diff options
Diffstat (limited to 'arch/arm/mach-imx/dma-v1.c')
| -rw-r--r-- | arch/arm/mach-imx/dma-v1.c | 845 |
1 files changed, 0 insertions, 845 deletions
diff --git a/arch/arm/mach-imx/dma-v1.c b/arch/arm/mach-imx/dma-v1.c deleted file mode 100644 index 3189a6004cf9..000000000000 --- a/arch/arm/mach-imx/dma-v1.c +++ /dev/null @@ -1,845 +0,0 @@ -/* - * linux/arch/arm/plat-mxc/dma-v1.c - * - * i.MX DMA registration and IRQ dispatching - * - * Copyright 2006 Pavel Pisa <pisa@cmp.felk.cvut.cz> - * Copyright 2008 Juergen Beisert, <kernel@pengutronix.de> - * Copyright 2008 Sascha Hauer, <s.hauer@pengutronix.de> - * - * 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., 51 Franklin Street, Fifth Floor, Boston, - * MA 02110-1301, USA. - */ - -#include <linux/module.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/interrupt.h> -#include <linux/err.h> -#include <linux/errno.h> -#include <linux/clk.h> -#include <linux/scatterlist.h> -#include <linux/io.h> - -#include <asm/irq.h> -#include <mach/hardware.h> -#include <mach/dma-v1.h> - -#define DMA_DCR 0x00 /* Control Register */ -#define DMA_DISR 0x04 /* Interrupt status Register */ -#define DMA_DIMR 0x08 /* Interrupt mask Register */ -#define DMA_DBTOSR 0x0c /* Burst timeout status Register */ -#define DMA_DRTOSR 0x10 /* Request timeout Register */ -#define DMA_DSESR 0x14 /* Transfer Error Status Register */ -#define DMA_DBOSR 0x18 /* Buffer overflow status Register */ -#define DMA_DBTOCR 0x1c /* Burst timeout control Register */ -#define DMA_WSRA 0x40 /* W-Size Register A */ -#define DMA_XSRA 0x44 /* X-Size Register A */ -#define DMA_YSRA 0x48 /* Y-Size Register A */ -#define DMA_WSRB 0x4c /* W-Size Register B */ -#define DMA_XSRB 0x50 /* X-Size Register B */ -#define DMA_YSRB 0x54 /* Y-Size Register B */ -#define DMA_SAR(x) (0x80 + ((x) << 6)) /* Source Address Registers */ -#define DMA_DAR(x) (0x84 + ((x) << 6)) /* Destination Address Registers */ -#define DMA_CNTR(x) (0x88 + ((x) << 6)) /* Count Registers */ -#define DMA_CCR(x) (0x8c + ((x) << 6)) /* Control Registers */ -#define DMA_RSSR(x) (0x90 + ((x) << 6)) /* Request source select Registers */ -#define DMA_BLR(x) (0x94 + ((x) << 6)) /* Burst length Registers */ -#define DMA_RTOR(x) (0x98 + ((x) << 6)) /* Request timeout Registers */ -#define DMA_BUCR(x) (0x98 + ((x) << 6)) /* Bus Utilization Registers */ -#define DMA_CCNR(x) (0x9C + ((x) << 6)) /* Channel counter Registers */ - -#define DCR_DRST (1<<1) -#define DCR_DEN (1<<0) -#define DBTOCR_EN (1<<15) -#define DBTOCR_CNT(x) ((x) & 0x7fff) -#define CNTR_CNT(x) ((x) & 0xffffff) -#define CCR_ACRPT (1<<14) -#define CCR_DMOD_LINEAR (0x0 << 12) -#define CCR_DMOD_2D (0x1 << 12) -#define CCR_DMOD_FIFO (0x2 << 12) -#define CCR_DMOD_EOBFIFO (0x3 << 12) -#define CCR_SMOD_LINEAR (0x0 << 10) -#define CCR_SMOD_2D (0x1 << 10) -#define CCR_SMOD_FIFO (0x2 << 10) -#define CCR_SMOD_EOBFIFO (0x3 << 10) -#define CCR_MDIR_DEC (1<<9) -#define CCR_MSEL_B (1<<8) -#define CCR_DSIZ_32 (0x0 << 6) -#define CCR_DSIZ_8 (0x1 << 6) -#define CCR_DSIZ_16 (0x2 << 6) -#define CCR_SSIZ_32 (0x0 << 4) -#define CCR_SSIZ_8 (0x1 << 4) -#define CCR_SSIZ_16 (0x2 << 4) -#define