diff options
30 files changed, 2541 insertions, 1011 deletions
diff --git a/Documentation/dmaengine.txt b/Documentation/dmaengine.txt index 5a0cb1ef616..94b7e0f96b3 100644 --- a/Documentation/dmaengine.txt +++ b/Documentation/dmaengine.txt @@ -10,87 +10,181 @@ NOTE: For DMA Engine usage in async_tx please see: Below is a guide to device driver writers on how to use the Slave-DMA API of the DMA Engine. This is applicable only for slave DMA usage only. -The slave DMA usage consists of following steps +The slave DMA usage consists of following steps: 1. Allocate a DMA slave channel 2. Set slave and controller specific parameters 3. Get a descriptor for transaction -4. Submit the transaction and wait for callback notification +4. Submit the transaction +5. Issue pending requests and wait for callback notification 1. Allocate a DMA slave channel -Channel allocation is slightly different in the slave DMA context, client -drivers typically need a channel from a particular DMA controller only and even -in some cases a specific channel is desired. To request a channel -dma_request_channel() API is used. - -Interface: -struct dma_chan *dma_request_channel(dma_cap_mask_t mask, - dma_filter_fn filter_fn, - void *filter_param); -where dma_filter_fn is defined as: -typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param); - -When the optional 'filter_fn' parameter is set to NULL dma_request_channel -simply returns the first channel that satisfies the capability mask. Otherwise, -when the mask parameter is insufficient for specifying the necessary channel, -the filter_fn routine can be used to disposition the available channels in the -system. The filter_fn routine is called once for each free channel in the -system. Upon seeing a suitable channel filter_fn returns DMA_ACK which flags -that channel to be the return value from dma_request_channel. A channel -allocated via this interface is exclusive to the caller, until -dma_release_channel() is called. + + Channel allocation is slightly different in the slave DMA context, + client drivers typically need a channel from a particular DMA + controller only and even in some cases a specific channel is desired. + To request a channel dma_request_channel() API is used. + + Interface: + struct dma_chan *dma_request_channel(dma_cap_mask_t mask, + dma_filter_fn filter_fn, + void *filter_param); + where dma_filter_fn is defined as: + typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param); + + The 'filter_fn' parameter is optional, but highly recommended for + slave and cyclic channels as they typically need to obtain a specific + DMA channel. + + When the optional 'filter_fn' parameter is NULL, dma_request_channel() + simply returns the first channel that satisfies the capability mask. + + Otherwise, the 'filter_fn' routine will be called once for each free + channel which has a capability in 'mask'. 'filter_fn' is expected to + return 'true' when the desired DMA channel is found. + + A channel allocated via this interface is exclusive to the caller, + until dma_release_channel() is called. 