diff options
Diffstat (limited to 'target/linux/ipq806x/patches-3.18/002-v3-spi-qup-Fix-incorrect-block-transfers.patch')
| -rw-r--r-- | target/linux/ipq806x/patches-3.18/002-v3-spi-qup-Fix-incorrect-block-transfers.patch | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/target/linux/ipq806x/patches-3.18/002-v3-spi-qup-Fix-incorrect-block-transfers.patch b/target/linux/ipq806x/patches-3.18/002-v3-spi-qup-Fix-incorrect-block-transfers.patch new file mode 100644 index 0000000..62ee5b4 --- /dev/null +++ b/target/linux/ipq806x/patches-3.18/002-v3-spi-qup-Fix-incorrect-block-transfers.patch @@ -0,0 +1,376 @@ +Content-Type: text/plain; charset="utf-8" +MIME-Version: 1.0 +Content-Transfer-Encoding: 7bit +Subject: [v3] spi: qup: Fix incorrect block transfers +From: Andy Gross <agross@codeaurora.org> +X-Patchwork-Id: 5007321 +Message-Id: <1412112088-25928-1-git-send-email-agross@codeaurora.org> +To: Mark Brown <broonie@kernel.org> +Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, + linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, + "Ivan T. Ivanov" <iivanov@mm-sol.com>, + Bjorn Andersson <bjorn.andersson@sonymobile.com>, + Kumar Gala <galak@codeaurora.org>, Andy Gross <agross@codeaurora.org> +Date: Tue, 30 Sep 2014 16:21:28 -0500 + +This patch fixes a number of errors with the QUP block transfer mode. Errors +manifested themselves as input underruns, output overruns, and timed out +transactions. + +The block mode does not require the priming that occurs in FIFO mode. At the +moment that the QUP is placed into the RUN state, the QUP will immediately raise +an interrupt if the request is a write. Therefore, there is no need to prime +the pump. + +In addition, the block transfers require that whole blocks of data are +read/written at a time. The last block of data that completes a transaction may +contain less than a full blocks worth of data. + +Each block of data results in an input/output service interrupt accompanied with +a input/output block flag set. Additional block reads/writes require clearing +of the service flag. It is ok to check for additional blocks of data in the +ISR, but you have to ack every block you transfer. Imbalanced acks result in +early return from complete transactions with pending interrupts that still have +to be ack'd. The next transaction can be affected by these interrupts. +Transactions are deemed complete when the MAX_INPUT or MAX_OUTPUT flag are set. + +Changes from v2: +- Added in additional completion check so that transaction done is not + prematurely signaled. +- Fixed various review comments. + +Changes from v1: +- Split out read/write block function. +- Removed extraneous checks for transfer length + +Signed-off-by: Andy Gross <agross@codeaurora.org> + +--- +drivers/spi/spi-qup.c | 201 ++++++++++++++++++++++++++++++++++++------------- + 1 file changed, 148 insertions(+), 53 deletions(-) + +--- a/drivers/spi/spi-qup.c ++++ b/drivers/spi/spi-qup.c +@@ -82,6 +82,8 @@ + #define QUP_IO_M_MODE_BAM 3 + + /* QUP_OPERATIONAL fields */ ++#define QUP_OP_IN_BLOCK_READ_REQ BIT(13) ++#define QUP_OP_OUT_BLOCK_WRITE_REQ BIT(12) + #define QUP_OP_MAX_INPUT_DONE_FLAG BIT(11) + #define QUP_OP_MAX_OUTPUT_DONE_FLAG BIT(10) + #define QUP_OP_IN_SERVICE_FLAG BIT(9) +@@ -147,6 +149,7 @@ struct spi_qup { + int tx_bytes; + int rx_bytes; + int qup_v1; ++ int mode; + + int use_dma; + +@@ -213,30 +216,14 @@ static int spi_qup_set_state(struct spi_ + return 0; + } + +- +-static void spi_qup_fifo_read(struct spi_qup *controller, +- struct spi_transfer *xfer) ++static void spi_qup_fill_read_buffer(struct spi_qup *controller, ++ struct spi_transfer *xfer, u32 data) + { + u8 *rx_buf = xfer->rx_buf; +- u32 word, state; +- int idx, shift, w_size; +- +- w_size = controller->w_size; +- +- while (controller->rx_bytes < xfer->len) { +- +- state = readl_relaxed(controller->base + QUP_OPERATIONAL); +- if (0 == (state & QUP_OP_IN_FIFO_NOT_EMPTY)) +- break; +- +- word = readl_relaxed(controller->base + QUP_INPUT_FIFO); +- +- if (!rx_buf) { +- controller->rx_bytes += w_size; +- continue; +- } ++ int idx, shift; + +- for (idx = 0; idx < w_size; idx++, controller->rx_bytes++) { ++ if (rx_buf) ++ for (idx = 0; idx < controller->w_size; idx++) { + /* + * The data format depends on bytes per SPI word: + * 4 bytes: 0x12345678 +@@ -244,41 +231,139 @@ static void spi_qup_fifo_read(struct spi + * 1 byte : 0x00000012 + */ + shift = BITS_PER_BYTE; +- shift *= (w_size - idx - 1); +- rx_buf[controller->rx_bytes] = word >> shift; ++ shift *= (controller->w_size - idx - 1); ++ rx_buf[controller->rx_bytes + idx] = data >> shift; ++ } ++ ++ controller->rx_bytes += controller->w_size; ++} ++ ++static void spi_qup_prepare_write_data(struct spi_qup *controller, ++ struct spi_transfer *xfer, u32 *data) ++{ ++ const u8 *tx_buf = xfer->tx_buf; ++ u32 val; ++ int idx; ++ ++ *data = 0; ++ ++ if (tx_buf) ++ for (idx = 0; idx < controller->w_size; idx++) { ++ val = tx_buf[controller->tx_bytes + idx]; ++ *data |= val << (BITS_PER_BYTE * (3 - idx)); + } ++ ++ controller->tx_bytes += controller->w_size; ++} ++ ++static void spi_qup_fifo_read(struct spi_qup *controller, ++ struct spi_transfer *xfer) ++{ ++ u32 data; ++ ++ /* clear service request */ ++ writel_relaxed(QUP_OP_IN_SERVICE_FLAG, ++ controller->base + QUP_OPERATIONAL); ++ ++ while (controller->rx_bytes < xfer->len) { ++ if (!(readl_relaxed(controller->base + QUP_OPERATIONAL) & ++ QUP_OP_IN_FIFO_NOT_EMPTY)) ++ break; ++ ++ data = readl_relaxed(controller->base + QUP_INPUT_FIFO); ++ ++ spi_qup_fill_read_buffer(controller, xfer, data); + } + } + + static void spi_qup_fifo_write(struct spi_qup *controller, +- struct spi_transfer *xfer) ++ struct spi_transfer *xfer) + { +- const u8 *tx_buf = xfer->tx_buf; +- u32 word, state, data; +- int idx, w_size; ++ u32 data; + +- w_size = controller->w_size; ++ /* clear service request */ ++ writel_relaxed(QUP_OP_OUT_SERVICE_FLAG, ++ controller->base + QUP_OPERATIONAL); + + while (controller->tx_bytes < xfer->len) { + +- state = readl_relaxed(controller->base + QUP_OPERATIONAL); +- if (state & QUP_OP_OUT_FIFO_FULL) ++ if (readl_relaxed(controller->base + QUP_OPERATIONAL) & ++ QUP_OP_OUT_FIFO_FULL) + break; + +- word = 0; +- for (idx = 0; idx < w_size; idx++, controller->tx_bytes++) { ++ spi_qup_prepare_write_data(controller, xfer, &data); ++ writel_relaxed(data, controller->base + QUP_OUTPUT_FIFO); + +- if (!tx_buf) { +- controller->tx_bytes += w_size; +- break; +- } ++ } ++} + +- data = tx_buf[controller->tx_bytes]; +- word |= data << (BITS_PER_BYTE * (3 - idx)); +- } ++static void spi_qup_block_read(struct spi_qup *controller, ++ struct spi_transfer *xfer) ++{ ++ u32 data; ++ u32 reads_per_blk = controller->in_blk_sz >> 2; ++ u32 num_words = (xfer->len - controller->rx_bytes) / controller->w_size; ++ int i; ++ ++ do { ++ /* ACK by clearing service flag */ ++ writel_relaxed(QUP_OP_IN_SERVICE_FLAG, ++ controller->base + QUP_OPERATIONAL); ++ ++ /* transfer up to a block size of data in a single pass */ ++ for (i = 0; num_words && i < reads_per_blk; i++, num_words--) { ++ ++ /* read data and fill up rx buffer */ ++ data = readl_relaxed(controller->base + QUP_INPUT_FIFO); ++ spi_qup_fill_read_buffer(controller, xfer, data); ++ } ++ ++ /* check to see if next block is ready */ ++ if (!(readl_relaxed(controller->base + QUP_OPERATIONAL) & ++ QUP_OP_IN_BLOCK_READ_REQ)) ++ break; + +- writel_relaxed(word, controller->base + QUP_OUTPUT_FIFO); +- } ++ } while (num_words); ++ ++ /* ++ * Due to extra stickiness of the QUP_OP_IN_SERVICE_FLAG during block ++ * reads, it has to be cleared again at the very end ++ */ ++ if (readl_relaxed(controller->base + QUP_OPERATIONAL) & ++ QUP_OP_MAX_INPUT_DONE_FLAG) ++ writel_relaxed(QUP_OP_IN_SERVICE_FLAG, ++ controller->base + QUP_OPERATIONAL); ++ ++} ++ ++static void spi_qup_block_write(struct spi_qup *controller, ++ struct spi_transfer *xfer) ++{ ++ u32 data; ++ u32 writes_per_blk = controller->out_blk_sz >> 2; ++ u32 num_words = (xfer->len - controller->tx_bytes) / controller->w_size; ++ int i; ++ ++ do { ++ /* ACK by clearing service flag */ ++ writel_relaxed(QUP_OP_OUT_SERVICE_FLAG, ++ controller->base + QUP_OPERATIONAL); ++ ++ /* transfer up to a block size of data in a single pass */ ++ for (i = 0; num_words && i < writes_per_blk; i++, num_words--) { ++ ++ /* swizzle the bytes for output and write out */ ++ spi_qup_prepare_write_data(controller, xfer, &data); ++ writel_relaxed(data, ++ controller->base + QUP_OUTPUT_FIFO); ++ } ++ ++ /* check to see if next block is ready */ ++ if (!