CCR_REN (1<<3) -#define CCR_RPT (1<<2) -#define CCR_FRC (1<<1) -#define CCR_CEN (1<<0) -#define RTOR_EN (1<<15) -#define RTOR_CLK (1<<14) -#define RTOR_PSC (1<<13) - -/* - * 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 - * @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 *); - void (*err_handler) (int, void *, int errcode); - void (*prog_handler) (int, void *, struct scatterlist *); - void *data; - unsigned int dma_mode; - struct scatterlist *sg; - unsigned int resbytes; - int dma_num; - - int in_use; - - u32 ccr_from_device; - u32 ccr_to_device; - - struct timer_list watchdog; - - int hw_chaining; -}; - -static void __iomem *imx_dmav1_baseaddr; - -static void imx_dmav1_writel(unsigned val, unsigned offset) -{ - __raw_writel(val, imx_dmav1_baseaddr + offset); -} - -static unsigned imx_dmav1_readl(unsigned offset) -{ - return __raw_readl(imx_dmav1_baseaddr + offset); -} - -static struct imx_dma_channel imx_dma_channels[IMX_DMA_CHANNELS]; - -static struct clk *dma_clk; - -static int imx_dma_hw_chain(struct imx_dma_channel *imxdma) -{ - if (cpu_is_mx27()) - return imxdma->hw_chaining; - else - return 0; -} - -/* - * imx_dma_sg_next - prepare next chunk for scatter-gather DMA emulation - */ -static inline int imx_dma_sg_next(int channel, struct scatterlist *sg) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - unsigned long now; - - if (!imxdma->name) { - printk(KERN_CRIT "%s: called for not allocated channel %d\n", - __func__, channel); - return 0; - } - - now = min(imxdma->resbytes, sg->length); - if (imxdma->resbytes != IMX_DMA_LENGTH_LOOP) - imxdma->resbytes -= now; - - if ((imxdma->dma_mode & DMA_MODE_MASK) == DMA_MODE_READ) - imx_dmav1_writel(sg->dma_address, DMA_DAR(channel)); - else - imx_dmav1_writel(sg->dma_address, DMA_SAR(channel)); - - imx_dmav1_writel(now, DMA_CNTR(channel)); - - pr_debug("imxdma%d: next sg chunk dst 0x%08x, src 0x%08x, " - "size 0x%08x\n", channel, - imx_dmav1_readl(DMA_DAR(channel)), - imx_dmav1_readl(DMA_SAR(channel)), - imx_dmav1_readl(DMA_CNTR(channel))); - - return now; -} - -/** - * imx_dma_setup_single - setup i.MX DMA channel for linear memory to/from - * device transfer - * - * @channel: i.MX DMA channel number - * @dma_address: the DMA/physical memory address of the linear data block - * to transfer - * @dma_length: length of the data block in bytes - * @dev_addr: physical device port address - * @dmamode: DMA transfer mode, %DMA_MODE_READ from the device to the memory - * or %DMA_MODE_WRITE from memory to the device - * - * Return value: if incorrect parameters are provided -%EINVAL. - * Zero indicates success. - */ -int -imx_dma_setup_single(int channel, dma_addr_t dma_address, - unsigned int dma_length, unsigned int dev_addr, - unsigned int dmamode) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - - imxdma->sg = NULL; - imxdma->dma_mode = dmamode; - - if (!dma_address) { - printk(KERN_ERR "imxdma%d: imx_dma_setup_single null address\n", - channel); - return -EINVAL; - } - - if (!dma_length) { - printk(KERN_ERR "imxdma%d: imx_dma_setup_single zero length\n", - channel); - return -EINVAL; - } - - if ((dmamode & DMA_MODE_MASK) == DMA_MODE_READ) { - pr_debug("imxdma%d: %s dma_addressg=0x%08x dma_length=%d " - "dev_addr=0x%08x for read\n", - channel, __func__, (unsigned int)dma_address, - dma_length, dev_addr); - - imx_dmav1_writel(dev_addr, DMA_SAR(channel)); - imx_dmav1_writel(dma_address, DMA_DAR(channel)); - imx_dmav1_writel(imxdma->ccr_from_device, DMA_CCR(channel)); - } else if ((dmamode & DMA_MODE_MASK) == DMA_MODE_WRITE) { - pr_debug("imxdma%d: %s dma_addressg=0x%08x dma_length=%d " - "dev_addr=0x%08x for write\n", - channel, __func__, (unsigned int)dma_address, - dma_length, dev_addr); - - imx_dmav1_writel(dma_address, DMA_SAR(channel)); - imx_dmav1_writel(dev_addr, DMA_DAR(channel)); - imx_dmav1_writel(imxdma->ccr_to_device, - DMA_CCR(channel)); - } else { - printk(KERN_ERR "imxdma%d: imx_dma_setup_single bad dmamode\n", - channel); - return -EINVAL; - } - - imx_dmav1_writel(dma_length, DMA_CNTR(channel)); - - return 0; -} -EXPORT_SYMBOL(imx_dma_setup_single); - -/** - * imx_dma_setup_sg - setup i.MX DMA channel SG list to/from device transfer - * @channel: i.MX DMA channel number - * @sg: pointer to the scatter-gather list/vector - * @sgcount: scatter-gather list hungs count - * @dma_length: total length of the transfer request in bytes - * @dev_addr: physical device port address - * @dmamode: DMA transfer mode, %DMA_MODE_READ from the device to the memory - * or %DMA_MODE_WRITE from memory to the device - * - * The function sets up DMA channel state and registers to be ready for - * transfer specified by provided parameters. The scatter-gather emulation - * is set up according to the parameters. - * - * The full preparation of the transfer requires setup of more register - * by the caller before imx_dma_enable() can be called. - * - * %BLR(channel) holds transfer burst length in bytes, 0 means 64 bytes - * - * %RSSR(channel) has to be set to the DMA request line source %DMA_REQ_xxx - * - * %CCR(channel) has to specify transfer parameters, the next settings is - * typical for linear or simple scatter-gather transfers if %DMA_MODE_READ is - * specified - * - * %CCR_DMOD_LINEAR | %CCR_DSIZ_32 | %CCR_SMOD_FIFO | %CCR_SSIZ_x - * - * The typical setup for %DMA_MODE_WRITE is specified by next options - * combination - * - * %CCR_SMOD_LINEAR | %CCR_SSIZ_32 | %CCR_DMOD_FIFO | %CCR_DSIZ_x - * - * Be careful here and do not mistakenly mix source and target device - * port sizes constants, they are really different: - * %CCR_SSIZ_8, %CCR_SSIZ_16, %CCR_SSIZ_32, - * %CCR_DSIZ_8, %CCR_DSIZ_16, %CCR_DSIZ_32 - * - * Return value: if incorrect parameters are provided -%EINVAL. - * Zero indicates success. - */ -int -imx_dma_setup_sg(int channel, - struct scatterlist *sg, unsigned int sgcount, - unsigned int dma_length, unsigned int dev_addr, - unsigned int dmamode) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - - if (imxdma->in_use) - return -EBUSY; - - imxdma->sg = sg; - imxdma->dma_mode = dmamode; - imxdma->resbytes = dma_length; - - if (!sg || !sgcount) { - printk(KERN_ERR "imxdma%d: imx_dma_setup_sg empty sg list\n", - channel); - return -EINVAL; - } - - if (!sg->length) { - printk(KERN_ERR "imxdma%d: imx_dma_setup_sg