[ARM] 3444/1: i.MX: Scatter-gather DMA emulation for i.MX/MX1
Patch from Pavel Pisa This patch contains simplified set of changes to add scatter-gather emulation capability into MX1 DMA support. The result should be still usable for next combination of DMA transfers Statter-Gather/linear/2D/FIFO to linear/2D/FIFO and linear/2D/FIFO to Statter-Gather/2D/FIFO The patch corrects channel priority allocation to be compatible with MX1 hardware implementation. Previous code has not been adapted from its PXA original. Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Pavel Pisa
Russell King
parent
7ba01f9728
commit
999331af45
@ -7,11 +7,18 @@
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* 03/03/2004 Sascha Hauer <sascha@saschahauer.de>
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* 2004-03-03 Sascha Hauer <sascha@saschahauer.de>
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* initial version heavily inspired by
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* linux/arch/arm/mach-pxa/dma.c
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*
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* 2005-04-17 Pavel Pisa <pisa@cmp.felk.cvut.cz>
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* Changed to support scatter gather DMA
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* by taking Russell's code from RiscPC
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*
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*/
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#undef DEBUG
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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@ -22,69 +29,368 @@
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#include <asm/irq.h>
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#include <asm/hardware.h>
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#include <asm/dma.h>
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#include <asm/arch/imx-dma.h>
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static struct dma_channel {
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char *name;
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void (*irq_handler) (int, void *, struct pt_regs *);
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void (*err_handler) (int, void *, struct pt_regs *);
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void *data;
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} dma_channels[11];
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struct imx_dma_channel imx_dma_channels[IMX_DMA_CHANNELS];
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/* set err_handler to NULL to have the standard info-only error handler */
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int
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imx_request_dma(char *name, imx_dma_prio prio,
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void (*irq_handler) (int, void *, struct pt_regs *),
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void (*err_handler) (int, void *, struct pt_regs *), void *data)
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/*
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* imx_dma_sg_next - prepare next chunk for scatter-gather DMA emulation
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* @dma_ch: i.MX DMA channel number
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* @lastcount: number of bytes transferred during last transfer
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*
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* Functions prepares DMA controller for next sg data chunk transfer.
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* The @lastcount argument informs function about number of bytes transferred
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* during last block. Zero value can be used for @lastcount to setup DMA
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* for the first chunk.
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*/
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static inline int imx_dma_sg_next(imx_dmach_t dma_ch, unsigned int lastcount)
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{
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unsigned long flags;
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int i, found = 0;
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struct imx_dma_channel *imxdma = &imx_dma_channels[dma_ch];
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unsigned int nextcount;
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unsigned int nextaddr;
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/* basic sanity checks */
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if (!name || !irq_handler)
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return -EINVAL;
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if (!imxdma->name) {
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printk(KERN_CRIT "%s: called for not allocated channel %d\n",
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__FUNCTION__, dma_ch);
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return 0;
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}
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local_irq_save(flags);
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imxdma->resbytes -= lastcount;
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/* try grabbing a DMA channel with the requested priority */
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for (i = prio; i < prio + (prio == DMA_PRIO_LOW) ? 8 : 4; i++) {
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if (!dma_channels[i].name) {
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found = 1;
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break;
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if (!imxdma->sg) {
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pr_debug("imxdma%d: no sg data\n", dma_ch);
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return 0;
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}
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imxdma->sgbc += lastcount;
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if ((imxdma->sgbc >= imxdma->sg->length) || !imxdma->resbytes) {
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if ((imxdma->sgcount <= 1) || !imxdma->resbytes) {
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pr_debug("imxdma%d: sg transfer limit reached\n",
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dma_ch);
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imxdma->sgcount=0;
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imxdma->sg = NULL;
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return 0;
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} else {
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imxdma->sgcount--;
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imxdma->sg++;
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imxdma->sgbc = 0;
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}
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}
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nextcount = imxdma->sg->length - imxdma->sgbc;
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nextaddr = imxdma->sg->dma_address + imxdma->sgbc;
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if (!found) {
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/* requested prio group is full, try hier priorities */
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for (i = prio - 1; i >= 0; i--) {
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if (!dma_channels[i].name) {
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found = 1;
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break;
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}
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}
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}
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if(imxdma->resbytes < nextcount)
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nextcount = imxdma->resbytes;
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if (found) {
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DIMR &= ~(1 << i);
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dma_channels[i].name = name;
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dma_channels[i].irq_handler = irq_handler;
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dma_channels[i].err_handler = err_handler;
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dma_channels[i].data = data;
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} else {
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printk(KERN_WARNING "No more available DMA channels for %s\n",
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name);
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i = -ENODEV;
