IS_ALIGNED((size_t)xfer->rx_buf, dma_align)) ++ dma_available = 1; ++ + if (n_words <= (controller->in_fifo_sz / sizeof(u32))) { + mode = QUP_IO_M_MODE_FIFO; + writel_relaxed(n_words, controller->base + QUP_MX_READ_CNT); +@@ -374,19 +613,31 @@ static int spi_qup_io_config(struct spi_ + /* must be zero for FIFO */ + writel_relaxed(0, controller->base + QUP_MX_INPUT_CNT); + writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT); +- } else { ++ controller->use_dma = 0; ++ } else if (!dma_available) { + mode = QUP_IO_M_MODE_BLOCK; + writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT); + writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT); + /* must be zero for BLOCK and BAM */ + writel_relaxed(0, controller->base + QUP_MX_READ_CNT); + writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT); ++ controller->use_dma = 0; ++ } else { ++ mode = QUP_IO_M_MODE_DMOV; ++ writel_relaxed(0, controller->base + QUP_MX_READ_CNT); ++ writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT); ++ controller->use_dma = 1; + } + + iomode = readl_relaxed(controller->base + QUP_IO_M_MODES); + /* Set input and output transfer mode */ + iomode &= ~(QUP_IO_M_INPUT_MODE_MASK | QUP_IO_M_OUTPUT_MODE_MASK); +- iomode &= ~(QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN); ++ ++ if (!controller->use_dma) ++ iomode &= ~(QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN); ++ else ++ iomode |= QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN; ++ + iomode |= (mode << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT); + iomode |= (mode << QUP_IO_M_INPUT_MODE_MASK_SHIFT); + +@@ -419,6 +670,14 @@ static int spi_qup_io_config(struct spi_ + config &= ~(QUP_CONFIG_NO_INPUT | QUP_CONFIG_NO_OUTPUT | QUP_CONFIG_N); + config |= xfer->bits_per_word - 1; + config |= QUP_CONFIG_SPI_MODE; ++ ++ if (controller->use_dma) { ++ if (!xfer->tx_buf) ++ config |= QUP_CONFIG_NO_OUTPUT; ++ if (!xfer->rx_buf) ++ config |= QUP_CONFIG_NO_INPUT; ++ } ++ + writel_relaxed(config, controller->base + QUP_CONFIG); + + /* only write to OPERATIONAL_MASK when register is present */ +@@ -452,25 +711,29 @@ static int spi_qup_transfer_one(struct s + controller->tx_bytes = 0; + spin_unlock_irqrestore(&controller->lock, flags); + +- if (spi_qup_set_state(controller, QUP_STATE_RUN)) { +- dev_warn(controller->dev, "cannot set RUN state\n"); +- goto exit; +- } ++ if (controller->use_dma) { ++ ret = spi_qup_do_dma(controller, xfer); ++ } else { ++ if (spi_qup_set_state(controller, QUP_STATE_RUN)) { ++ dev_warn(controller->dev, "cannot set RUN state\n"); ++ goto exit; ++ } + +- if (spi_qup_set_state(controller, QUP_STATE_PAUSE)) { +- dev_warn(controller->dev, "cannot set PAUSE state\n"); +- goto exit; +- } ++ if (spi_qup_set_state(controller, QUP_STATE_PAUSE)) { ++ dev_warn(controller->dev, "cannot set PAUSE state\n"); ++ goto exit; ++ } + +- spi_qup_fifo_write(controller, xfer); ++ spi_qup_fifo_write(controller, xfer); + +- if (spi_qup_set_state(controller, QUP_STATE_RUN)) { +- dev_warn(controller->dev, "cannot set EXECUTE state\n"); +- goto exit; +- } ++ if (spi_qup_set_state(controller, QUP_STATE_RUN)) { ++ dev_warn(controller->dev, "cannot set EXECUTE state\n"); ++ goto exit; ++ } + +- if (!wait_for_completion_timeout(&controller->done, timeout)) +- ret = -ETIMEDOUT; ++ if (!wait_for_completion_timeout(&controller->done, timeout)) ++ ret = -ETIMEDOUT; ++ } + exit: + spi_qup_set_state(controller, QUP_STATE_RESET); + spin_lock_irqsave(&controller->lock, flags); +@@ -553,6 +816,7 @@ static int spi_qup_probe(struct platform + master->transfer_one = spi_qup_transfer_one; + master->dev.of_node = pdev->dev.of_node; + master->auto_runtime_pm = true; ++ master->dma_alignment = dma_get_cache_alignment(); + + platform_set_drvdata(pdev, master); + +@@ -618,6 +882,56 @@ static int spi_qup_probe(struct platform + QUP_ERROR_INPUT_UNDER_RUN | QUP_ERROR_OUTPUT_UNDER_RUN, + base + QUP_ERROR_FLAGS_EN); + ++ /* allocate dma resources, if available */ ++ controller->rx_chan = dma_request_slave_channel(&pdev->dev, "rx"); ++ if (controller->rx_chan) { ++ controller->tx_chan = ++ dma_request_slave_channel(&pdev->dev, "tx"); ++ ++ if (!controller->tx_chan) { ++ dev_err(&pdev->dev, "Failed to allocate dma tx chan"); ++ dma_release_channel(controller->rx_chan); ++ } ++ ++ /* set DMA parameters */ ++ controller->rx_conf.device_fc = 1; ++ controller->rx_conf.src_addr = res->start + QUP_INPUT_FIFO; ++ controller->rx_conf.src_maxburst = controller->in_blk_sz; ++ ++ controller->tx_conf.device_fc = 1; ++ controller->tx_conf.dst_addr = res->start + QUP_OUTPUT_FIFO; ++ controller->tx_conf.dst_maxburst = controller->out_blk_sz; ++ ++ if (dmaengine_slave_config(controller->rx_chan, ++ &controller->rx_conf)) { ++ dev_err(&pdev->dev, "failed to configure RX channel\n"); ++ ++ dma_release_channel(controller->rx_chan); ++ dma_release_channel(controller->tx_chan); ++ controller->tx_chan = NULL; ++ controller->rx_chan = NULL; ++ } else if (dmaengine_slave_config(controller->tx_chan, ++ &controller->tx_conf)) { ++ dev_err(&pdev->dev, "failed to configure TX channel\n"); ++ ++ dma_release_channel(controller->rx_chan); ++ dma_release_channel(controller->tx_chan); ++ controller->tx_chan = NULL; ++ controller->rx_chan = NULL; ++ } ++ ++ controller->dummy = devm_kmalloc(controller->dev, PAGE_SIZE, ++ GFP_KERNEL); ++ ++ if (!controller->dummy) { ++ dma_release_channel(controller->rx_chan); ++ dma_release_channel(controller->tx_chan); ++ controller->tx_chan = NULL; ++ controller->rx_chan = NULL; ++ } ++ } ++ ++ + writel_relaxed(0, base + SPI_CONFIG); + writel_relaxed(SPI_IO_C_NO_TRI_STATE, base + SPI_IO_CONTROL); + +@@ -730,6 +1044,11 @@ static int spi_qup_remove(struct platfor + if (ret) + return ret; + ++ if (controller->rx_chan) ++ dma_release_channel(controller->rx_chan); ++ if (controller->tx_chan) ++ dma_release_channel(controller->tx_chan); ++ + clk_disable_unprepare(controller->cclk); + clk_disable_unprepare(controller->iclk); + |