| /* |
| * linux/arch/arm/plat-mxc/dma-mx1-mx2.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/errno.h> |
| #include <linux/clk.h> |
| #include <linux/scatterlist.h> |
| #include <linux/io.h> |
| |
| #include <asm/system.h> |
| #include <asm/irq.h> |
| #include <mach/hardware.h> |
| #include <mach/dma-mx1-mx2.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 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); |
| imxdma->resbytes -= now; |
| |
| if ((imxdma->dma_mode & DMA_MODE_MASK) == DMA_MODE_READ) |
| __raw_writel(sg->dma_address, DMA_BASE + DMA_DAR(channel)); |
| else |
| __raw_writel(sg->dma_address, DMA_BASE + DMA_SAR(channel)); |
| |
| __raw_writel(now, DMA_BASE + DMA_CNTR(channel)); |
| |
| pr_debug("imxdma%d: next sg chunk dst 0x%08x, src 0x%08x, " |
| "size 0x%08x\n", channel, |
| __raw_readl(DMA_BASE + DMA_DAR(channel)), |
| __raw_readl(DMA_BASE + DMA_SAR(channel)), |
| __raw_readl(DMA_BASE + 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); |
| |
| __raw_writel(dev_addr, DMA_BASE + DMA_SAR(channel)); |
| __raw_writel(dma_address, DMA_BASE + DMA_DAR(channel)); |
| __raw_writel(imxdma->ccr_from_device, |
| DMA_BASE + 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); |
| |
| __raw_writel(dma_address, DMA_BASE + DMA_SAR(channel)); |
| __raw_writel(dev_addr, DMA_BASE + DMA_DAR(channel)); |
| __raw_writel(imxdma->ccr_to_device, |
| DMA_BASE + DMA_CCR(channel)); |
| } else { |
| printk(KERN_ERR "imxdma%d: imx_dma_setup_single bad dmamode\n", |
| channel); |
| return -EINVAL; |
| } |
| |
| __raw_writel(dma_length, DMA_BASE + 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 epty 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); |
| |
| __raw_writel(dev_addr, DMA_BASE + DMA_SAR(channel)); |
| __raw_writel(imxdma->ccr_from_device, |
| DMA_BASE + 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); |
| |
| __raw_writel(dev_addr, DMA_BASE + DMA_DAR(channel)); |
| __raw_writel(imxdma->ccr_to_device, |
| DMA_BASE + 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; |
| |
| __raw_writel(dmareq, DMA_BASE + DMA_RSSR(channel)); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(imx_dma_config_channel); |
| |
| void imx_dma_config_burstlen(int channel, unsigned int burstlen) |
| { |
| __raw_writel(burstlen, DMA_BASE + 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); |
| __raw_writel(1 << channel, DMA_BASE + 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); |
| |
| __raw_writel(1 << channel, DMA_BASE + DMA_DISR); |
| __raw_writel(__raw_readl(DMA_BASE + DMA_DIMR) & ~(1 << channel), |
| DMA_BASE + DMA_DIMR); |
| __raw_writel(__raw_readl(DMA_BASE + DMA_CCR(channel)) | CCR_CEN | |
| CCR_ACRPT, |
| DMA_BASE + DMA_CCR(channel)); |
| |
| #ifdef CONFIG_ARCH_MX2 |
| if (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 = __raw_readl(DMA_BASE + DMA_CCR(channel)); |
| __raw_writel(tmp | CCR_RPT | CCR_ACRPT, |
| DMA_BASE + DMA_CCR(channel)); |
| } |
| } |
| #endif |
| 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); |
| __raw_writel(__raw_readl(DMA_BASE + DMA_DIMR) | (1 << channel), |
| DMA_BASE + DMA_DIMR); |
| __raw_writel(__raw_readl(DMA_BASE + DMA_CCR(channel)) & ~CCR_CEN, |
| DMA_BASE + DMA_CCR(channel)); |
| __raw_writel(1 << channel, DMA_BASE + 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]; |
| |
| __raw_writel(0, DMA_BASE + 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 = __raw_readl(DMA_BASE + DMA_DISR); |
| |
| err_mask = __raw_readl(DMA_BASE + DMA_DBTOSR) | |
| __raw_readl(DMA_BASE + DMA_DRTOSR) | |
| __raw_readl(DMA_BASE + DMA_DSESR) | |
| __raw_readl(DMA_BASE + DMA_DBOSR); |