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}
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if ((imxdma->dma_mode & DMA_MODE_MASK) == DMA_MODE_READ)
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DAR(dma_ch) = nextaddr;
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else
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SAR(dma_ch) = nextaddr;
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local_irq_restore(flags);
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return i;
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CNTR(dma_ch) = nextcount;
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pr_debug("imxdma%d: next sg chunk dst 0x%08x, src 0x%08x, size 0x%08x\n",
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dma_ch, DAR(dma_ch), SAR(dma_ch), CNTR(dma_ch));
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return nextcount;
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}
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void
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imx_free_dma(int dma_ch)
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/*
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* imx_dma_setup_sg_base - scatter-gather DMA emulation
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* @dma_ch: i.MX DMA channel number
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* @sg: pointer to the scatter-gather list/vector
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* @sgcount: scatter-gather list hungs count
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*
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* Functions sets up i.MX DMA state for emulated scatter-gather transfer
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* and sets up channel registers to be ready for the first chunk
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*/
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static int
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imx_dma_setup_sg_base(imx_dmach_t dma_ch,
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struct scatterlist *sg, unsigned int sgcount)
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{
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struct imx_dma_channel *imxdma = &imx_dma_channels[dma_ch];
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imxdma->sg = sg;
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imxdma->sgcount = sgcount;
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imxdma->sgbc = 0;
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return imx_dma_sg_next(dma_ch, 0);
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}
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/**
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* imx_dma_setup_single - setup i.MX DMA channel for linear memory to/from device transfer
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* @dma_ch: i.MX DMA channel number
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* @dma_address: the DMA/physical memory address of the linear data block
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* to transfer
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* @dma_length: length of the data block in bytes
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* @dev_addr: physical device port address
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* @dmamode: DMA transfer mode, %DMA_MODE_READ from the device to the memory
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* or %DMA_MODE_WRITE from memory to the device
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*
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* The function setups DMA channel source and destination addresses for transfer
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* specified by provided parameters. The scatter-gather emulation is disabled,
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* because linear data block
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* form the physical address range is transfered.
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* Return value: if incorrect parameters are provided -%EINVAL.
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* Zero indicates success.
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*/
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int
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imx_dma_setup_single(imx_dmach_t dma_ch, dma_addr_t dma_address,
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unsigned int dma_length, unsigned int dev_addr,
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dmamode_t dmamode)
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{
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struct imx_dma_channel *imxdma = &imx_dma_channels[dma_ch];
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imxdma->sg = NULL;
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imxdma->sgcount = 0;
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imxdma->dma_mode = dmamode;
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imxdma->resbytes = dma_length;
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if (!dma_address) {
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printk(KERN_ERR "imxdma%d: imx_dma_setup_single null address\n",
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dma_ch);
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return -EINVAL;
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}
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if (!dma_length) {
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printk(KERN_ERR "imxdma%d: imx_dma_setup_single zero length\n",
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dma_ch);
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return -EINVAL;
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}
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if ((dmamode & DMA_MODE_MASK) == DMA_MODE_READ) {
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pr_debug("imxdma%d: mx_dma_setup_single2dev dma_addressg=0x%08x dma_length=%d dev_addr=0x%08x for read\n",
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dma_ch, (unsigned int)dma_address, dma_length,
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dev_addr);
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SAR(dma_ch) = dev_addr;
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DAR(dma_ch) = (unsigned int)dma_address;
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} else if ((dmamode & DMA_MODE_MASK) == DMA_MODE_WRITE) {
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pr_debug("imxdma%d: mx_dma_setup_single2dev dma_addressg=0x%08x dma_length=%d dev_addr=0x%08x for write\n",
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dma_ch, (unsigned int)dma_address, dma_length,
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dev_addr);
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SAR(dma_ch) = (unsigned int)dma_address;
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DAR(dma_ch) = dev_addr;
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} else {
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printk(KERN_ERR "imxdma%d: imx_dma_setup_single bad dmamode\n",
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dma_ch);
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return -EINVAL;
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}
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CNTR(dma_ch) = dma_length;
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return 0;
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}
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/**
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* imx_dma_setup_sg - setup i.MX DMA channel SG list to/from device transfer
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* @dma_ch: i.MX DMA channel number
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* @sg: pointer to the scatter-gather list/vector
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* @sgcount: scatter-gather list hungs count
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* @dma_length: total length of the transfer request in bytes
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* @dev_addr: physical device port address
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* @dmamode: DMA transfer mode, %DMA_MODE_READ from the device to the memory
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* or %DMA_MODE_WRITE from memory to the device
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*
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* The function setups DMA channel state and registers to be ready for transfer
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* specified by provided parameters. The scatter-gather emulation is set up
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* according to the parameters.