zero length\n", - channel); - return -EINVAL; - } - - if ((dmamode & DMA_MODE_MASK) == DMA_MODE_READ) { - pr_debug("imxdma%d: %s sg=%p sgcount=%d total length=%d " - "dev_addr=0x%08x for read\n", - channel, __func__, sg, sgcount, dma_length, dev_addr); - - imx_dmav1_writel(dev_addr, DMA_SAR(channel)); - imx_dmav1_writel(imxdma->ccr_from_device, DMA_CCR(channel)); - } else if ((dmamode & DMA_MODE_MASK) == DMA_MODE_WRITE) { - pr_debug("imxdma%d: %s sg=%p sgcount=%d total length=%d " - "dev_addr=0x%08x for write\n", - channel, __func__, sg, sgcount, dma_length, dev_addr); - - imx_dmav1_writel(dev_addr, DMA_DAR(channel)); - imx_dmav1_writel(imxdma->ccr_to_device, DMA_CCR(channel)); - } else { - printk(KERN_ERR "imxdma%d: imx_dma_setup_sg bad dmamode\n", - channel); - return -EINVAL; - } - - imx_dma_sg_next(channel, sg); - - return 0; -} -EXPORT_SYMBOL(imx_dma_setup_sg); - -int -imx_dma_config_channel(int channel, unsigned int config_port, - unsigned int config_mem, unsigned int dmareq, int hw_chaining) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - u32 dreq = 0; - - imxdma->hw_chaining = 0; - - if (hw_chaining) { - imxdma->hw_chaining = 1; - if (!imx_dma_hw_chain(imxdma)) - return -EINVAL; - } - - if (dmareq) - dreq = CCR_REN; - - imxdma->ccr_from_device = config_port | (config_mem << 2) | dreq; - imxdma->ccr_to_device = config_mem | (config_port << 2) | dreq; - - imx_dmav1_writel(dmareq, DMA_RSSR(channel)); - - return 0; -} -EXPORT_SYMBOL(imx_dma_config_channel); - -void imx_dma_config_burstlen(int channel, unsigned int burstlen) -{ - imx_dmav1_writel(burstlen, DMA_BLR(channel)); -} -EXPORT_SYMBOL(imx_dma_config_burstlen); - -/** - * imx_dma_setup_handlers - setup i.MX DMA channel end and error notification - * handlers - * @channel: i.MX DMA channel number - * @irq_handler: the pointer to the function called if the transfer - * ends successfully - * @err_handler: the pointer to the function called if the premature - * end caused by error occurs - * @data: user specified value to be passed to the handlers - */ -int -imx_dma_setup_handlers(int channel, - void (*irq_handler) (int, void *), - void (*err_handler) (int, void *, int), - void *data) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - unsigned long flags; - - if (!imxdma->name) { - printk(KERN_CRIT "%s: called for not allocated channel %d\n", - __func__, channel); - return -ENODEV; - } - - local_irq_save(flags); - imx_dmav1_writel(1 << channel, DMA_DISR); - imxdma->irq_handler = irq_handler; - imxdma->err_handler = err_handler; - imxdma->data = data; - local_irq_restore(flags); - return 0; -} -EXPORT_SYMBOL(imx_dma_setup_handlers); - -/** - * imx_dma_setup_progression_handler - setup i.MX DMA channel progression - * handlers - * @channel: i.MX DMA channel number - * @prog_handler: the pointer to the function called if the transfer progresses - */ -int -imx_dma_setup_progression_handler(int channel, - void (*prog_handler) (int, void*, struct scatterlist*)) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - unsigned long flags; - - if (!imxdma->name) { - printk(KERN_CRIT "%s: called for not allocated channel %d\n", - __func__, channel); - return -ENODEV; - } - - local_irq_save(flags); - imxdma->prog_handler = prog_handler; - local_irq_restore(flags); - return 0; -} -EXPORT_SYMBOL(imx_dma_setup_progression_handler); - -/** - * imx_dma_enable - function to start i.MX DMA channel operation - * @channel: i.MX DMA channel number - * - * The channel has to be allocated by driver through imx_dma_request() - * or imx_dma_request_by_prio() function. - * The transfer parameters has to be set to the channel registers through - * call of the imx_dma_setup_single() or imx_dma_setup_sg() function - * and registers %BLR(channel), %RSSR(channel) and %CCR(channel) has to - * be set prior this function call by the channel user. - */ -void imx_dma_enable(int channel) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - unsigned long flags; - - pr_debug("imxdma%d: imx_dma_enable\n", channel); - - if (!imxdma->name) { - printk(KERN_CRIT "%s: called for not allocated channel %d\n", - __func__, channel); - return; - } - - if (imxdma->in_use) - return; - - local_irq_save(flags); - - imx_dmav1_writel(1 << channel, DMA_DISR); - imx_dmav1_writel(imx_dmav1_readl(DMA_DIMR) & ~(1 << channel), DMA_DIMR); - imx_dmav1_writel(imx_dmav1_readl(DMA_CCR(channel)) | CCR_CEN | - CCR_ACRPT, DMA_CCR(channel)); - - if ((cpu_is_mx21() || cpu_is_mx27()) && - imxdma->sg && imx_dma_hw_chain(imxdma)) { - imxdma->sg = sg_next(imxdma->sg); - if (imxdma->sg) { - u32 tmp; - imx_dma_sg_next(channel, imxdma->sg); - tmp = imx_dmav1_readl(DMA_CCR(channel)); - imx_dmav1_writel(tmp | CCR_RPT | CCR_ACRPT, - DMA_CCR(channel)); - } - } - imxdma->in_use = 1; - - local_irq_restore(flags); -} -EXPORT_SYMBOL(imx_dma_enable); - -/** - * imx_dma_disable - stop, finish i.MX DMA channel operatin - * @channel: i.MX DMA channel number - */ -void imx_dma_disable(int channel) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - unsigned long flags; - - pr_debug("imxdma%d: imx_dma_disable\n", channel); - - if (imx_dma_hw_chain(imxdma)) - del_timer(&imxdma->watchdog); - - local_irq_save(flags); - imx_dmav1_writel(imx_dmav1_readl(DMA_DIMR) | (1 << channel), DMA_DIMR); - imx_dmav1_writel(imx_dmav1_readl(DMA_CCR(channel)) & ~CCR_CEN, - DMA_CCR(channel)); - imx_dmav1_writel(1 << channel, DMA_DISR); - imxdma->in_use = 0; - local_irq_restore(flags); -} -EXPORT_SYMBOL(imx_dma_disable); - -static void imx_dma_watchdog(unsigned long chno) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[chno]; - - imx_dmav1_writel(0, DMA_CCR(chno)); - imxdma->in_use = 0; - imxdma->sg = NULL; - - if (imxdma->err_handler) - imxdma->err_handler(chno, imxdma->data, IMX_DMA_ERR_TIMEOUT); -} - -static irqreturn_t dma_err_handler(int irq, void *dev_id) -{ - int i, disr; - struct imx_dma_channel *imxdma; - unsigned int err_mask; - int errcode; - - disr = imx_dmav1_readl(DMA_DISR); - - err_mask = imx_dmav1_readl(DMA_DBTOSR) | - imx_dmav1_readl(DMA_DRTOSR) | - imx_dmav1_readl(DMA_DSESR) | - imx_dmav1_readl(DMA_DBOSR); - - if (!err_mask) - return IRQ_HANDLED; - - imx_dmav1_writel(disr & err_mask, DMA_DISR); - - for (i = 0; i < IMX_DMA_CHANNELS; i++) { - if (!