| /* |
| * Freescale MPC85xx, MPC83xx DMA Engine support |
| * |
| * Copyright (C) 2007-2010 Freescale Semiconductor, Inc. All rights reserved. |
| * |
| * Author: |
| * Zhang Wei <wei.zhang@freescale.com>, Jul 2007 |
| * Ebony Zhu <ebony.zhu@freescale.com>, May 2007 |
| * |
| * Description: |
| * DMA engine driver for Freescale MPC8540 DMA controller, which is |
| * also fit for MPC8560, MPC8555, MPC8548, MPC8641, and etc. |
| * The support for MPC8349 DMA controller is also added. |
| * |
| * This driver instructs the DMA controller to issue the PCI Read Multiple |
| * command for PCI read operations, instead of using the default PCI Read Line |
| * command. Please be aware that this setting may result in read pre-fetching |
| * on some platforms. |
| * |
| * This 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/init.h> |
| #include <linux/module.h> |
| #include <linux/pci.h> |
| #include <linux/slab.h> |
| #include <linux/interrupt.h> |
| #include <linux/dmaengine.h> |
| #include <linux/delay.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/dmapool.h> |
| #include <linux/of_platform.h> |
| |
| #include "dmaengine.h" |
| #include "fsldma.h" |
| |
| #define chan_dbg(chan, fmt, arg...) \ |
| dev_dbg(chan->dev, "%s: " fmt, chan->name, ##arg) |
| #define chan_err(chan, fmt, arg...) \ |
| dev_err(chan->dev, "%s: " fmt, chan->name, ##arg) |
| |
| static const char msg_ld_oom[] = "No free memory for link descriptor"; |
| |
| /* |
| * Register Helpers |
| */ |
| |
| static void set_sr(struct fsldma_chan *chan, u32 val) |
| { |
| DMA_OUT(chan, &chan->regs->sr, val, 32); |
| } |
| |
| static u32 get_sr(struct fsldma_chan *chan) |
| { |
| return DMA_IN(chan, &chan->regs->sr, 32); |
| } |
| |
| static void set_cdar(struct fsldma_chan *chan, dma_addr_t addr) |
| { |
| DMA_OUT(chan, &chan->regs->cdar, addr | FSL_DMA_SNEN, 64); |
| } |
| |
| static dma_addr_t get_cdar(struct fsldma_chan *chan) |
| { |
| return DMA_IN(chan, &chan->regs->cdar, 64) & ~FSL_DMA_SNEN; |
| } |
| |
| static u32 get_bcr(struct fsldma_chan *chan) |
| { |
| return DMA_IN(chan, &chan->regs->bcr, 32); |
| } |
| |
| /* |
| * Descriptor Helpers |
| */ |
| |
| static void set_desc_cnt(struct fsldma_chan *chan, |
| struct fsl_dma_ld_hw *hw, u32 count) |
| { |
| hw->count = CPU_TO_DMA(chan, count, 32); |
| } |
| |
| static u32 get_desc_cnt(struct fsldma_chan *chan, struct fsl_desc_sw *desc) |
| { |
| return DMA_TO_CPU(chan, desc->hw.count, 32); |
| } |
| |
| static void set_desc_src(struct fsldma_chan *chan, |
| struct fsl_dma_ld_hw *hw, dma_addr_t src) |
| { |
| u64 snoop_bits; |
| |
| snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) |
| ? ((u64)FSL_DMA_SATR_SREADTYPE_SNOOP_READ << 32) : 0; |
| hw->src_addr = CPU_TO_DMA(chan, snoop_bits | src, 64); |
| } |
| |
| static dma_addr_t get_desc_src(struct fsldma_chan *chan, |
| struct fsl_desc_sw *desc) |
| { |
| u64 snoop_bits; |
| |
| snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) |
| ? ((u64)FSL_DMA_SATR_SREADTYPE_SNOOP_READ << 32) : 0; |
| return DMA_TO_CPU(chan, desc->hw.src_addr, 64) & ~snoop_bits; |
| } |
| |
| static void set_desc_dst(struct fsldma_chan *chan, |
| struct fsl_dma_ld_hw *hw, dma_addr_t dst) |
| { |
| u64 snoop_bits; |
| |
| snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) |
| ? ((u64)FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE << 32) : 0; |
| hw->dst_addr = CPU_TO_DMA(chan, snoop_bits | dst, 64); |
| } |
| |
| static dma_addr_t get_desc_dst(struct fsldma_chan *chan, |
| struct fsl_desc_sw *desc) |
| { |
| u64 snoop_bits; |
| |
| snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) |
| ? ((u64)FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE << 32) : 0; |
| return DMA_TO_CPU(chan, desc->hw.dst_addr, 64) & ~snoop_bits; |
| } |
| |
| static void set_desc_next(struct fsldma_chan *chan, |