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*
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* The full preparation of the transfer requires setup of more register
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* by the caller before imx_dma_enable() can be called.
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*
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* %BLR(dma_ch) holds transfer burst length in bytes, 0 means 64 bytes
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*
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* %RSSR(dma_ch) has to be set to the DMA request line source %DMA_REQ_xxx
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*
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* %CCR(dma_ch) has to specify transfer parameters, the next settings is typical
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* for linear or simple scatter-gather transfers if %DMA_MODE_READ is specified
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*
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* %CCR_DMOD_LINEAR | %CCR_DSIZ_32 | %CCR_SMOD_FIFO | %CCR_SSIZ_x
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*
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* The typical setup for %DMA_MODE_WRITE is specified by next options combination
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*
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* %CCR_SMOD_LINEAR | %CCR_SSIZ_32 | %CCR_DMOD_FIFO | %CCR_DSIZ_x
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*
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* Be carefull there and do not mistakenly mix source and target device
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* port sizes constants, they are really different:
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* %CCR_SSIZ_8, %CCR_SSIZ_16, %CCR_SSIZ_32,
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* %CCR_DSIZ_8, %CCR_DSIZ_16, %CCR_DSIZ_32
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*
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* Return value: if incorrect parameters are provided -%EINVAL.
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* Zero indicates success.
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*/
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int
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imx_dma_setup_sg(imx_dmach_t dma_ch,
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struct scatterlist *sg, unsigned int sgcount, unsigned int dma_length,
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unsigned int dev_addr, dmamode_t dmamode)
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{
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int res;
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struct imx_dma_channel *imxdma = &imx_dma_channels[dma_ch];
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imxdma->sg = NULL;
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imxdma->sgcount = 0;
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imxdma->dma_mode = dmamode;
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imxdma->resbytes = dma_length;
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if (!sg || !sgcount) {
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printk(KERN_ERR "imxdma%d: imx_dma_setup_sg epty sg list\n",
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dma_ch);
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return -EINVAL;
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}
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if (!sg->length) {
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printk(KERN_ERR "imxdma%d: imx_dma_setup_sg zero length\n",
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dma_ch);
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return -EINVAL;
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}
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if ((dmamode & DMA_MODE_MASK) == DMA_MODE_READ) {
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pr_debug("imxdma%d: mx_dma_setup_sg2dev sg=%p sgcount=%d total length=%d dev_addr=0x%08x for read\n",
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dma_ch, sg, sgcount, dma_length, dev_addr);
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SAR(dma_ch) = dev_addr;
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} else if ((dmamode & DMA_MODE_MASK) == DMA_MODE_WRITE) {
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pr_debug("imxdma%d: mx_dma_setup_sg2dev sg=%p sgcount=%d total length=%d dev_addr=0x%08x for write\n",
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dma_ch, sg, sgcount, dma_length, dev_addr);
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DAR(dma_ch) = dev_addr;