2. Set slave and controller specific parameters -Next step is always to pass some specific information to the DMA driver. Most of -the generic information which a slave DMA can use is in struct dma_slave_config. -It allows the clients to specify DMA direction, DMA addresses, bus widths, DMA -burst lengths etc. If some DMA controllers have more parameters to be sent then -they should try to embed struct dma_slave_config in their controller specific -structure. That gives flexibility to client to pass more parameters, if -required. - -Interface: -int dmaengine_slave_config(struct dma_chan *chan, - struct dma_slave_config *config) + + Next step is always to pass some specific information to the DMA + driver. Most of the generic information which a slave DMA can use + is in struct dma_slave_config. This allows the clients to specify + DMA direction, DMA addresses, bus widths, DMA burst lengths etc + for the peripheral. + + If some DMA controllers have more parameters to be sent then they + should try to embed struct dma_slave_config in their controller + specific structure. That gives flexibility to client to pass more + parameters, if required. + + Interface: + int dmaengine_slave_config(struct dma_chan *chan, + struct dma_slave_config *config) + + Please see the dma_slave_config structure definition in dmaengine.h + for a detailed explaination of the struct members. Please note + that the 'direction' member will be going away as it duplicates the + direction given in the prepare call. 3. Get a descriptor for transaction -For slave usage the various modes of slave transfers supported by the -DMA-engine are: -slave_sg - DMA a list of scatter gather buffers from/to a peripheral -dma_cyclic - Perform a cyclic DMA operation from/to a peripheral till the + + For slave usage the various modes of slave transfers supported by the + DMA-engine are: + + slave_sg - DMA a list of scatter gather buffers from/to a peripheral + dma_cyclic - Perform a cyclic DMA operation from/to a peripheral till the operation is explicitly stopped. -The non NULL return of this transfer API represents a "descriptor" for the given -transaction. - -Interface: -struct dma_async_tx_descriptor *(*chan->device->device_prep_dma_sg)( - struct dma_chan *chan, - struct scatterlist *dst_sg, unsigned int dst_nents, - struct scatterlist *src_sg, unsigned int src_nents, + + A non-NULL return of this transfer API represents a "descriptor" for + the given transaction. + + Interface: + struct dma_async_tx_descriptor *(*chan->device->device_prep_slave_sg)( + struct dma_chan *chan, struct scatterlist *sgl, + unsigned int sg_len, enum dma_data_direction direction, unsigned long flags); -struct dma_async_tx_descriptor *(*chan->device->device_prep_dma_cyclic)( + + struct dma_async_tx_descriptor *(*chan->device->device_prep_dma_cyclic)( struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, size_t period_len, enum dma_data_direction direction); -4. Submit the transaction and wait for callback notification -To schedule the transaction to be scheduled by dma device, the "descriptor" -returned in above (3) needs to be submitted. -To tell the dma driver that a transaction is ready to be serviced, the -descriptor->submit() callback needs to be invoked. This chains the descriptor to -the pending queue. -The transactions in the pending queue can be activated by calling the -issue_pending API. If channel is idle then the first transaction in queue is -started and subsequent ones queued up. -On completion of the DMA operation the next in queue is submitted and a tasklet -triggered. The tasklet would then call the client driver completion callback -routine for notification, if set. -Interface: -void dma_async_issue_pending(struct