| struct fsl_dma_ld_hw *hw, dma_addr_t next) |
| { |
| u64 snoop_bits; |
| |
| snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX) |
| ? FSL_DMA_SNEN : 0; |
| hw->next_ln_addr = CPU_TO_DMA(chan, snoop_bits | next, 64); |
| } |
| |
| static void set_ld_eol(struct fsldma_chan *chan, struct fsl_desc_sw *desc) |
| { |
| u64 snoop_bits; |
| |
| snoop_bits = ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX) |
| ? FSL_DMA_SNEN : 0; |
| |
| desc->hw.next_ln_addr = CPU_TO_DMA(chan, |
| DMA_TO_CPU(chan, desc->hw.next_ln_addr, 64) | FSL_DMA_EOL |
| | snoop_bits, 64); |
| } |
| |
| /* |
| * DMA Engine Hardware Control Helpers |
| */ |
| |
| static void dma_init(struct fsldma_chan *chan) |
| { |
| /* Reset the channel */ |
| DMA_OUT(chan, &chan->regs->mr, 0, 32); |
| |
| switch (chan->feature & FSL_DMA_IP_MASK) { |
| case FSL_DMA_IP_85XX: |
| /* Set the channel to below modes: |
| * EIE - Error interrupt enable |
| * EOLNIE - End of links interrupt enable |
| * BWC - Bandwidth sharing among channels |
| */ |
| DMA_OUT(chan, &chan->regs->mr, FSL_DMA_MR_BWC |
| | FSL_DMA_MR_EIE | FSL_DMA_MR_EOLNIE, 32); |
| break; |
| case FSL_DMA_IP_83XX: |
| /* Set the channel to below modes: |
| * EOTIE - End-of-transfer interrupt enable |
| * PRC_RM - PCI read multiple |
| */ |
| DMA_OUT(chan, &chan->regs->mr, FSL_DMA_MR_EOTIE |
| | FSL_DMA_MR_PRC_RM, 32); |
| break; |
| } |
| } |
| |
| static int dma_is_idle(struct fsldma_chan *chan) |
| { |
| u32 sr = get_sr(chan); |
| return (!(sr & FSL_DMA_SR_CB)) || (sr & FSL_DMA_SR_CH); |
| } |
| |
| /* |
| * Start the DMA controller |
| * |
| * Preconditions: |
| * - the CDAR register must point to the start descriptor |
| * - the MRn[CS] bit must be cleared |
| */ |
| static void dma_start(struct fsldma_chan *chan) |
| { |
| u32 mode; |
| |
| mode = DMA_IN(chan, &chan->regs->mr, 32); |
| |
| if (chan->feature & FSL_DMA_CHAN_PAUSE_EXT) { |
| DMA_OUT(chan, &chan->regs->bcr, 0, 32); |
| mode |= FSL_DMA_MR_EMP_EN; |
| } else { |
| mode &= ~FSL_DMA_MR_EMP_EN; |
| } |
| |
| if (chan->feature & FSL_DMA_CHAN_START_EXT) { |
| mode |= FSL_DMA_MR_EMS_EN; |
| } else { |
| mode &= ~FSL_DMA_MR_EMS_EN; |
| mode |= FSL_DMA_MR_CS; |
| } |
| |
| DMA_OUT(chan, &chan->regs->mr, mode, 32); |
| } |
| |
| static void dma_halt(struct fsldma_chan *chan) |
| { |
| u32 mode; |
| int i; |
| |
| /* read the mode register */ |
| mode = DMA_IN(chan, &chan->regs->mr, 32); |
| |
| /* |
| * The 85xx controller supports channel abort, which will stop |
| * the current transfer. On 83xx, this bit is the transfer error |
| * mask bit, which should not be changed. |
| */ |
| if ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) { |
| mode |= FSL_DMA_MR_CA; |
| DMA_OUT(chan, &chan->regs->mr, mode, 32); |
| |
| mode &= ~FSL_DMA_MR_CA; |
| } |
| |
| /* stop the DMA controller */ |
| mode &= ~(FSL_DMA_MR_CS | FSL_DMA_MR_EMS_EN); |
| DMA_OUT(chan, &chan->regs->mr, mode, 32); |
| |
| /* wait for the DMA controller to become idle */ |
| for (i = 0; i < 100; i++) { |
| if (dma_is_idle(chan)) |
| return; |
| |
| udelay(10); |
| } |
| |
| if (!dma_is_idle(chan)) |
| chan_err(chan, "DMA halt timeout!\n"); |
| } |
| |
| /** |
| * fsl_chan_set_src_loop_size - Set source address hold transfer size |
| * @chan : Freescale DMA channel |
| * @size : Address loop size, 0 for disable loop |
| * |
| * The set source address hold transfer size. The source |
| * address hold or loop transfer size is when the DMA transfer |
| * data from source address (SA), if the loop size is 4, the DMA will |
| * read data from SA, SA + 1, SA + 2, SA + 3, then loop back to SA, |
| * SA + 1 ... and so on. |
| */ |
| static void fsl_chan_set_src_loop_size(struct fsldma_chan *chan, int size) |
| { |
| u32 mode; |
| |
| mode = DMA_IN(chan, &chan->regs->mr, 32); |
| |
| switch (size) { |
| case 0: |
| mode &= ~FSL_DMA_MR_SAHE; |
| break; |
| case 1: |