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} else {
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printk(KERN_ERR "imxdma%d: imx_dma_setup_sg bad dmamode\n",
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dma_ch);
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return -EINVAL;
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}
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res = imx_dma_setup_sg_base(dma_ch, sg, sgcount);
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if (res <= 0) {
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printk(KERN_ERR "imxdma%d: no sg chunk ready\n", dma_ch);
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return -EINVAL;
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}
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return 0;
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}
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/**
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* imx_dma_setup_handlers - setup i.MX DMA channel end and error notification handlers
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* @dma_ch: i.MX DMA channel number
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* @irq_handler: the pointer to the function called if the transfer
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* ends successfully
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* @err_handler: the pointer to the function called if the premature
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* end caused by error occurs
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* @data: user specified value to be passed to the handlers
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*/
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int
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imx_dma_setup_handlers(imx_dmach_t dma_ch,
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void (*irq_handler) (int, void *, struct pt_regs *),
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void (*err_handler) (int, void *, struct pt_regs *),
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void *data)
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{
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struct imx_dma_channel *imxdma = &imx_dma_channels[dma_ch];
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unsigned long flags;
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if (!imxdma->name) {
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printk(KERN_CRIT "%s: called for not allocated channel %d\n",
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__FUNCTION__, dma_ch);
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return -ENODEV;
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}
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local_irq_save(flags);
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DISR = (1 << dma_ch);
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imxdma->irq_handler = irq_handler;
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imxdma->err_handler = err_handler;
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imxdma->data = data;
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local_irq_restore(flags);
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return 0;
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}
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/**
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* imx_dma_enable - function to start i.MX DMA channel operation
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* @dma_ch: i.MX DMA channel number
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*
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* The channel has to be allocated by driver through imx_dma_request()
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* or imx_dma_request_by_prio() function.
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* The transfer parameters has to be set to the channel registers through
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* call of the imx_dma_setup_single() or imx_dma_setup_sg() function
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* and registers %BLR(dma_ch), %RSSR(dma_ch) and %CCR(dma_ch) has to
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* be set prior this function call by the channel user.
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*/
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void imx_dma_enable(imx_dmach_t dma_ch)
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{
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struct imx_dma_channel *imxdma = &imx_dma_channels[dma_ch];
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unsigned long flags;