dma_chan *chan); - -============================================================================== - -Additional usage notes for dma driver writers -1/ Although DMA engine specifies that completion callback routines cannot submit -any new operations, but typically for slave DMA subsequent transaction may not -be available for submit prior to callback routine being called. This requirement -is not a requirement for DMA-slave devices. But they should take care to drop -the spin-lock they might be holding before calling the callback routine + The peripheral driver is expected to have mapped the scatterlist for + the DMA operation prior to calling device_prep_slave_sg, and must + keep the scatterlist mapped until the DMA operation has completed. + The scatterlist must be mapped using the DMA struct device. So, + normal setup should look like this: + + nr_sg = dma_map_sg(chan->device->dev, sgl, sg_len); + if (nr_sg == 0) + /* error */ + + desc = chan->device->device_prep_slave_sg(chan, sgl, nr_sg, + direction, flags); + + Once a descriptor has been obtained, the callback information can be + added and the descriptor must then be submitted. Some DMA engine + drivers may hold a spinlock between a successful preparation and + submission so it is important that these two operations are closely + paired. + + Note: + Although the async_tx API specifies that completion callback + routines cannot submit any new operations, this is not the + case for slave/cyclic DMA. + + For slave DMA, the subsequent transaction may not be available + for submission prior to callback function being invoked, so + slave DMA callbacks are permitted to prepare and submit a new + transaction. + + For cyclic DMA, a callback function may wish to terminate the + DMA via dmaengine_terminate_all(). + + Therefore, it is important that DMA engine drivers drop any + locks before calling the callback function which may cause a + deadlock. + + Note that callbacks will always be invoked from the DMA + engines tasklet, never from interrupt context. + +4. Submit the transaction + + Once the descriptor has been prepared and the callback information + added, it must be placed on the DMA engine drivers pending queue. + + Interface: + dma_cookie_t dmaengine_submit(struct dma_async_tx_descriptor *desc) + + This returns a cookie can be used to check the progress of DMA engine + activity via other DMA engine calls not covered in this document. + + dmaengine_submit() will not start the DMA operation, it merely adds + it to the pending queue. For this, see step 5, dma_async_issue_pending. + +5. Issue pending DMA requests and wait for callback notification + + The transactions in the pending queue can be activated by calling the + issue_pending API. If channel is idle then the first transaction in + queue is started and subsequent ones queued up. + + On completion of each DMA operation, the next in queue is started and + a tasklet triggered. The tasklet will then call the client driver + completion callback routine for notification, if set. + + Interface: + void dma_async_issue_pending(struct dma_chan *chan); + +Further APIs: + +1. int dmaengine_terminate_all(struct dma_chan *chan) + + This causes all activity for the DMA channel to be stopped, and may + discard data in the DMA FIFO which hasn't been fully transferred. + No callback functions will be called for any incomplete transfers. + +2. int dmaengine_pause(struct