| case 2: |
| case 4: |
| case 8: |
| mode |= FSL_DMA_MR_SAHE | (__ilog2(size) << 14); |
| break; |
| } |
| |
| DMA_OUT(chan, &chan->regs->mr, mode, 32); |
| } |
| |
| /** |
| * fsl_chan_set_dst_loop_size - Set destination address hold transfer size |
| * @chan : Freescale DMA channel |
| * @size : Address loop size, 0 for disable loop |
| * |
| * The set destination address hold transfer size. The destination |
| * address hold or loop transfer size is when the DMA transfer |
| * data to destination address (TA), if the loop size is 4, the DMA will |
| * write data to TA, TA + 1, TA + 2, TA + 3, then loop back to TA, |
| * TA + 1 ... and so on. |
| */ |
| static void fsl_chan_set_dst_loop_size(struct fsldma_chan *chan, int size) |
| { |
| u32 mode; |
| |
| mode = DMA_IN(chan, &chan->regs->mr, 32); |
| |
| switch (size) { |
| case 0: |
| mode &= ~FSL_DMA_MR_DAHE; |
| break; |
| case 1: |
| case 2: |
| case 4: |
| case 8: |
| mode |= FSL_DMA_MR_DAHE | (__ilog2(size) << 16); |
| break; |
| } |
| |
| DMA_OUT(chan, &chan->regs->mr, mode, 32); |
| } |
| |
| /** |
| * fsl_chan_set_request_count - Set DMA Request Count for external control |
| * @chan : Freescale DMA channel |
| * @size : Number of bytes to transfer in a single request |
| * |
| * The Freescale DMA channel can be controlled by the external signal DREQ#. |
| * The DMA request count is how many bytes are allowed to transfer before |
| * pausing the channel, after which a new assertion of DREQ# resumes channel |
| * operation. |
| * |
| * A size of 0 disables external pause control. The maximum size is 1024. |
| */ |
| static void fsl_chan_set_request_count(struct fsldma_chan *chan, int size) |
| { |
| u32 mode; |
| |
| BUG_ON(size > 1024); |
| |
| mode = DMA_IN(chan, &chan->regs->mr, 32); |
| mode |= (__ilog2(size) << 24) & 0x0f000000; |
| |
| DMA_OUT(chan, &chan->regs->mr, mode, 32); |
| } |
| |
| /** |
| * fsl_chan_toggle_ext_pause - Toggle channel external pause status |
| * @chan : Freescale DMA channel |
| * @enable : 0 is disabled, 1 is enabled. |
| * |
| * The Freescale DMA channel can be controlled by the external signal DREQ#. |
| * The DMA Request Count feature should be used in addition to this feature |
| * to set the number of bytes to transfer before pausing the channel. |
| */ |
| static void fsl_chan_toggle_ext_pause(struct fsldma_chan *chan, int enable) |
| { |
| if (enable) |
| chan->feature |= FSL_DMA_CHAN_PAUSE_EXT; |
| else |
| chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT; |
| } |
| |
| /** |
| * fsl_chan_toggle_ext_start - Toggle channel external start status |
| * @chan : Freescale DMA channel |
| * @enable : 0 is disabled, 1 is enabled. |
| * |
| * If enable the external start, the channel can be started by an |
| * external DMA start pin. So the dma_start() does not start the |
| * transfer immediately. The DMA channel will wait for the |
| * control pin asserted. |
| */ |
| static void fsl_chan_toggle_ext_start(struct fsldma_chan *chan, int enable) |
| { |
| if (enable) |
| chan->feature |= FSL_DMA_CHAN_START_EXT; |
| else |
| chan->feature &= ~FSL_DMA_CHAN_START_EXT; |
| } |
| |
| static void append_ld_queue(struct fsldma_chan *chan, struct fsl_desc_sw *desc) |
| { |
| struct fsl_desc_sw *tail = to_fsl_desc(chan->ld_pending.prev); |
| |
| if (list_empty(&chan->ld_pending)) |
| goto out_splice; |
| |
| /* |
| * Add the hardware descriptor to the chain of hardware descriptors |
| * that already exists in memory. |
| * |
| * This will un-set the EOL bit of the existing transaction, and the |
| * last link in this transaction will become the EOL descriptor. |
| */ |
| set_desc_next(chan, &tail->hw, desc->async_tx.phys); |
| |
| /* |
| * Add the software descriptor and all children to the list |
| * of pending transactions |
| */ |
| out_splice: |
| list_splice_tail_init(&desc->tx_list, &chan->ld_pending); |