| |
| if (!err_mask) |
| return IRQ_HANDLED; |
| |
| __raw_writel(disr & err_mask, DMA_BASE + DMA_DISR); |
| |
| for (i = 0; i < IMX_DMA_CHANNELS; i++) { |
| if (!(err_mask & (1 << i))) |
| continue; |
| imxdma = &imx_dma_channels[i]; |
| errcode = 0; |
| |
| if (__raw_readl(DMA_BASE + DMA_DBTOSR) & (1 << i)) { |
| __raw_writel(1 << i, DMA_BASE + DMA_DBTOSR); |
| errcode |= IMX_DMA_ERR_BURST; |
| } |
| if (__raw_readl(DMA_BASE + DMA_DRTOSR) & (1 << i)) { |
| __raw_writel(1 << i, DMA_BASE + DMA_DRTOSR); |
| errcode |= IMX_DMA_ERR_REQUEST; |
| } |
| if (__raw_readl(DMA_BASE + DMA_DSESR) & (1 << i)) { |
| __raw_writel(1 << i, DMA_BASE + DMA_DSESR); |
| errcode |= IMX_DMA_ERR_TRANSFER; |
| } |
| if (__raw_readl(DMA_BASE + DMA_DBOSR) & (1 << i)) { |
| __raw_writel(1 << i, DMA_BASE + 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 = __raw_readl(DMA_BASE + 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; |
| __raw_writel(tmp, DMA_BASE + |
| DMA_CCR(chno)); |
| } else { |
| __raw_writel(tmp & ~CCR_CEN, DMA_BASE + |
| DMA_CCR(chno)); |
| tmp |= CCR_CEN; |
| } |
| |
| __raw_writel(tmp, DMA_BASE + 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; |
| } |
| } |
| |
| __raw_writel(0, DMA_BASE + 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; |
| |
| #ifdef CONFIG_ARCH_MX2 |
| dma_err_handler(irq, dev_id); |
| #endif |
| |
| disr = __raw_readl(DMA_BASE + DMA_DISR); |
| |
| pr_debug("imxdma: dma_irq_handler called, disr=0x%08x\n", |
| disr); |
| |
| __raw_writel(disr, DMA_BASE + 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; |
| |
| /* 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; |
| } |
| |
| #ifdef CONFIG_ARCH_MX2 |
| ret = request_irq(MXC_INT_DMACH0 + channel, dma_irq_handler, 0, "DMA", |
| NULL); |
| if (ret) { |
| printk(KERN_CRIT "Can't register IRQ %d for DMA channel %d\n", |
| MXC_INT_DMACH0 + channel, channel); |
| return ret; |
| } |
| init_timer(&imxdma->watchdog); |
| imxdma->watchdog.function = &imx_dma_watchdog; |
| imxdma->watchdog.data = channel; |
| #endif |
| |
| imxdma->name = name; |
| imxdma->irq_handler = NULL; |
| imxdma->err_handler = NULL; |
| imxdma->data = NULL; |
| imxdma->sg = NULL; |
| |
| local_irq_restore(flags); |
| return 0; |
| } |
| 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 */ |
| __raw_writel(__raw_readl(DMA_BASE + DMA_DIMR) | (1 << channel), |
| DMA_BASE + DMA_DIMR); |
| __raw_writel(__raw_readl(DMA_BASE + DMA_CCR(channel)) & ~CCR_CEN, |
| DMA_BASE + DMA_CCR(channel)); |
| imxdma->name = NULL; |
| |
| #ifdef CONFIG_ARCH_MX2 |
| free_irq(MXC_INT_DMACH0 + channel, NULL); |
| #endif |
| |
| 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 |
| * 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; |
| |
| dma_clk = clk_get(NULL, "dma_clk"); |
| clk_enable(dma_clk); |
| |
| /* reset DMA module */ |
| __raw_writel(DCR_DRST, DMA_BASE + DMA_DCR); |
| |
| #ifdef CONFIG_ARCH_MX1 |
| ret = request_irq(DMA_INT, dma_irq_handler, 0, "DMA", NULL); |
| if (ret) { |
| printk(KERN_CRIT "Wow! Can't register IRQ for DMA\n"); |
| return ret; |
| } |
| |
| ret = request_irq(DMA_ERR, dma_err_handler, 0, "DMA", NULL); |
| if (ret) { |
| printk(KERN_CRIT "Wow! Can't register ERRIRQ for DMA\n"); |
| free_irq(DMA_INT, NULL); |
| return ret; |
| } |
| #endif |
| /* enable DMA module */ |
| __raw_writel(DCR_DEN, DMA_BASE + DMA_DCR); |
| |
| /* clear all interrupts */ |
| __raw_writel((1 << IMX_DMA_CHANNELS) - 1, DMA_BASE + DMA_DISR); |
| |
| /* disable interrupts */ |
| __raw_writel((1 << IMX_DMA_CHANNELS) - 1, DMA_BASE + 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); |