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pr_debug("imxdma%d: imx_dma_enable\n", dma_ch);
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if (!imxdma->name) {
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printk(KERN_CRIT "%s: called for not allocated channel %d\n",
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__FUNCTION__, dma_ch);
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return;
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}
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local_irq_save(flags);
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DISR = (1 << dma_ch);
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DIMR &= ~(1 << dma_ch);
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CCR(dma_ch) |= CCR_CEN;
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local_irq_restore(flags);
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}
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/**
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* imx_dma_disable - stop, finish i.MX DMA channel operatin
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* @dma_ch: i.MX DMA channel number
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*/
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void imx_dma_disable(imx_dmach_t dma_ch)
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{
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unsigned long flags;
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if (!dma_channels[dma_ch].name) {
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pr_debug("imxdma%d: imx_dma_disable\n", dma_ch);
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local_irq_save(flags);
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DIMR |= (1 << dma_ch);
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CCR(dma_ch) &= ~CCR_CEN;
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DISR = (1 << dma_ch);
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local_irq_restore(flags);
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}
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/**
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* imx_dma_request - request/allocate specified channel number
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* @dma_ch: i.MX DMA channel number
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* @name: the driver/caller own non-%NULL identification
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*/
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int imx_dma_request(imx_dmach_t dma_ch, const char *name)
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{
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struct imx_dma_channel *imxdma = &imx_dma_channels[dma_ch];
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unsigned long flags;
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/* basic sanity checks */
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if (!name)
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return -EINVAL;
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if (dma_ch >= IMX_DMA_CHANNELS) {
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printk(KERN_CRIT "%s: called for non-existed channel %d\n",
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__FUNCTION__, dma_ch);
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return -EINVAL;
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}
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local_irq_save(flags);
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if (imxdma->name) {
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local_irq_restore(flags);
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return -ENODEV;
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}
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imxdma->name = name;
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imxdma->irq_handler = NULL;
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imxdma->err_handler = NULL;
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imxdma->data = NULL;
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imxdma->sg = NULL;
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local_irq_restore(flags);
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return 0;
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}
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/**
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* imx_dma_free - release previously acquired channel
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* @dma_ch: i.MX DMA channel number
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*/
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void imx_dma_free(imx_dmach_t dma_ch)
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{
