diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-imx.c | 150 |
1 files changed, 141 insertions, 9 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 930e47597db3..cc808a1c765c 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -56,6 +56,7 @@ /* The maximum bytes that a sdma BD can transfer.*/ #define MAX_SDMA_BD_BYTES (1 << 15) +#define MX51_ECSPI_CTRL_MAX_BURST 512 enum spi_imx_devtype { IMX1_CSPI, @@ -77,6 +78,7 @@ struct spi_imx_devtype_data { void (*reset)(struct spi_imx_data *); bool has_dmamode; unsigned int fifo_size; + bool dynamic_burst; enum spi_imx_devtype devtype; }; @@ -97,12 +99,14 @@ struct spi_imx_data { unsigned int bits_per_word; unsigned int spi_drctl; - unsigned int count; + unsigned int count, remainder; void (*tx)(struct spi_imx_data *); void (*rx)(struct spi_imx_data *); void *rx_buf; const void *tx_buf; unsigned int txfifo; /* number of words pushed in tx FIFO */ + unsigned int dynamic_burst, read_u32; + unsigned int word_mask; /* DMA */ bool usedma; @@ -231,6 +235,7 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, return false; spi_imx->wml = i; + spi_imx->dynamic_burst = 0; return true; } @@ -245,6 +250,7 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, #define MX51_ECSPI_CTRL_PREDIV_OFFSET 12 #define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18) #define MX51_ECSPI_CTRL_BL_OFFSET 20 +#define MX51_ECSPI_CTRL_BL_MASK (0xfff << 20) #define MX51_ECSPI_CONFIG 0x0c #define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0)) @@ -272,6 +278,102 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, #define MX51_ECSPI_TESTREG 0x20 #define MX51_ECSPI_TESTREG_LBC BIT(31) +static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx) +{ + unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); + unsigned int bytes_per_word; + + if (spi_imx->rx_buf) { +#ifdef __LITTLE_ENDIAN + bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word); + if (bytes_per_word == 1) + val = cpu_to_be32(val); + else if (bytes_per_word == 2) + val = (val << 16) | (val >> 16); +#endif + val &= spi_imx->word_mask; + *(u32 *)spi_imx->rx_buf = val; + spi_imx->rx_buf += sizeof(u32); + } +} + +static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx) +{ + unsigned int bytes_per_word; + + bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word); + if (spi_imx->read_u32) { + spi_imx_buf_rx_swap_u32(spi_imx); + return; + } + + if (bytes_per_word == 1) + spi_imx_buf_rx_u8(spi_imx); + else if (bytes_per_word == 2) + spi_imx_buf_rx_u16(spi_imx); +} + +static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx) +{ + u32 val = 0; + unsigned int bytes_per_word; + + if (spi_imx->tx_buf) { + val = *(u32 *)spi_imx->tx_buf; + val &= spi_imx->word_mask; + spi_imx->tx_buf += sizeof(u32); + } + + spi_imx->count -= sizeof(u32); +#ifdef __LITTLE_ENDIAN + bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word); + + if (bytes_per_word == 1) + val = cpu_to_be32(val); + else if (bytes_per_word == 2) + val = (val << 16) | (val >> 16); +#endif + writel(val, spi_imx->base + MXC_CSPITXDATA); +} + +static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx) +{ + u32 ctrl, val; + unsigned int bytes_per_word; + + if (spi_imx->count == spi_imx->remainder) { + ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL); + ctrl &= ~MX51_ECSPI_CTRL_BL_MASK; + if (spi_imx->count > MX51_ECSPI_CTRL_MAX_BURST) { + spi_imx->remainder = spi_imx->count % + MX51_ECSPI_CTRL_MAX_BURST; + val = MX51_ECSPI_CTRL_MAX_BURST * 8 - 1; + } else if (spi_imx->count >= sizeof(u32)) { + spi_imx->remainder = spi_imx->count % sizeof(u32); + val = (spi_imx->count - spi_imx->remainder) * 8 - 1; + } else { + spi_imx->remainder = 0; + val = spi_imx->bits_per_word - 1; + spi_imx->read_u32 = 0; + } + + ctrl |= (val << MX51_ECSPI_CTRL_BL_OFFSET); + writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL); + } + + if (spi_imx->count >= sizeof(u32)) { + spi_imx_buf_tx_swap_u32(spi_imx); + return; + } + + bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word); + + if (bytes_per_word == 1) + spi_imx_buf_tx_u8(spi_imx); + else if (bytes_per_word == 2) + spi_imx_buf_tx_u16(spi_imx); +} + /* MX51 eCSPI */ static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx, unsigned int fspi, unsigned int *fres) @@ -698,6 +800,7 @@ static struct spi_imx_devtype_data imx1_cspi_devtype_data = { .reset = mx1_reset, .fifo_size = 8, .has_dmamode = false, + .dynamic_burst = false, .devtype = IMX1_CSPI, }; @@ -709,6 +812,7 @@ static struct spi_imx_devtype_data imx21_cspi_devtype_data = { .reset = mx21_reset, .fifo_size = 8, .has_dmamode = false, + .dynamic_burst = false, .devtype = IMX21_CSPI, }; @@ -721,6 +825,7 @@ static struct spi_imx_devtype_data imx27_cspi_devtype_data = { .reset = mx21_reset, .fifo_size = 8, .has_dmamode = false, + .dynamic_burst = false, .devtype = IMX27_CSPI, }; @@ -732,6 +837,7 @@ static struct spi_imx_devtype_data imx31_cspi_devtype_data = { .reset = mx31_reset, .fifo_size = 8, .has_dmamode = false, + .dynamic_burst = false, .devtype = IMX31_CSPI, }; @@ -744,6 +850,7 @@ static struct spi_imx_devtype_data imx35_cspi_devtype_data = { .reset = mx31_reset, .fifo_size = 8, .has_dmamode = true, + .dynamic_burst = false, .devtype = IMX35_CSPI, }; @@ -755,6 +862,7 @@ static struct spi_imx_devtype_data imx51_ecspi_devtype_data = { .reset = mx51_ecspi_reset, .fifo_size = 64, .has_dmamode = true, + .dynamic_burst = true, .devtype = IMX51_ECSPI, }; @@ -827,6 +935,8 @@ static void spi_imx_push(struct spi_imx_data *spi_imx) while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) { if (!spi_imx->count) break; + if (spi_imx->txfifo && (spi_imx->count == spi_imx->remainder)) + break; spi_imx->tx(spi_imx); spi_imx->txfifo++; } @@ -920,15 +1030,37 @@ static int spi_imx_setupxfer(struct spi_device *spi, spi_imx->speed_hz = t->speed_hz; /* Initialize the functions for transfer */ - if (spi_imx->bits_per_word <= 8) { - spi_imx->rx = spi_imx_buf_rx_u8; - spi_imx->tx = spi_imx_buf_tx_u8; - } else if (spi_imx->bits_per_word <= 16) { - spi_imx->rx = spi_imx_buf_rx_u16; - spi_imx->tx = spi_imx_buf_tx_u16; + if (spi_imx->devtype_data->dynamic_burst) { + u32 mask; + + spi_imx->dynamic_burst = 0; + spi_imx->remainder = 0; + spi_imx->read_u32 = 1; + + mask = (1 << spi_imx->bits_per_word) - 1; + spi_imx->rx = spi_imx_buf_rx_swap; + spi_imx->tx = spi_imx_buf_tx_swap; + spi_imx->dynamic_burst = 1; + spi_imx->remainder = t->len; + + if (spi_imx->bits_per_word <= 8) + spi_imx->word_mask = mask << 24 | mask << 16 + | mask << 8 | mask; + else if (spi_imx->bits_per_word <= 16) + spi_imx->word_mask = mask << 16 | mask; + else + spi_imx->word_mask = mask; } else { - spi_imx->rx = spi_imx_buf_rx_u32; - spi_imx->tx = spi_imx_buf_tx_u32; + if (spi_imx->bits_per_word <= 8) { + spi_imx->rx = spi_imx_buf_rx_u8; + spi_imx->tx = spi_imx_buf_tx_u8; + } else if (spi_imx->bits_per_word <= 16) { + spi_imx->rx = spi_imx_buf_rx_u16; + spi_imx->tx = spi_imx_buf_tx_u16; + } else { + spi_imx->rx = spi_imx_buf_rx_u32; + spi_imx->tx = spi_imx_buf_tx_u32; + } } if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t)) |