| } |
| |
| static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx) |
| { |
| struct fsldma_chan *chan = to_fsl_chan(tx->chan); |
| struct fsl_desc_sw *desc = tx_to_fsl_desc(tx); |
| struct fsl_desc_sw *child; |
| unsigned long flags; |
| dma_cookie_t cookie; |
| |
| spin_lock_irqsave(&chan->desc_lock, flags); |
| |
| /* |
| * assign cookies to all of the software descriptors |
| * that make up this transaction |
| */ |
| cookie = chan->common.cookie; |
| list_for_each_entry(child, &desc->tx_list, node) { |
| cookie++; |
| if (cookie < DMA_MIN_COOKIE) |
| cookie = DMA_MIN_COOKIE; |
| |
| child->async_tx.cookie = cookie; |
| } |
| |
| chan->common.cookie = cookie; |
| |
| /* put this transaction onto the tail of the pending queue */ |
| append_ld_queue(chan, desc); |
| |
| spin_unlock_irqrestore(&chan->desc_lock, flags); |
| |
| return cookie; |
| } |
| |
| /** |
| * fsl_dma_alloc_descriptor - Allocate descriptor from channel's DMA pool. |
| * @chan : Freescale DMA channel |
| * |
| * Return - The descriptor allocated. NULL for failed. |
| */ |
| static struct fsl_desc_sw *fsl_dma_alloc_descriptor(struct fsldma_chan *chan) |
| { |
| struct fsl_desc_sw *desc; |
| dma_addr_t pdesc; |
| |
| desc = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &pdesc); |
| if (!desc) { |
| chan_dbg(chan, "out of memory for link descriptor\n"); |
| return NULL; |
| } |
| |
| memset(desc, 0, sizeof(*desc)); |
| INIT_LIST_HEAD(&desc->tx_list); |
| dma_async_tx_descriptor_init(&desc->async_tx, &chan->common); |
| desc->async_tx.tx_submit = fsl_dma_tx_submit; |
| desc->async_tx.phys = pdesc; |
| |
| #ifdef FSL_DMA_LD_DEBUG |
| chan_dbg(chan, "LD %p allocated\n", desc); |
| #endif |
| |
| return desc; |
| } |
| |
| /** |
| * fsl_dma_alloc_chan_resources - Allocate resources for DMA channel. |
| * @chan : Freescale DMA channel |
| * |
| * This function will create a dma pool for descriptor allocation. |
| * |
| * Return - The number of descriptors allocated. |
| */ |
| static int fsl_dma_alloc_chan_resources(struct dma_chan *dchan) |
| { |
| struct fsldma_chan *chan = to_fsl_chan(dchan); |
| |
| /* Has this channel already been allocated? */ |
| if (chan->desc_pool) |
| return 1; |
| |
| /* |
| * We need the descriptor to be aligned to 32bytes |
| * for meeting FSL DMA specification requirement. |
| */ |
| chan->desc_pool = dma_pool_create(chan->name, chan->dev, |
| sizeof(struct fsl_desc_sw), |
| __alignof__(struct fsl_desc_sw), 0); |
| if (!chan->desc_pool) { |
| chan_err(chan, "unable to allocate descriptor pool\n"); |
| return -ENOMEM; |
| } |
| |
| /* there is at least one descriptor free to be allocated */ |
| return 1; |
| } |
| |
| /** |
| * fsldma_free_desc_list - Free all descriptors in a queue |
| * @chan: Freescae DMA channel |
| * @list: the list to free |
| * |
| * LOCKING: must hold chan->desc_lock |
| */ |
| static void fsldma_free_desc_list(struct fsldma_chan *chan, |
| struct list_head *list) |
| { |
| struct fsl_desc_sw *desc, *_desc; |
| |
| list_for_each_entry_safe(desc, _desc, list, node) { |
| list_del(&desc->node); |
| #ifdef FSL_DMA_LD_DEBUG |
| chan_dbg(chan, "LD %p free\n", desc); |
| #endif |
| dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys); |
| } |
| } |
| |
| static void fsldma_free_desc_list_reverse(struct fsldma_chan *chan, |
| struct list_head *list) |
| { |
| struct fsl_desc_sw *desc, *_desc; |
| |
| list_for_each_entry_safe_reverse(desc, _desc, list, node) { |
| list_del(&desc->node); |
| #ifdef FSL_DMA_LD_DEBUG |
| chan_dbg(chan, "LD %p free\n", desc); |
| #endif |
| dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys); |
| } |
| } |
| |
| /** |
| * fsl_dma_free_chan_resources - Free all resources of the channel. |
| * @chan : Freescale DMA channel |
| */ |
| static void fsl_dma_free_chan_resources(struct dma_chan *dchan) |
| { |