(err_mask & (1 << i))) - continue; - imxdma = &imx_dma_channels[i]; - errcode = 0; - - if (imx_dmav1_readl(DMA_DBTOSR) & (1 << i)) { - imx_dmav1_writel(1 << i, DMA_DBTOSR); - errcode |= IMX_DMA_ERR_BURST; - } - if (imx_dmav1_readl(DMA_DRTOSR) & (1 << i)) { - imx_dmav1_writel(1 << i, DMA_DRTOSR); - errcode |= IMX_DMA_ERR_REQUEST; - } - if (imx_dmav1_readl(DMA_DSESR) & (1 << i)) { - imx_dmav1_writel(1 << i, DMA_DSESR); - errcode |= IMX_DMA_ERR_TRANSFER; - } - if (imx_dmav1_readl(DMA_DBOSR) & (1 << i)) { - imx_dmav1_writel(1 << i, DMA_DBOSR); - errcode |= IMX_DMA_ERR_BUFFER; - } - if (imxdma->name && imxdma->err_handler) { - imxdma->err_handler(i, imxdma->data, errcode); - continue; - } - - imx_dma_channels[i].sg = NULL; - - printk(KERN_WARNING - "DMA timeout on channel %d (%s) -%s%s%s%s\n", - i, imxdma->name, - errcode & IMX_DMA_ERR_BURST ? " burst" : "", - errcode & IMX_DMA_ERR_REQUEST ? " request" : "", - errcode & IMX_DMA_ERR_TRANSFER ? " transfer" : "", - errcode & IMX_DMA_ERR_BUFFER ? " buffer" : ""); - } - return IRQ_HANDLED; -} - -static void dma_irq_handle_channel(int chno) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[chno]; - - if (!imxdma->name) { - /* - * IRQ for an unregistered DMA channel: - * let's clear the interrupts and disable it. - */ - printk(KERN_WARNING - "spurious IRQ for DMA channel %d\n", chno); - return; - } - - if (imxdma->sg) { - u32 tmp; - struct scatterlist *current_sg = imxdma->sg; - imxdma->sg = sg_next(imxdma->sg); - - if (imxdma->sg) { - imx_dma_sg_next(chno, imxdma->sg); - - tmp = imx_dmav1_readl(DMA_CCR(chno)); - - if (imx_dma_hw_chain(imxdma)) { - /* FIXME: The timeout should probably be - * configurable - */ - mod_timer(&imxdma->watchdog, - jiffies + msecs_to_jiffies(500)); - - tmp |= CCR_CEN | CCR_RPT | CCR_ACRPT; - imx_dmav1_writel(tmp, DMA_CCR(chno)); - } else { - imx_dmav1_writel(tmp & ~CCR_CEN, DMA_CCR(chno)); - tmp |= CCR_CEN; - } - - imx_dmav1_writel(tmp, DMA_CCR(chno)); - - if (imxdma->prog_handler) - imxdma->prog_handler(chno, imxdma->data, - current_sg); - - return; - } - - if (imx_dma_hw_chain(imxdma)) { - del_timer(&imxdma->watchdog); - return; - } - } - - imx_dmav1_writel(0, DMA_CCR(chno)); - imxdma->in_use = 0; - if (imxdma->irq_handler) - imxdma->irq_handler(chno, imxdma->data); -} - -static irqreturn_t dma_irq_handler(int irq, void *dev_id) -{ - int i, disr; - - if (cpu_is_mx21() || cpu_is_mx27()) - dma_err_handler(irq, dev_id); - - disr = imx_dmav1_readl(DMA_DISR); - - pr_debug("imxdma: dma_irq_handler called, disr=0x%08x\n", - disr); - - imx_dmav1_writel(disr, DMA_DISR); - for (i = 0; i < IMX_DMA_CHANNELS; i++) { - if (disr & (1 << i)) - dma_irq_handle_channel(i); - } - - return IRQ_HANDLED; -} - -/** - * imx_dma_request - request/allocate specified channel number - * @channel: i.MX DMA channel number - * @name: the driver/caller own non-%NULL identification - */ -int imx_dma_request(int channel, const char *name) -{ - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - unsigned long flags; - int ret = 0; - - /* basic sanity checks */ - if (!name) - return -EINVAL; - - if (channel >= IMX_DMA_CHANNELS) { - printk(KERN_CRIT "%s: called for non-existed channel %d\n", - __func__, channel); - return -EINVAL; - } - - local_irq_save(flags); - if (imxdma->name) { - local_irq_restore(flags); - return -EBUSY; - } - memset(imxdma, 0, sizeof(*imxdma)); - imxdma->name = name; - local_irq_restore(flags); /* request_irq() can block */ - - if (cpu_is_mx21() || cpu_is_mx27()) { - ret = request_irq(MX2x_INT_DMACH0 + channel, - dma_irq_handler, 0, "DMA", NULL); - if (ret) { - imxdma->name = NULL; - pr_crit("Can't register IRQ %d for DMA channel %d\n", - MX2x_INT_DMACH0 + channel, channel); - return ret; - } - init_timer(&imxdma->watchdog); - imxdma->watchdog.function = &imx_dma_watchdog; - imxdma->watchdog.data = channel; - } - - return ret; -} -EXPORT_SYMBOL(imx_dma_request); - -/** - * imx_dma_free - release previously acquired channel - * @channel: i.MX DMA channel number - */ -void imx_dma_free(int channel) -{ - unsigned long flags; - struct imx_dma_channel *imxdma = &imx_dma_channels[channel]; - - if (!imxdma->name) { - printk(KERN_CRIT - "%s: trying to free free channel %d\n", - __func__, channel); - return; - } - - local_irq_save(flags); - /* Disable interrupts */ - imx_dma_disable(channel); - imxdma->name = NULL; - - if (cpu_is_mx21() || cpu_is_mx27()) - free_irq(MX2x_INT_DMACH0 + channel, NULL); - - local_irq_restore(flags); -} -EXPORT_SYMBOL(imx_dma_free); - -/** - * imx_dma_request_by_prio - find and request some of free channels best - * suiting requested priority - * @channel: i.MX DMA channel number - * @name: the driver/caller own non-%NULL identification - * - * This function tries to find a 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. - * On successful allocation channel is returned. - */ -int imx_dma_request_by_prio(const char *name, enum 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)) - return i; - - for (i = best - 1; i >= 0; i--) - if (!imx_dma_request(i, name)) - return i; - - printk(KERN_ERR "%s: no free DMA channel found\n", __func__); - - return -ENODEV; -} -EXPORT_SYMBOL(imx_dma_request_by_prio); - -static int __init imx_dma_init(void) -{ - int ret = 0; - int i; - - if (cpu_is_mx1()) - imx_dmav1_baseaddr = MX1_IO_ADDRESS(MX1_DMA_BASE_ADDR); - else if (cpu_is_mx21()) - imx_dmav1_baseaddr = MX21_IO_ADDRESS(MX21_DMA_BASE_ADDR); - else if (cpu_is_mx27()) - imx_dmav1_baseaddr = MX27_IO_ADDRESS(MX27_DMA_BASE_ADDR); - else - return 0; - - dma_clk = clk_get(NULL, "dma"); - if (IS_ERR(dma_clk)) - return PTR_ERR(dma_clk); - clk_enable(dma_clk); - - /* reset DMA module */ - imx_dmav1_writel(DCR_DRST, DMA_DCR); - - if (cpu_is_mx1()) { - ret = request_irq(MX1_DMA_INT, dma_irq_handler, 0, "DMA", NULL); - if (ret) { - pr_crit("Wow! Can't register IRQ for DMA\n"); - return ret; - } - - ret = request_irq(MX1_DMA_ERR, dma_err_handler, 0, "DMA", NULL); - if (ret) { - pr_crit("Wow! Can't register ERRIRQ for DMA\n"); - free_irq(MX1_DMA_INT, NULL); - return ret; - } - } - - /* enable DMA module */ - imx_dmav1_writel(DCR_DEN, DMA_DCR); - - /* clear all interrupts */ - imx_dmav1_writel((1 << IMX_DMA_CHANNELS) - 1, DMA_DISR); - - /* disable interrupts */ - imx_dmav1_writel((1 << IMX_DMA_CHANNELS) - 1, DMA_DIMR); - - 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); |