(readl_relaxed(controller->base + QUP_OPERATIONAL) & ++ QUP_OP_OUT_BLOCK_WRITE_REQ)) ++ break; ++ ++ } while (num_words); + } + + static void qup_dma_callback(void *data) +@@ -515,9 +600,9 @@ static irqreturn_t spi_qup_qup_irq(int i + + writel_relaxed(qup_err, controller->base + QUP_ERROR_FLAGS); + writel_relaxed(spi_err, controller->base + SPI_ERROR_FLAGS); +- writel_relaxed(opflags, controller->base + QUP_OPERATIONAL); + + if (!xfer) { ++ writel_relaxed(opflags, controller->base + QUP_OPERATIONAL); + dev_err_ratelimited(controller->dev, "unexpected irq %08x %08x %08x\n", + qup_err, spi_err, opflags); + return IRQ_HANDLED; +@@ -546,11 +631,19 @@ static irqreturn_t spi_qup_qup_irq(int i + } + + if (!controller->use_dma) { +- if (opflags & QUP_OP_IN_SERVICE_FLAG) +- spi_qup_fifo_read(controller, xfer); ++ if (opflags & QUP_OP_IN_SERVICE_FLAG) { ++ if (opflags & QUP_OP_IN_BLOCK_READ_REQ) ++ spi_qup_block_read(controller, xfer); ++ else ++ 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) { ++ if (opflags & QUP_OP_OUT_BLOCK_WRITE_REQ) ++ spi_qup_block_write(controller, xfer); ++ else ++ spi_qup_fifo_write(controller, xfer); ++ } + } + + spin_lock_irqsave(&controller->lock, flags); +@@ -558,7 +651,8 @@ static irqreturn_t spi_qup_qup_irq(int i + controller->xfer = xfer; + spin_unlock_irqrestore(&controller->lock, flags); + +- if (controller->rx_bytes == xfer->len || error) ++ if ((controller->rx_bytes == xfer->len && ++ (opflags & QUP_OP_MAX_INPUT_DONE_FLAG)) || error) + complete(&controller->done); + + return IRQ_HANDLED; +@@ -569,7 +663,7 @@ static irqreturn_t spi_qup_qup_irq(int i + static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer) + { + struct spi_qup *controller = spi_master_get_devdata(spi->master); +- u32 config, iomode, mode; ++ u32 config, iomode; + int ret, n_words, w_size; + size_t dma_align = dma_get_cache_alignment(); + u32 dma_available = 0; +@@ -607,7 +701,7 @@ static int spi_qup_io_config(struct spi_ + dma_available = 1; + + if (n_words <= (controller->in_fifo_sz / sizeof(u32))) { +- mode = QUP_IO_M_MODE_FIFO; ++ controller->mode = QUP_IO_M_MODE_FIFO; + writel_relaxed(n_words, controller->base + QUP_MX_READ_CNT); + writel_relaxed(n_words, controller->base + QUP_MX_WRITE_CNT); + /* must be zero for FIFO */ +@@ -615,7 +709,7 @@ static int spi_qup_io_config(struct spi_ + writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT); + controller->use_dma = 0; + } else if (!dma_available) { +- mode = QUP_IO_M_MODE_BLOCK; ++ controller->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 */ +@@ -623,7 +717,7 @@ static int spi_qup_io_config(struct spi_ + writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT); + controller->use_dma = 0; + } else { +- mode = QUP_IO_M_MODE_DMOV; ++ controller->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; +@@ -638,8 +732,8 @@ static int spi_qup_io_config(struct spi_ + 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); ++ iomode |= (controller->mode << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT); ++ iomode |= (controller->mode << QUP_IO_M_INPUT_MODE_MASK_SHIFT); + + writel_relaxed(iomode, controller->base + QUP_IO_M_MODES); + +@@ -724,7 +818,8 @@ static int spi_qup_transfer_one(struct s + goto exit; + } + +- spi_qup_fifo_write(controller, xfer); ++ if (controller->mode == QUP_IO_M_MODE_FIFO) ++ spi_qup_fifo_write(controller, xfer); + + if (spi_qup_set_state(controller, QUP_STATE_RUN)) { + dev_warn(controller->dev, "cannot set EXECUTE state\n"); +@@ -741,6 +836,7 @@ exit: + if (!ret) + ret = controller->error; + spin_unlock_irqrestore(&controller->lock, flags); ++ + return ret; + } + |