| struct fsldma_chan *chan = to_fsl_chan(dchan); |
| unsigned long flags; |
| |
| chan_dbg(chan, "free all channel resources\n"); |
| spin_lock_irqsave(&chan->desc_lock, flags); |
| fsldma_free_desc_list(chan, &chan->ld_pending); |
| fsldma_free_desc_list(chan, &chan->ld_running); |
| spin_unlock_irqrestore(&chan->desc_lock, flags); |
| |
| dma_pool_destroy(chan->desc_pool); |
| chan->desc_pool = NULL; |
| } |
| |
| static struct dma_async_tx_descriptor * |
| fsl_dma_prep_interrupt(struct dma_chan *dchan, unsigned long flags) |
| { |
| struct fsldma_chan *chan; |
| struct fsl_desc_sw *new; |
| |
| if (!dchan) |
| return NULL; |
| |
| chan = to_fsl_chan(dchan); |
| |
| new = fsl_dma_alloc_descriptor(chan); |
| if (!new) { |
| chan_err(chan, "%s\n", msg_ld_oom); |
| return NULL; |
| } |
| |
| new->async_tx.cookie = -EBUSY; |
| new->async_tx.flags = flags; |
| |
| /* Insert the link descriptor to the LD ring */ |
| list_add_tail(&new->node, &new->tx_list); |
| |
| /* Set End-of-link to the last link descriptor of new list */ |
| set_ld_eol(chan, new); |
| |
| return &new->async_tx; |
| } |
| |
| static struct dma_async_tx_descriptor * |
| fsl_dma_prep_memcpy(struct dma_chan *dchan, |
| dma_addr_t dma_dst, dma_addr_t dma_src, |
| size_t len, unsigned long flags) |
| { |
| struct fsldma_chan *chan; |
| struct fsl_desc_sw *first = NULL, *prev = NULL, *new; |
| size_t copy; |
| |
| if (!dchan) |
| return NULL; |
| |
| if (!len) |
| return NULL; |
| |
| chan = to_fsl_chan(dchan); |
| |
| do { |
| |
| /* Allocate the link descriptor from DMA pool */ |
| new = fsl_dma_alloc_descriptor(chan); |
| if (!new) { |
| chan_err(chan, "%s\n", msg_ld_oom); |
| goto fail; |
| } |
| |
| copy = min(len, (size_t)FSL_DMA_BCR_MAX_CNT); |
| |
| set_desc_cnt(chan, &new->hw, copy); |
| set_desc_src(chan, &new->hw, dma_src); |
| set_desc_dst(chan, &new->hw, dma_dst); |
| |
| if (!first) |
| first = new; |
| else |
| set_desc_next(chan, &prev->hw, new->async_tx.phys); |
| |
| new->async_tx.cookie = 0; |
| async_tx_ack(&new->async_tx); |
| |
| prev = new; |
| len -= copy; |
| dma_src += copy; |
| dma_dst += copy; |
| |
| /* Insert the link descriptor to the LD ring */ |
| list_add_tail(&new->node, &first->tx_list); |
| } while (len); |
| |
| new->async_tx.flags = flags; /* client is in control of this ack */ |
| new->async_tx.cookie = -EBUSY; |
| |
| /* Set End-of-link to the last link descriptor of new list */ |
| set_ld_eol(chan, new); |
| |
| return &first->async_tx; |
| |
| fail: |
| if (!first) |
| return NULL; |
| |
| fsldma_free_desc_list_reverse(chan, &first->tx_list); |
| return NULL; |
| } |
| |
| static struct dma_async_tx_descriptor *fsl_dma_prep_sg(struct dma_chan *dchan, |
| struct scatterlist *dst_sg, unsigned int dst_nents, |
| struct scatterlist *src_sg, unsigned int src_nents, |
| unsigned long flags) |
| { |
| struct fsl_desc_sw *first = NULL, *prev = NULL, *new = NULL; |
| struct fsldma_chan *chan = to_fsl_chan(dchan); |
| size_t dst_avail, src_avail; |
| dma_addr_t dst, src; |
| size_t len; |
| |
| /* basic sanity checks */ |
| if (dst_nents == 0 || src_nents == 0) |
| return NULL; |
| |
| if (dst_sg == NULL || src_sg == NULL) |
| return NULL; |
| |
| /* |
| * TODO: should we check that both scatterlists have the same |
| * TODO: number of bytes in total? Is that really an error? |
| */ |
| |
| /* get prepared for the loop */ |
| dst_avail = sg_dma_len(dst_sg); |
| src_avail = sg_dma_len(src_sg); |
| |
| /* run until we are out of scatterlist entries */ |
| while (true) { |
| |
| /* create the largest transaction possible */ |
| len = min_t(size_t, src_avail, dst_avail); |
| len = min_t(size_t, len, FSL_DMA_BCR_MAX_CNT); |
| if (len == 0) |
| goto fetch; |
| |
| dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) - dst_avail; |
| src = sg_dma_address(src_sg) + sg_dma_len(src_sg) - src_avail; |