dma_chan *chan) + + This pauses activity on the DMA channel without data loss. + +3. int dmaengine_resume(struct dma_chan *chan) + + Resume a previously paused DMA channel. It is invalid to resume a + channel which is not currently paused. + +4. enum dma_status dma_async_is_tx_complete(struct dma_chan *chan, + dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used) + + This can be used to check the status of the channel. Please see + the documentation in include/linux/dmaengine.h for a more complete + description of this API. + + This can be used in conjunction with dma_async_is_complete() and + the cookie returned from 'descriptor->submit()' to check for + completion of a specific DMA transaction. + + Note: + Not all DMA engine drivers can return reliable information for + a running DMA channel. It is recommended that DMA engine users + pause or stop (via dmaengine_terminate_all) the channel before + using this API. diff --git a/Documentation/spi/ep93xx_spi b/Documentation/spi/ep93xx_spi index 6325f5b4863..d8eb01c15db 100644 --- a/Documentation/spi/ep93xx_spi +++ b/Documentation/spi/ep93xx_spi @@ -88,6 +88,16 @@ static void __init ts72xx_init_machine(void) ARRAY_SIZE(ts72xx_spi_devices)); } +The driver can use DMA for the transfers also. In this case ts72xx_spi_info +becomes: + +static struct ep93xx_spi_info ts72xx_spi_info = { + .num_chipselect = ARRAY_SIZE(ts72xx_spi_devices), + .use_dma = true; +}; + +Note that CONFIG_EP93XX_DMA should be enabled as well. + Thanks to ========= Martin Guy, H. Hartley Sweeten and others who helped me during development of diff --git a/arch/arm/mach-ep93xx/Makefile b/arch/arm/mach-ep93xx/Makefile index 33ee2c863d1..21e721ab737 100644 --- a/arch/arm/mach-ep93xx/Makefile +++ b/arch/arm/mach-ep93xx/Makefile @@ -1,11 +1,13 @@ # # Makefile for the linux kernel. # -obj-y := core.o clock.o dma-m2p.o gpio.o +obj-y := core.o clock.o gpio.o obj-m := obj-n := obj- := +obj-$(CONFIG_EP93XX_DMA) += dma.o + obj-$(CONFIG_MACH_ADSSPHERE) += adssphere.o obj-$(CONFIG_MACH_EDB93XX) += edb93xx.o obj-$(CONFIG_MACH_GESBC9312) += gesbc9312.o diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c index 6659a0d137a..dd87a827223 100644 --- a/arch/arm/mach-ep93xx/core.c +++ b/arch/arm/mach-ep93xx/core.c @@ -492,11 +492,15 @@ static struct resource ep93xx_spi_resources[] = { }, }; +static u64 ep93xx_spi_dma_mask = DMA_BIT_MASK(32); + static struct platform_device ep93xx_spi_device = { .name = "ep93xx-spi", .id = 0, .dev = { - .platform_data = &ep93xx_spi_master_data, + .platform_data = &ep93xx_spi_master_data, + .coherent_dma_mask = DMA_BIT_MASK(32), + .dma_mask = &ep93xx_spi_dma_mask, }, .num_resources = ARRAY_SIZE(ep93xx_spi_resources), .resource = ep93xx_spi_resources, diff --git a/arch/arm/mach-ep93xx/dma-m2p.c b/arch/arm/mach-ep93xx/dma-m2p.c deleted file mode 100644 index a696d354b1f..00000000000 --- a/arch/arm/mach-ep93xx/dma-m2p.c +++ /dev/null @@ -1,411 +0,0 @@ -/* - * arch/arm/mach-ep93xx/dma-m2p.c - * M2P DMA handling for Cirrus EP93xx chips. - * - * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> - * Copyright (C) 2006 Applied Data Systems - * - * Copyright (C) 2009 Ryan Mallon <ryan@bluewatersys.com> - * - * 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. - */ - -/* - * On the EP93xx chip the following peripherals my be allocated to the 10 - * Memory to Internal Peripheral (M2P) channels (5 transmit + 