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unsigned long flags;
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struct imx_dma_channel *imxdma = &imx_dma_channels[dma_ch];
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if (!imxdma->name) {
|
||||
printk(KERN_CRIT
|
||||
"%s: trying to free channel %d which is already freed\n",
|
||||
__FUNCTION__, dma_ch);
|
||||
@ -92,27 +398,84 @@ imx_free_dma(int dma_ch)
|
||||
}
|
||||
|
||||
local_irq_save(flags);
|
||||
DIMR &= ~(1 << dma_ch);
|
||||
dma_channels[dma_ch].name = NULL;
|
||||
/* Disable interrupts */
|
||||
DIMR |= (1 << dma_ch);
|
||||
CCR(dma_ch) &= ~CCR_CEN;
|
||||
imxdma->name = NULL;
|
||||
local_irq_restore(flags);
|
||||
}
|
||||
|
||||
static irqreturn_t
|
||||
dma_err_handler(int irq, void *dev_id, struct pt_regs *regs)
|
||||
/**
|
||||
* imx_dma_request_by_prio - find and request some of free channels best suiting requested priority
|
||||
* @dma_ch: i.MX DMA channel number
|
||||
* @name: the driver/caller own non-%NULL identification
|
||||
* @prio: one of the hardware distinguished priority level:
|
||||
* %DMA_PRIO_HIGH, %DMA_PRIO_MEDIUM, %DMA_PRIO_LOW
|
||||
*
|
||||
* This function tries to find free channel in the specified priority group
|
||||
* if the priority cannot be achieved it tries to look for free channel
|
||||
* in the higher and then even lower priority groups.
|
||||
*
|
||||
* Return value: If there is no free channel to allocate, -%ENODEV is returned.
|
||||
* Zero value indicates successful channel allocation.
|
||||
*/
|
||||
int
|
||||
imx_dma_request_by_prio(imx_dmach_t * pdma_ch, const char *name,
|
||||
imx_dma_prio prio)
|
||||
{
|
||||
int i;
|
||||
int best;
|
||||
|
||||
switch (prio) {
|
||||
case (DMA_PRIO_HIGH):
|
||||
best = 8;
|
||||
break;
|
||||
case (DMA_PRIO_MEDIUM):
|
||||
best = 4;
|
||||
break;
|
||||
case (DMA_PRIO_LOW):
|
||||
default:
|
||||
best = 0;
|
||||
break;
|
||||
}
|
||||
|
||||
for (i = best; i < IMX_DMA_CHANNELS; i++) {
|
||||
if (!imx_dma_request(i, name)) {
|
||||
*pdma_ch = i;
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
for (i = best - 1; i >= 0; i--) {
|
||||
if (!imx_dma_request(i, name)) {
|
||||
*pdma_ch = i;
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
printk(KERN_ERR "%s: no free DMA channel found\n", __FUNCTION__);
|
||||
|
||||
return -ENODEV;
|
||||
}
|
||||
|
||||
static irqreturn_t dma_err_handler(int irq, void *dev_id, struct pt_regs *regs)
|
||||
{
|
||||
int i, disr = DISR;
|
||||
struct dma_channel *channel;
|
||||
struct imx_dma_channel *channel;
|
||||
unsigned int err_mask = DBTOSR | DRTOSR | DSESR | DBOSR;
|
||||
|
||||
DISR = disr;
|
||||
for (i = 0; i < 11; i++) {
|
||||
channel = &dma_channels[i];
|
||||
for (i = 0; i < IMX_DMA_CHANNELS; i++) {
|
||||
channel = &imx_dma_channels[i];
|
||||
|
||||
if ( (err_mask & 1<<i) && channel->name && channel->err_handler) {
|
||||
if ((err_mask & 1 << i) && channel->name
|
||||
&& channel->err_handler) {
|
||||
channel->err_handler(i, channel->data, regs);
|
||||
continue;
|
||||
}
|
||||
|
||||
imx_dma_channels[i].sg = NULL;
|
||||
|
||||
if (DBTOSR & (1 << i)) {
|
||||
printk(KERN_WARNING
|
||||
"Burst timeout on channel %d (%s)\n",
|
||||
@ -141,17 +504,27 @@ dma_err_handler(int irq, void *dev_id, struct pt_regs *regs)
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
static irqreturn_t
|
||||
dma_irq_handler(int irq, void *dev_id, struct pt_regs *regs)
|
||||
static irqreturn_t dma_irq_handler(int irq, void *dev_id, struct pt_regs *regs)
|
||||
{
|
||||
int i, disr = DISR;
|
||||
|
||||
pr_debug("imxdma: dma_irq_handler called, disr=0x%08x\n",
|
||||
disr);
|
||||
|
||||
DISR = disr;
|
||||
for (i = 0; i < 11; i++) {
|
||||
for (i = 0; i < IMX_DMA_CHANNELS; i++) {
|
||||
if (disr & (1 << i)) {
|
||||
struct dma_channel *channel = &dma_channels[i];
|
||||
if (channel->name && channel->irq_handler) {
|
||||
channel->irq_handler(i, channel->data, regs);
|
||||
struct imx_dma_channel *channel = &imx_dma_channels[i];
|
||||
if (channel->name) {
|
||||
if (imx_dma_sg_next(i, CNTR(i))) {
|
||||
CCR(i) &= ~CCR_CEN;
|
||||
mb();
|
||||
CCR(i) |= CCR_CEN;
|
||||
} else {
|
||||
if (channel->irq_handler)
|
||||
channel->irq_handler(i,
|
||||
channel->data, regs);
|
||||
}
|
||||
} else {
|
||||
/*
|
||||
* IRQ for an unregistered DMA channel:
|
||||
@ -165,10 +538,10 @@ dma_irq_handler(int irq, void *dev_id, struct pt_regs *regs)
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
static int __init
|
||||
imx_dma_init(void)
|
||||
static int __init imx_dma_init(void)
|
||||
{
|
||||
int ret;
|
||||
int i;
|
||||
|
||||
/* reset DMA module */
|
||||
DCR = DCR_DRST;
|
||||
@ -189,15 +562,27 @@ imx_dma_init(void)
|
||||
DCR = DCR_DEN;
|
||||
|
||||
/* clear all interrupts */
|
||||
DISR = 0x3ff;
