From 549858ce76e31d5e2139e5588df976ee42607a0d Mon Sep 17 00:00:00 2001 From: Andrew Bresticker Date: Mon, 22 Dec 2014 11:35:16 -0800 Subject: [PATCH] spi: img-spfi: Select FIFO based on transfer length Since the 32-bit FIFO is deeper (64 bytes) than the 8-bit FIFO (16 bytes), use the 32-bit FIFO when there are at least 32 bits remaining to be transferred in PIO mode or when the transfer length is 32-bit aligned in DMA mode. Signed-off-by: Andrew Bresticker Signed-off-by: Mark Brown --- drivers/spi/spi-img-spfi.c | 49 ++++++++++++++++++---------------------------- 1 file changed, 19 insertions(+), 30 deletions(-) diff --git a/drivers/spi/spi-img-spfi.c b/drivers/spi/spi-img-spfi.c index aad6683..c01567d 100644 --- a/drivers/spi/spi-img-spfi.c +++ b/drivers/spi/spi-img-spfi.c @@ -160,16 +160,16 @@ static unsigned int spfi_pio_write32(struct img_spfi *spfi, const u32 *buf, unsigned int count = 0; u32 status; - while (count < max) { + while (count < max / 4) { spfi_writel(spfi, SPFI_INTERRUPT_SDFUL, SPFI_INTERRUPT_CLEAR); status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS); if (status & SPFI_INTERRUPT_SDFUL) break; - spfi_writel(spfi, buf[count / 4], SPFI_TX_32BIT_VALID_DATA); - count += 4; + spfi_writel(spfi, buf[count], SPFI_TX_32BIT_VALID_DATA); + count++; } - return count; + return count * 4; } static unsigned int spfi_pio_write8(struct img_spfi *spfi, const u8 *buf, @@ -196,17 +196,17 @@ static unsigned int spfi_pio_read32(struct img_spfi *spfi, u32 *buf, unsigned int count = 0; u32 status; - while (count < max) { + while (count < max / 4) { spfi_writel(spfi, SPFI_INTERRUPT_GDEX32BIT, SPFI_INTERRUPT_CLEAR); status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS); if (!(status & SPFI_INTERRUPT_GDEX32BIT)) break; - buf[count / 4] = spfi_readl(spfi, SPFI_RX_32BIT_VALID_DATA); - count += 4; + buf[count] = spfi_readl(spfi, SPFI_RX_32BIT_VALID_DATA); + count++; } - return count; + return count * 4; } static unsigned int spfi_pio_read8(struct img_spfi *spfi, u8 *buf, @@ -251,17 +251,15 @@ static int img_spfi_start_pio(struct spi_master *master, time_before(jiffies, timeout)) { unsigned int tx_count, rx_count; - switch (xfer->bits_per_word) { - case 32: + if (tx_bytes >= 4) tx_count = spfi_pio_write32(spfi, tx_buf, tx_bytes); - rx_count = spfi_pio_read32(spfi, rx_buf, rx_bytes); - break; - case 8: - default: + else tx_count = spfi_pio_write8(spfi, tx_buf, tx_bytes); + + if (rx_bytes >= 4) + rx_count = spfi_pio_read32(spfi, rx_buf, rx_bytes); + else rx_count = spfi_pio_read8(spfi, rx_buf, rx_bytes); - break; - } tx_buf += tx_count; rx_buf += rx_count; @@ -331,14 +329,11 @@ static int img_spfi_start_dma(struct spi_master *master, if (xfer->rx_buf) { rxconf.direction = DMA_DEV_TO_MEM; - switch (xfer->bits_per_word) { - case 32: + if (xfer->len % 4 == 0) { rxconf.src_addr = spfi->phys + SPFI_RX_32BIT_VALID_DATA; rxconf.src_addr_width = 4; rxconf.src_maxburst = 4; - break; - case 8: - default: + } else { rxconf.src_addr = spfi->phys + SPFI_RX_8BIT_VALID_DATA; rxconf.src_addr_width = 1; rxconf.src_maxburst = 4; @@ -358,18 +353,14 @@ static int img_spfi_start_dma(struct spi_master *master, if (xfer->tx_buf) { txconf.direction = DMA_MEM_TO_DEV; - switch (xfer->bits_per_word) { - case 32: + if (xfer->len % 4 == 0) { txconf.dst_addr = spfi->phys + SPFI_TX_32BIT_VALID_DATA; txconf.dst_addr_width = 4; txconf.dst_maxburst = 4; - break; - case 8: - default: + } else { txconf.dst_addr = spfi->phys + SPFI_TX_8BIT_VALID_DATA; txconf.dst_addr_width = 1; txconf.dst_maxburst = 4; - break; } dmaengine_slave_config(spfi->tx_ch, &txconf); @@ -508,9 +499,7 @@ static void img_spfi_set_cs(struct spi_device *spi, bool enable) static bool img_spfi_can_dma(struct spi_master *master, struct spi_device *spi, struct spi_transfer *xfer) { - if (xfer->bits_per_word == 8 && xfer->len > SPFI_8BIT_FIFO_SIZE) - return true; - if (xfer->bits_per_word == 32 && xfer->len > SPFI_32BIT_FIFO_SIZE) + if (xfer->len > SPFI_32BIT_FIFO_SIZE) return true; return false; } -- 2.7.4