5 receive). - * - * I2S contains 3 Tx and 3 Rx DMA Channels - * AAC contains 3 Tx and 3 Rx DMA Channels - * UART1 contains 1 Tx and 1 Rx DMA Channels - * UART2 contains 1 Tx and 1 Rx DMA Channels - * UART3 contains 1 Tx and 1 Rx DMA Channels - * IrDA contains 1 Tx and 1 Rx DMA Channels - * - * SSP and IDE use the Memory to Memory (M2M) channels and are not covered - * with this implementation. - */ - -#define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt - -#include <linux/kernel.h> -#include <linux/clk.h> -#include <linux/err.h> -#include <linux/interrupt.h> -#include <linux/module.h> -#include <linux/io.h> - -#include <mach/dma.h> -#include <mach/hardware.h> - -#define M2P_CONTROL 0x00 -#define M2P_CONTROL_STALL_IRQ_EN (1 << 0) -#define M2P_CONTROL_NFB_IRQ_EN (1 << 1) -#define M2P_CONTROL_ERROR_IRQ_EN (1 << 3) -#define M2P_CONTROL_ENABLE (1 << 4) -#define M2P_INTERRUPT 0x04 -#define M2P_INTERRUPT_STALL (1 << 0) -#define M2P_INTERRUPT_NFB (1 << 1) -#define M2P_INTERRUPT_ERROR (1 << 3) -#define M2P_PPALLOC 0x08 -#define M2P_STATUS 0x0c -#define M2P_REMAIN 0x14 -#define M2P_MAXCNT0 0x20 -#define M2P_BASE0 0x24 -#define M2P_MAXCNT1 0x30 -#define M2P_BASE1 0x34 - -#define STATE_IDLE 0 /* Channel is inactive. */ -#define STATE_STALL 1 /* Channel is active, no buffers pending. */ -#define STATE_ON 2 /* Channel is active, one buffer pending. */ -#define STATE_NEXT 3 /* Channel is active, two buffers pending. */ - -struct m2p_channel { - char *name; - void __iomem *base; - int irq; - - struct clk *clk; - spinlock_t lock; - - void *client; - unsigned next_slot:1; - struct ep93xx_dma_buffer *buffer_xfer; - struct ep93xx_dma_buffer *buffer_next; - struct list_head buffers_pending; -}; - -static struct m2p_channel m2p_rx[] = { - {"m2p1", EP93XX_DMA_BASE + 0x0040, IRQ_EP93XX_DMAM2P1}, - {"m2p3", EP93XX_DMA_BASE + 0x00c0, IRQ_EP93XX_DMAM2P3}, - {"m2p5", EP93XX_DMA_BASE + 0x0200, IRQ_EP93XX_DMAM2P5}, - {"m2p7", EP93XX_DMA_BASE + 0x0280, IRQ_EP93XX_DMAM2P7}, - {"m2p9", EP93XX_DMA_BASE + 0x0300, IRQ_EP93XX_DMAM2P9}, - {NULL}, -}; - -static struct m2p_channel m2p_tx[] = { - {"m2p0", EP93XX_DMA_BASE + 0x0000, IRQ_EP93XX_DMAM2P0}, - {"m2p2", EP93XX_DMA_BASE + 0x0080, IRQ_EP93XX_DMAM2P2}, - {"m2p4", EP93XX_DMA_BASE + 0x0240, IRQ_EP93XX_DMAM2P4}, - {"m2p6", EP93XX_DMA_BASE + 0x02c0, IRQ_EP93XX_DMAM2P6}, - {"m2p8", EP93XX_DMA_BASE + 0x0340, IRQ_EP93XX_DMAM2P8}, - {NULL}, -}; - -static void feed_buf(struct m2p_channel *ch, struct ep93xx_dma_buffer *buf) -{ - if (ch->next_slot == 0) { - writel(buf->size, ch->base + M2P_MAXCNT0); - writel(buf->bus_addr, ch->base + M2P_BASE0); - } else { - writel(buf->size, ch->base + M2P_MAXCNT1); - writel(buf->bus_addr, ch->base + M2P_BASE1); - } - ch->next_slot ^= 1; -} - -static void choose_buffer_xfer(struct m2p_channel *ch) -{ - struct ep93xx_dma_buffer *buf; - - ch->buffer_xfer = NULL; - if (!list_empty(&ch->buffers_pending)) { - buf = list_entry(ch->buffers_pending.next, - struct ep93xx_dma_buffer, list); - list_del(&buf->list); - feed_buf(ch, buf); - ch->buffer_xfer = buf; - } -} - -static void choose_buffer_next(struct m2p_channel *ch) -{ - struct ep93xx_dma_buffer *buf; - - ch->buffer_next = NULL; - if (!list_empty(&ch->buffers_pending)) { - buf = list_entry(ch->buffers_pending.next, - struct ep93xx_dma_buffer, list); - list_del(&buf->list); - feed_buf(ch, buf); - ch->buffer_next = buf; - } -} - -static inline void