| |
| /* allocate and populate the descriptor */ |
| new = fsl_dma_alloc_descriptor(chan); |
| if (!new) { |
| chan_err(chan, "%s\n", msg_ld_oom); |
| goto fail; |
| } |
| |
| set_desc_cnt(chan, &new->hw, len); |
| set_desc_src(chan, &new->hw, src); |
| set_desc_dst(chan, &new->hw, dst); |
| |
| if (!first) |
| first = new; |
| else |
| set_desc_next(chan, &prev->hw, new->async_tx.phys); |
| |
| new->async_tx.cookie = 0; |
| async_tx_ack(&new->async_tx); |
| prev = new; |
| |
| /* Insert the link descriptor to the LD ring */ |
| list_add_tail(&new->node, &first->tx_list); |
| |
| /* update metadata */ |
| dst_avail -= len; |
| src_avail -= len; |
| |
| fetch: |
| /* fetch the next dst scatterlist entry */ |
| if (dst_avail == 0) { |
| |
| /* no more entries: we're done */ |
| if (dst_nents == 0) |
| break; |
| |
| /* fetch the next entry: if there are no more: done */ |
| dst_sg = sg_next(dst_sg); |
| if (dst_sg == NULL) |
| break; |
| |
| dst_nents--; |
| dst_avail = sg_dma_len(dst_sg); |
| } |
| |
| /* fetch the next src scatterlist entry */ |
| if (src_avail == 0) { |
| |
| /* no more entries: we're done */ |
| if (src_nents == 0) |
| break; |
| |
| /* fetch the next entry: if there are no more: done */ |
| src_sg = sg_next(src_sg); |
| if (src_sg == NULL) |
| break; |
| |
| src_nents--; |
| src_avail = sg_dma_len(src_sg); |
| } |
| } |
| |
| new->async_tx.flags = flags; /* client is in control of this ack */ |
| new->async_tx.cookie = -EBUSY; |
| |
| /* Set End-of-link to the last link descriptor of new list */ |
| set_ld_eol(chan, new); |
| |
| return &first->async_tx; |
| |
| fail: |
| if (!first) |
| return NULL; |
| |
| fsldma_free_desc_list_reverse(chan, &first->tx_list); |
| return NULL; |
| } |
| |
| /** |
| * fsl_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction |
| * @chan: DMA channel |
| * @sgl: scatterlist to transfer to/from |
| * @sg_len: number of entries in @scatterlist |
| * @direction: DMA direction |
| * @flags: DMAEngine flags |
| * |
| * Prepare a set of descriptors for a DMA_SLAVE transaction. Following the |
| * DMA_SLAVE API, this gets the device-specific information from the |
| * chan->private variable. |
| */ |
| static struct dma_async_tx_descriptor *fsl_dma_prep_slave_sg( |
| struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len, |
| enum dma_transfer_direction direction, unsigned long flags) |
| { |
| /* |
| * This operation is not supported on the Freescale DMA controller |
| * |
| * However, we need to provide the function pointer to allow the |
| * device_control() method to work. |
| */ |
| return NULL; |
| } |
| |
| static int fsl_dma_device_control(struct dma_chan *dchan, |
| enum dma_ctrl_cmd cmd, unsigned long arg) |
| { |
| struct dma_slave_config *config; |
| struct fsldma_chan *chan; |
| unsigned long flags; |
| int size; |
| |
| if (!dchan) |
| return -EINVAL; |
| |
| chan = to_fsl_chan(dchan); |
| |
| switch (cmd) { |
| case DMA_TERMINATE_ALL: |
| spin_lock_irqsave(&chan->desc_lock, flags); |
| |
| /* Halt the DMA engine */ |
| dma_halt(chan); |
| |
| /* Remove and free all of the descriptors in the LD queue */ |
| fsldma_free_desc_list(chan, &chan->ld_pending); |
| fsldma_free_desc_list(chan, &chan->ld_running); |
| chan->idle = true; |
| |
| spin_unlock_irqrestore(&chan->desc_lock, flags); |
| return 0; |
| |
| case DMA_SLAVE_CONFIG: |
| config = (struct dma_slave_config *)arg; |
| |
| /* make sure the channel supports setting burst size */ |
| if (!chan->set_request_count) |
| return -ENXIO; |
| |
| /* we set the controller burst size depending on direction */ |
| if (config->direction == DMA_MEM_TO_DEV) |
| size = config->dst_addr_width * config->dst_maxburst; |
| else |
| size = config->src_addr_width * config->src_maxburst; |
| |
| chan->set_request_count(chan, size); |
| return 0; |
| |
| case FSLDMA_EXTERNAL_START: |
