From dc7f71f486f4f5fa96f6dcf86833da020cde8a11 Mon Sep 17 00:00:00 2001 From: "Thang Q. Nguyen" Date: Thu, 10 May 2012 11:17:10 +0700 Subject: [PATCH] sata_dwc_460ex: device tree may specify dma_channel Only channel 0 is currently support and the driver code is fixed on channel 0. This patch lets device node specifying dma-channel in case it is not 0. If no dma-channel property is specified, channel 0 is used as default. Signed-off-by: Thang Q. Nguyen Signed-off-by: Jeff Garzik --- drivers/ata/sata_dwc_460ex.c | 48 ++++++++++++++++++++++++++++---------------- 1 file changed, 31 insertions(+), 17 deletions(-) mode change 100644 => 100755 drivers/ata/sata_dwc_460ex.c diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c old mode 100644 new mode 100755 index ae13ef1..937aeb3 --- a/drivers/ata/sata_dwc_460ex.c +++ b/drivers/ata/sata_dwc_460ex.c @@ -158,6 +158,7 @@ enum { /* Assign HW handshaking interface (x) to destination / source peripheral */ #define DMA_CFG_HW_HS_DEST(int_num) (((int_num) & 0xF) << 11) #define DMA_CFG_HW_HS_SRC(int_num) (((int_num) & 0xF) << 7) +#define DMA_CFG_HW_CH_PRIOR(int_num) (((int_num) & 0xF) << 5) #define DMA_LLP_LMS(addr, master) (((addr) & 0xfffffffc) | (master)) /* @@ -318,6 +319,7 @@ struct sata_dwc_host_priv { u32 dma_interrupt_count; struct ahb_dma_regs *sata_dma_regs; struct device *dwc_dev; + int dma_channel; }; struct sata_dwc_host_priv host_pvt; /* @@ -437,15 +439,12 @@ static void clear_chan_interrupts(int c) */ static int dma_request_channel(void) { - int i; - - for (i = 0; i < DMA_NUM_CHANS; i++) { - if (!(in_le32(&(host_pvt.sata_dma_regs->dma_chan_en.low)) &\ - DMA_CHANNEL(i))) - return i; - } - dev_err(host_pvt.dwc_dev, "%s NO channel chan_en: 0x%08x\n", __func__, - in_le32(&(host_pvt.sata_dma_regs->dma_chan_en.low))); + /* Check if the channel is not currently in use */ + if (!(in_le32(&(host_pvt.sata_dma_regs->dma_chan_en.low)) & + DMA_CHANNEL(host_pvt.dma_channel))) + return host_pvt.dma_channel; + dev_err(host_pvt.dwc_dev, "%s Channel %d is currently in use\n", + __func__, host_pvt.dma_channel); return -1; } @@ -481,7 +480,8 @@ static irqreturn_t dma_dwc_interrupt(int irq, void *hsdev_instance) dev_dbg(ap->dev, "eot=0x%08x err=0x%08x pending=%d active port=%d\n", tfr_reg, err_reg, hsdevp->dma_pending[tag], port); - for (chan = 0; chan < DMA_NUM_CHANS; chan++) { + chan = host_pvt.dma_channel; + if (chan >= 0) { /* Check for end-of-transfer interrupt. */ if (tfr_reg & DMA_CHANNEL(chan)) { /* @@ -534,9 +534,9 @@ static irqreturn_t dma_dwc_interrupt(int irq, void *hsdev_instance) static int dma_request_interrupts(struct sata_dwc_device *hsdev, int irq) { int retval = 0; - int chan; + int chan = host_pvt.dma_channel; - for (chan = 0; chan < DMA_NUM_CHANS; chan++) { + if (chan >= 0) { /* Unmask error interrupt */ out_le32(&(host_pvt.sata_dma_regs)->interrupt_mask.error.low, DMA_ENABLE_CHAN(chan)); @@ -575,7 +575,10 @@ static int map_sg_to_lli(struct scatterlist *sg, int num_elems, int fis_len = 0; dma_addr_t next_llp; int bl; + int sms_val, dms_val; + sms_val = 0; + dms_val = 1 + host_pvt.dma_channel; dev_dbg(host_pvt.dwc_dev, "%s: sg=%p nelem=%d lli=%p dma_lli=0x%08x" " dmadr=0x%08x\n", __func__, sg, num_elems, lli, (u32)dma_lli, (u32)dmadr_addr); @@ -635,8 +638,8 @@ static int map_sg_to_lli(struct scatterlist *sg, int num_elems, lli[idx].ctl.low = cpu_to_le32( DMA_CTL_TTFC(DMA_CTL_TTFC_P2M_DMAC) | - DMA_CTL_SMS(0) | - DMA_CTL_DMS(1) | + DMA_CTL_SMS(sms_val) | + DMA_CTL_DMS(dms_val) | DMA_CTL_SRC_MSIZE(bl) | DMA_CTL_DST_MSIZE(bl) | DMA_CTL_SINC_NOCHANGE | @@ -651,8 +654,8 @@ static int map_sg_to_lli(struct scatterlist *sg, int num_elems, lli[idx].ctl.low = cpu_to_le32( DMA_CTL_TTFC(DMA_CTL_TTFC_M2P_PER) | - DMA_CTL_SMS(1) | - DMA_CTL_DMS(0) | + DMA_CTL_SMS(dms_val) | + DMA_CTL_DMS(sms_val) | DMA_CTL_SRC_MSIZE(bl) | DMA_CTL_DST_MSIZE(bl) | DMA_CTL_DINC_NOCHANGE | @@ -744,8 +747,10 @@ static int dma_dwc_xfer_setup(struct scatterlist *sg, int num_elems, /* Program the CFG register. */ out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].cfg.high), + DMA_CFG_HW_HS_SRC(dma_ch) | DMA_CFG_HW_HS_DEST(dma_ch) | DMA_CFG_PROTCTL | DMA_CFG_FCMOD_REQ); - out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].cfg.low), 0); + out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].cfg.low), + DMA_CFG_HW_CH_PRIOR(dma_ch)); /* Program the address of the linked list */ out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].llp.low), @@ -1660,6 +1665,8 @@ static int sata_dwc_probe(struct platform_device *ofdev) struct ata_host *host; struct ata_port_info pi = sata_dwc_port_info[0]; const struct ata_port_info *ppi[] = { &pi, NULL }; + struct device_node *np = ofdev->dev.of_node; + u32 dma_chan; /* Allocate DWC SATA device */ hsdev = kzalloc(sizeof(*hsdev), GFP_KERNEL); @@ -1669,6 +1676,13 @@ static int sata_dwc_probe(struct platform_device *ofdev) goto error; } + if (of_property_read_u32(np, "dma-channel", &dma_chan)) { + dev_warn(&ofdev->dev, "no dma-channel property set." + " Use channel 0\n"); + dma_chan = 0; + } + host_pvt.dma_channel = dma_chan; + /* Ioremap SATA registers */ base = of_iomap(ofdev->dev.of_node, 0); if (!base) { -- 2.7.4