m2p_set_control(struct m2p_channel *ch, u32 v) -{ - /* - * The control register must be read immediately after being written so - * that the internal state machine is correctly updated. See the ep93xx - * users' guide for details. - */ - writel(v, ch->base + M2P_CONTROL); - readl(ch->base + M2P_CONTROL); -} - -static inline int m2p_channel_state(struct m2p_channel *ch) -{ - return (readl(ch->base + M2P_STATUS) >> 4) & 0x3; -} - -static irqreturn_t m2p_irq(int irq, void *dev_id) -{ - struct m2p_channel *ch = dev_id; - struct ep93xx_dma_m2p_client *cl; - u32 irq_status, v; - int error = 0; - - cl = ch->client; - - spin_lock(&ch->lock); - irq_status = readl(ch->base + M2P_INTERRUPT); - - if (irq_status & M2P_INTERRUPT_ERROR) { - writel(M2P_INTERRUPT_ERROR, ch->base + M2P_INTERRUPT); - error = 1; - } - - if ((irq_status & (M2P_INTERRUPT_STALL | M2P_INTERRUPT_NFB)) == 0) { - spin_unlock(&ch->lock); - return IRQ_NONE; - } - - switch (m2p_channel_state(ch)) { - case STATE_IDLE: - pr_crit("dma interrupt without a dma buffer\n"); - BUG(); - break; - - case STATE_STALL: - cl->buffer_finished(cl->cookie, ch->buffer_xfer, 0, error); - if (ch->buffer_next != NULL) { - cl->buffer_finished(cl->cookie, ch->buffer_next, - 0, error); - } - choose_buffer_xfer(ch); - choose_buffer_next(ch); - if (ch->buffer_xfer != NULL) - cl->buffer_started(cl->cookie, ch->buffer_xfer); - break; - - case STATE_ON: - cl->buffer_finished(cl->cookie, ch->buffer_xfer, 0, error); - ch->buffer_xfer = ch->buffer_next; - choose_buffer_next(ch); - cl->buffer_started(cl->cookie, ch->buffer_xfer); - break; - - case STATE_NEXT: - pr_crit("dma interrupt while next\n"); - BUG(); - break; - } - - v = readl(ch->base + M2P_CONTROL) & ~(M2P_CONTROL_STALL_IRQ_EN | - M2P_CONTROL_NFB_IRQ_EN); - if (ch->buffer_xfer != NULL) - v |= M2P_CONTROL_STALL_IRQ_EN; - if (ch->buffer_next != NULL) - v |= M2P_CONTROL_NFB_IRQ_EN; - m2p_set_control(ch, v); - - spin_unlock(&ch->lock); - return IRQ_HANDLED; -} - -static struct m2p_channel *find_free_channel(struct ep93xx_dma_m2p_client *cl) -{ - struct m2p_channel *ch; - int i; - - if (cl->flags & EP93XX_DMA_M2P_RX) - ch = m2p_rx; - else - ch = m2p_tx; - - for (i = 0; ch[i].base; i++) { - struct ep93xx_dma_m2p_client *client; - - client = ch[i].client; - if (client != NULL) { - int port; - - port = cl->flags & EP93XX_DMA_M2P_PORT_MASK; - if (port == (client->flags & - EP93XX_DMA_M2P_PORT_MASK)) { - pr_warning("DMA channel already used by %s\n", - cl->name ? : "unknown client"); - return ERR_PTR(-EBUSY); - } - } - } - - for (i = 0; ch[i].base; i++) { - if (ch[i].client == NULL) - return ch + i; - } - - pr_warning("No free DMA channel for %s\n", - cl->name ? : "unknown client"); - return ERR_PTR(-ENODEV); -} - -static void channel_enable(struct m2p_channel *ch) -{ - struct ep93xx_dma_m2p_client *cl = ch->client; - u32 v; - - clk_enable(ch->clk); - - v = cl->flags & EP93XX_DMA_M2P_PORT_MASK; - writel(v, ch->base + M2P_PPALLOC); - - v = cl->flags & EP93XX_DMA_M2P_ERROR_MASK; - v |= M2P_CONTROL_ENABLE | M2P_CONTROL_ERROR_IRQ_EN; - m2p_set_control(ch, v); -} - -static void channel_disable(struct m2p_channel *ch) -{ - u32 v; - - v = readl(ch->base + M2P_CONTROL); - v &= ~(M2P_CONTROL_STALL_IRQ_EN | M2P_CONTROL_NFB_IRQ_EN); - m2p_set_control(ch, v); - - while (m2p_channel_state(ch) >= STATE_ON) - cpu_relax(); - - m2p_set_control(ch, 0x0); - - while (m2p_channel_state(ch) == STATE_STALL) - cpu_relax(); - - clk_disable(ch->clk); -} - -int ep93xx_dma_m2p_client_register(struct ep93xx_dma_m2p_client *cl) -{ - struct m2p_channel *ch; - int err; - - ch = find_free_channel(cl); - if (IS_ERR(ch)) - return PTR_ERR(ch); - - err = request_irq(ch->irq, m2p_irq, 0, cl->name ? : "dma-m2p", ch); - if (err) - return err; - - ch->client = cl; - ch->next_slot = 0; - ch->buffer_xfer = NULL; - ch->buffer_next = NULL; - INIT_LIST_HEAD(&ch->buffers_pending); - - cl->channel = ch; - - channel_enable(ch); - - return 0; -} -EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_client_register); - -void ep93xx_dma_m2p_client_unregister(struct ep93xx_dma_m2p_client *cl) -{ - struct m2p_channel *ch = cl->channel; - - channel_disable(ch); - free_irq(ch->irq, ch); - ch->client = NULL; -} -EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_client_unregister); - -void ep93xx_dma_m2p_submit(struct ep93xx_dma_m2p_client *cl, - struct ep93xx_dma_buffer *buf) -{ - struct m2p_channel *ch = cl->channel; - unsigned long flags; - u32 v; - - spin_lock_irqsave(&ch->lock, flags); - v = readl(ch->base + M2P_CONTROL); - if (ch->buffer_xfer == NULL) { - ch->buffer_xfer = buf; - feed_buf(ch, buf); - cl->buffer_started(cl->cookie, buf); - - v |= M2P_CONTROL_STALL_IRQ_EN; - m2p_set_control(ch, v); - - } else if (ch->buffer_next == NULL) { - ch->buffer_next = buf; - feed_buf(ch, buf); - - v |= M2P_CONTROL_NFB_IRQ_EN; - m2p_set_control(ch, v); - } else { - list_add_tail(&buf->list, &ch->buffers_pending); - } - spin_unlock_irqrestore(&ch->lock, flags); -} -EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_submit); - -void ep93xx_dma_m2p_submit_recursive(struct ep93xx_dma_m2p_client *cl, - struct ep93xx_dma_buffer *buf) -{ - struct m2p_channel *ch = cl->channel; - - list_add_tail(&buf->list, &ch->buffers_pending); -} -EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_submit_recursive); - -void ep93xx_dma_m2p_flush(struct ep93xx_dma_m2p_client *cl) -{ - struct m2p_channel *ch = cl->channel; - - channel_disable(ch); - ch->next_slot = 0; - ch->buffer_xfer = NULL; - ch->buffer_next = NULL; - INIT_LIST_HEAD(&ch->buffers_pending); - channel_enable(ch); -} -EXPORT_SYMBOL_GPL(ep93xx_dma_m2p_flush); - -static int init_channel(struct m2p_channel *ch) -{ - ch->clk = clk_get(NULL, ch->name); - if (IS_ERR(ch->clk)) - return PTR_ERR(ch->clk); - - spin_lock_init(&ch->lock); - ch->client = NULL; - - return 0; -} - -static int __init ep93xx_dma_m2p_init(void) -{ - int i; - int ret; - - for (i = 0; m2p_rx[i].base; i++) { - ret = init_channel(m2p_rx + i); - if (ret) - return ret; - } - - for (i = 0; m2p_tx[i].base; i++) { - ret = init_channel(m2p_tx + i); - if (ret) - return ret; - } - - pr_info("M2P DMA subsystem initialized\n"); - return 0; -} -arch_initcall(ep93xx_dma_m2p_init); diff --git a/arch/arm/mach-ep93xx/dma.c b/arch/arm/mach-ep93xx/dma.c new file mode 100644 index 00000000000..5a257088125 --- /dev/null +++ b/arch/arm/mach-ep93xx/dma.c @@ -0,0 +1,108 @@ +/* + * arch/arm/mach-ep93xx/dma.c + * + * Platform support code for the EP93xx dmaengine driver. + * + * Copyright (C) 2011 Mika Westerberg + * + * This work is based on the original dma-m2p implementation with + * following copyrights: + * + * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> + * Copyright (C) 2006 Applied Data Systems + * Copyright (C) 2009 Ryan Mallon <rmallon@gmail.com> + * + * 