| |
| /* make sure the channel supports external start */ |
| if (!chan->toggle_ext_start) |
| return -ENXIO; |
| |
| chan->toggle_ext_start(chan, arg); |
| return 0; |
| |
| default: |
| return -ENXIO; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * fsldma_cleanup_descriptor - cleanup and free a single link descriptor |
| * @chan: Freescale DMA channel |
| * @desc: descriptor to cleanup and free |
| * |
| * This function is used on a descriptor which has been executed by the DMA |
| * controller. It will run any callbacks, submit any dependencies, and then |
| * free the descriptor. |
| */ |
| static void fsldma_cleanup_descriptor(struct fsldma_chan *chan, |
| struct fsl_desc_sw *desc) |
| { |
| struct dma_async_tx_descriptor *txd = &desc->async_tx; |
| struct device *dev = chan->common.device->dev; |
| dma_addr_t src = get_desc_src(chan, desc); |
| dma_addr_t dst = get_desc_dst(chan, desc); |
| u32 len = get_desc_cnt(chan, desc); |
| |
| /* Run the link descriptor callback function */ |
| if (txd->callback) { |
| #ifdef FSL_DMA_LD_DEBUG |
| chan_dbg(chan, "LD %p callback\n", desc); |
| #endif |
| txd->callback(txd->callback_param); |
| } |
| |
| /* Run any dependencies */ |
| dma_run_dependencies(txd); |
| |
| /* Unmap the dst buffer, if requested */ |
| if (!(txd->flags & DMA_COMPL_SKIP_DEST_UNMAP)) { |
| if (txd->flags & DMA_COMPL_DEST_UNMAP_SINGLE) |
| dma_unmap_single(dev, dst, len, DMA_FROM_DEVICE); |
| else |
| dma_unmap_page(dev, dst, len, DMA_FROM_DEVICE); |
| } |
| |
| /* Unmap the src buffer, if requested */ |
| if (!(txd->flags & DMA_COMPL_SKIP_SRC_UNMAP)) { |
| if (txd->flags & DMA_COMPL_SRC_UNMAP_SINGLE) |
| dma_unmap_single(dev, src, len, DMA_TO_DEVICE); |
| else |
| dma_unmap_page(dev, src, len, DMA_TO_DEVICE); |
| } |
| |
| #ifdef FSL_DMA_LD_DEBUG |
| chan_dbg(chan, "LD %p free\n", desc); |
| #endif |
| dma_pool_free(chan->desc_pool, desc, txd->phys); |
| } |
| |
| /** |
| * fsl_chan_xfer_ld_queue - transfer any pending transactions |
| * @chan : Freescale DMA channel |
| * |
| * HARDWARE STATE: idle |
| * LOCKING: must hold chan->desc_lock |
| */ |
| static void fsl_chan_xfer_ld_queue(struct fsldma_chan *chan) |
| { |
| struct fsl_desc_sw *desc; |
| |
| /* |
| * If the list of pending descriptors is empty, then we |
| * don't need to do any work at all |
| */ |
| if (list_empty(&chan->ld_pending)) { |
| chan_dbg(chan, "no pending LDs\n"); |
| return; |
| } |
| |
| /* |
| * The DMA controller is not idle, which means that the interrupt |
| * handler will start any queued transactions when it runs after |
| * this transaction finishes |
| */ |
| if (!chan->idle) { |
| chan_dbg(chan, "DMA controller still busy\n"); |
| return; |
| } |
| |
| /* |
| * If there are some link descriptors which have not been |
| * transferred, we need to start the controller |
| */ |
| |
| /* |
| * Move all elements from the queue of pending transactions |
| * onto the list of running transactions |
| */ |
| chan_dbg(chan, "idle, starting controller\n"); |
| desc = list_first_entry(&chan->ld_pending, struct fsl_desc_sw, node); |
| list_splice_tail_init(&chan->ld_pending, &chan->ld_running); |
| |
| /* |
| * The 85xx DMA controller doesn't clear the channel start bit |
| * automatically at the end of a transfer. Therefore we must clear |
| * it in software before starting the transfer. |
| */ |
| if ((chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX) { |
| u32 mode; |
| |
| mode = DMA_IN(chan, &chan->regs->mr, 32); |
| mode &= ~FSL_DMA_MR_CS; |
| DMA_OUT(chan, &chan->regs->mr, mode, 32); |
| } |
| |
| /* |
| * Program the descriptor's address into the DMA controller, |
| * then start the DMA transaction |
| */ |
| set_cdar(chan, desc->async_tx.phys); |
| get_cdar(chan); |
| |
| dma_start(chan); |
| chan->idle = false; |
| } |
| |
| /** |