|
||||
DISR = (1 << IMX_DMA_CHANNELS) - 1;
|
||||
|
||||
/* enable interrupts */
|
||||
DIMR = 0;
|
||||
DIMR = (1 << IMX_DMA_CHANNELS) - 1;
|
||||
|
||||
for (i = 0; i < IMX_DMA_CHANNELS; i++) {
|
||||
imx_dma_channels[i].sg = NULL;
|
||||
imx_dma_channels[i].dma_num = i;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
arch_initcall(imx_dma_init);
|
||||
|
||||
EXPORT_SYMBOL(imx_request_dma);
|
||||
EXPORT_SYMBOL(imx_free_dma);
|
||||
EXPORT_SYMBOL(imx_dma_setup_single);
|
||||
EXPORT_SYMBOL(imx_dma_setup_sg);
|
||||
EXPORT_SYMBOL(imx_dma_setup_handlers);
|
||||
EXPORT_SYMBOL(imx_dma_enable);
|
||||
EXPORT_SYMBOL(imx_dma_disable);
|
||||
EXPORT_SYMBOL(imx_dma_request);
|
||||
EXPORT_SYMBOL(imx_dma_free);
|
||||
EXPORT_SYMBOL(imx_dma_request_by_prio);
|
||||
EXPORT_SYMBOL(imx_dma_channels);
|
||||
|
||||
@ -17,27 +17,16 @@
|
||||
* along with this program; if not, write to the Free Software
|
||||
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
||||
*/
|
||||
|
||||
#ifndef __ASM_ARCH_DMA_H
|
||||
#define __ASM_ARCH_DMA_H
|
||||
|
||||
/*
|
||||
* DMA registration
|
||||
*/
|
||||
|
||||
typedef enum {
|
||||
DMA_PRIO_HIGH = 0,
|
||||
DMA_PRIO_MEDIUM = 3,
|
||||
DMA_PRIO_LOW = 6
|
||||
DMA_PRIO_MEDIUM = 1,
|
||||
DMA_PRIO_LOW = 2
|
||||
} imx_dma_prio;
|
||||
|
||||
int imx_request_dma(char *name, imx_dma_prio prio,
|
||||
void (*irq_handler) (int, void *, struct pt_regs *),
|
||||
void (*err_handler) (int, void *, struct pt_regs *),
|
||||
void *data);
|
||||
|
||||
void imx_free_dma(int dma_ch);
|
||||
|
||||
|
||||
#define DMA_REQ_UART3_T 2
|
||||
#define DMA_REQ_UART3_R 3
|
||||
#define DMA_REQ_SSI2_T 4
|
||||
|
||||
90
include/asm-arm/arch-imx/imx-dma.h
Normal file
90
include/asm-arm/arch-imx/imx-dma.h
Normal file
@ -0,0 +1,90 @@
|
||||
/*
|
||||
* linux/include/asm-arm/imxads/dma.h
|
||||
*
|
||||
* Copyright (C) 1997,1998 Russell King
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation; either version 2 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program; if not, write to the Free Software
|
||||
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
||||
*/
|
||||
|
||||
#include <asm/dma.h>
|
||||
|
||||
#ifndef __ASM_ARCH_IMX_DMA_H
|
||||
#define __ASM_ARCH_IMX_DMA_H
|
||||
|
||||
#define IMX_DMA_CHANNELS 11
|
||||
|
||||
/*
|
||||
* struct imx_dma_channel - i.MX specific DMA extension
|
||||
* @name: name specified by DMA client
|
||||
* @irq_handler: client callback for end of transfer
|
||||
* @err_handler: client callback for error condition
|
||||
* @data: clients context data for callbacks
|
||||
* @dma_mode: direction of the transfer %DMA_MODE_READ or %DMA_MODE_WRITE
|
||||
* @sg: pointer to the actual read/written chunk for scatter-gather emulation
|
||||
* @sgbc: counter of processed bytes in the actual read/written chunk
|
||||
* @resbytes: total residual number of bytes to transfer
|
||||
* (it can be lower or same as sum of SG mapped chunk sizes)
|
||||
* @sgcount: number of chunks to be read/written
|
||||
*
|
||||
* Structure is used for IMX DMA processing. It would be probably good
|
||||
* @struct dma_struct in the future for external interfacing and use
|
||||
* @struct imx_dma_channel only as extension to it.
|
||||
*/
|
||||
|
||||
struct imx_dma_channel {
|
||||
const char *name;
|
||||
void (*irq_handler) (int, void *, struct pt_regs *);
|
||||
void (*err_handler) (int, void *, struct pt_regs *);
|
||||
void *data;
|
||||
dmamode_t dma_mode;
|
||||
struct scatterlist *sg;
|
||||
unsigned int sgbc;
|
||||
unsigned int sgcount;
|
||||
unsigned int resbytes;
|
||||
int dma_num;
|
||||
};
|
||||
|
||||
extern struct imx_dma_channel imx_dma_channels[IMX_DMA_CHANNELS];
|
||||
|
||||
|
||||
/* The type to distinguish channel numbers parameter from ordinal int type */
|
||||
typedef int imx_dmach_t;
|
||||
|
||||
int
|
||||
imx_dma_setup_single(imx_dmach_t dma_ch, dma_addr_t dma_address,
|
||||
unsigned int dma_length, unsigned int dev_addr, dmamode_t dmamode);
|
||||
|
||||
int
|
||||
imx_dma_setup_sg(imx_dmach_t dma_ch,
|
||||
struct scatterlist *sg, unsigned int sgcount, unsigned int dma_length,
|
||||
unsigned int dev_addr, dmamode_t dmamode);
|
||||
|
||||
int
|
||||
imx_dma_setup_handlers(imx_dmach_t dma_ch,
|
||||
void (*irq_handler) (int, void *, struct pt_regs *),
|
||||
void (*err_handler) (int, void *, struct pt_regs *), void *data);
|
||||
|
||||
void imx_dma_enable(imx_dmach_t dma_ch);
|
||||
|
||||
void imx_dma_disable(imx_dmach_t dma_ch);
|
||||
|
||||
int imx_dma_request(imx_dmach_t dma_ch, const char *name);
|
||||
|
||||
void imx_dma_free(imx_dmach_t dma_ch);
|
||||
|
||||
int imx_dma_request_by_prio(imx_dmach_t *pdma_ch, const char *name, imx_dma_prio prio);
|
||||
|
||||
|
||||
#endif /* _ASM_ARCH_IMX_DMA_H */
|
||||
Loading…
Reference in New Issue
Block a user