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. + */ + +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> + +#include <mach/dma.h> +#include <mach/hardware.h> + +#define DMA_CHANNEL(_name, _base, _irq) \ + { .name = (_name), .base = (_base), .irq = (_irq) } + +/* + * DMA M2P channels. + * + * On the EP93xx chip the following peripherals my be allocated to the 10 + * Memory to Internal Peripheral (M2P) channels (5 transmit + 5 receive). + * + * I2S contains 3 Tx and 3 Rx DMA Channels + * AAC contains 3 Tx and 3 Rx DMA Channels + * UART1 contains 1 Tx and 1 Rx DMA Channels + * UART2 contains 1 Tx and 1 Rx DMA Channels + * UART3 contains 1 Tx and 1 Rx DMA Channels + * IrDA contains 1 Tx and 1 Rx DMA Channels + * + * Registers are mapped statically in ep93xx_map_io(). + */ +static struct ep93xx_dma_chan_data ep93xx_dma_m2p_channels[] = { + DMA_CHANNEL("m2p0", EP93XX_DMA_BASE + 0x0000, IRQ_EP93XX_DMAM2P0), + DMA_CHANNEL("m2p1", EP93XX_DMA_BASE + 0x0040, IRQ_EP93XX_DMAM2P1), + DMA_CHANNEL("m2p2", EP93XX_DMA_BASE + 0x0080, IRQ_EP93XX_DMAM2P2), + DMA_CHANNEL("m2p3", EP93XX_DMA_BASE + 0x00c0, IRQ_EP93XX_DMAM2P3), + DMA_CHANNEL("m2p4", EP93XX_DMA_BASE + 0x0240, IRQ_EP93XX_DMAM2P4), + DMA_CHANNEL("m2p5", EP93XX_DMA_BASE + 0x0200, IRQ_EP93XX_DMAM2P5), + DMA_CHANNEL("m2p6", EP93XX_DMA_BASE + 0x02c0, IRQ_EP93XX_DMAM2P6), + DMA_CHANNEL("m2p7", EP93XX_DMA_BASE + 0x0280, IRQ_EP93XX_DMAM2P7), + DMA_CHANNEL("m2p8", EP93XX_DMA_BASE + 0x0340, IRQ_EP93XX_DMAM2P8), + DMA_CHANNEL("m2p9", EP93XX_DMA_BASE + 0x0300, IRQ_EP93XX_DMAM2P9), +}; + +static struct ep93xx_dma_platform_data ep93xx_dma_m2p_data = { + .channels = ep93xx_dma_m2p_channels, + .num_channels = ARRAY_SIZE(ep93xx_dma_m2p_channels), +}; + +static struct platform_device ep93xx_dma_m2p_device = { + .name = "ep93xx-dma-m2p", + .id = -1, + .dev = { + .platform_data = &ep93xx_dma_m2p_data, + }, +}; + +/* + * DMA M2M channels. + * + * There are 2 M2M channels which support memcpy/memset and in addition simple + * hardware requests from/to SSP and IDE. We do not implement an external + * hardware requests. + * + * Registers are mapped statically in ep93xx_map_io(). + */ +static struct ep93xx_dma_chan_data ep93xx_dma_m2m_channels[] = { + DMA_CHANNEL("m2m0", EP93XX_DMA_BASE + 0x0100, IRQ_EP93XX_DMAM2M0), + DMA_CHANNEL("m2m1", EP93XX_DMA_BASE + 0x0140, IRQ_EP93XX_DMAM2M1), +}; + +static struct ep93xx_dma_platform_data ep93xx_dma_m2m_data = { + .channels = ep93xx_dma_m2m_channels, + .num_channels = ARRAY_SIZE(ep93xx_dma_m2m_channels), +}; + +static struct platform_device ep93xx_dma_m2m_device = { + .name = "ep93xx-dma-m2m", + .id = -1, + .dev = { + .platform_data = &ep93xx_dma_m2m_data, + }, +}; + +static int __init ep93xx_dma_init(void) +{ + platform_device_register(&ep93xx_dma_m2p_device); + platform_device_register(&ep93xx_dma_m2m_device); + return 0; +} +arch_initcall(ep93xx_dma_init); diff --git a/arch/arm/mach-ep93xx/include/mach/dma.h b/arch/arm/mach-ep93xx/include/mach/dma.h index 5e31b2b25da..46d4d876e6f 100644 --- a/arch/arm/mach-ep93xx/include/mach/dma.h +++ b/arch/arm/mach-ep93xx/include/mach/dma.h @@ -1,149 +1,93 @@ -/** - * DOC: EP93xx DMA M2P memory to peripheral and peripheral to memory engine - * - * The EP93xx DMA M2P subsystem handles DMA transfers between memory and - * peripherals. DMA M2P channels are available for audio, UARTs and IrDA. - * See chapter 10 of the EP93xx users guide for full details on the DMA M2P |