| * fsl_dma_memcpy_issue_pending - Issue the DMA start command |
| * @chan : Freescale DMA channel |
| */ |
| static void fsl_dma_memcpy_issue_pending(struct dma_chan *dchan) |
| { |
| struct fsldma_chan *chan = to_fsl_chan(dchan); |
| unsigned long flags; |
| |
| spin_lock_irqsave(&chan->desc_lock, flags); |
| fsl_chan_xfer_ld_queue(chan); |
| spin_unlock_irqrestore(&chan->desc_lock, flags); |
| } |
| |
| /** |
| * fsl_tx_status - Determine the DMA status |
| * @chan : Freescale DMA channel |
| */ |
| static enum dma_status fsl_tx_status(struct dma_chan *dchan, |
| dma_cookie_t cookie, |
| struct dma_tx_state *txstate) |
| { |
| struct fsldma_chan *chan = to_fsl_chan(dchan); |
| dma_cookie_t last_complete; |
| dma_cookie_t last_used; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&chan->desc_lock, flags); |
| |
| last_complete = dchan->completed_cookie; |
| last_used = dchan->cookie; |
| |
| spin_unlock_irqrestore(&chan->desc_lock, flags); |
| |
| dma_set_tx_state(txstate, last_complete, last_used, 0); |
| return dma_async_is_complete(cookie, last_complete, last_used); |
| } |
| |
| /*----------------------------------------------------------------------------*/ |
| /* Interrupt Handling */ |
| /*----------------------------------------------------------------------------*/ |
| |
| static irqreturn_t fsldma_chan_irq(int irq, void *data) |
| { |
| struct fsldma_chan *chan = data; |
| u32 stat; |
| |
| /* save and clear the status register */ |
| stat = get_sr(chan); |
| set_sr(chan, stat); |
| chan_dbg(chan, "irq: stat = 0x%x\n", stat); |
| |
| /* check that this was really our device */ |
| stat &= ~(FSL_DMA_SR_CB | FSL_DMA_SR_CH); |
| if (!stat) |
| return IRQ_NONE; |
| |
| if (stat & FSL_DMA_SR_TE) |
| chan_err(chan, "Transfer Error!\n"); |
| |
| /* |
| * Programming Error |
| * The DMA_INTERRUPT async_tx is a NULL transfer, which will |
| * triger a PE interrupt. |
| */ |
| if (stat & FSL_DMA_SR_PE) { |
| chan_dbg(chan, "irq: Programming Error INT\n"); |
| stat &= ~FSL_DMA_SR_PE; |
| if (get_bcr(chan) != 0) |
| chan_err(chan, "Programming Error!\n"); |
| } |
| |
| /* |
| * For MPC8349, EOCDI event need to update cookie |
| * and start the next transfer if it exist. |
| */ |
| if (stat & FSL_DMA_SR_EOCDI) { |
| chan_dbg(chan, "irq: End-of-Chain link INT\n"); |
| stat &= ~FSL_DMA_SR_EOCDI; |
| } |
| |
| /* |
| * If it current transfer is the end-of-transfer, |
| * we should clear the Channel Start bit for |
| * prepare next transfer. |
| */ |
| if (stat & FSL_DMA_SR_EOLNI) { |
| chan_dbg(chan, "irq: End-of-link INT\n"); |
| stat &= ~FSL_DMA_SR_EOLNI; |
| } |
| |
| /* check that the DMA controller is really idle */ |
| if (!dma_is_idle(chan)) |
| chan_err(chan, "irq: controller not idle!\n"); |
| |
| /* check that we handled all of the bits */ |
| if (stat) |
| chan_err(chan, "irq: unhandled sr 0x%08x\n", stat); |
| |
| /* |
| * Schedule the tasklet to handle all cleanup of the current |
| * transaction. It will start a new transaction if there is |
| * one pending. |
| */ |
| tasklet_schedule(&chan->tasklet); |
| chan_dbg(chan, "irq: Exit\n"); |
| return IRQ_HANDLED; |
| } |
| |
| static void dma_do_tasklet(unsigned long data) |
| { |
| struct fsldma_chan *chan = (struct fsldma_chan *)data; |
| struct fsl_desc_sw *desc, *_desc; |
| LIST_HEAD(ld_cleanup); |
| unsigned long flags; |
| |
| chan_dbg(chan, "tasklet entry\n"); |
| |
| spin_lock_irqsave(&chan->desc_lock, flags); |
| |
| /* update the cookie if we have some descriptors to cleanup */ |
| if (!list_empty(&chan->ld_running)) { |
| dma_cookie_t cookie; |
| |
| desc = to_fsl_desc(chan->ld_running.prev); |
| cookie = desc->async_tx.cookie; |
| |
| chan->common.completed_cookie = cookie; |
| chan_dbg(chan, "completed_cookie=%d\n", cookie); |
| } |
| |
| /* |
| * move the descriptors to a temporary list so we can drop the lock |
| * during the entire cleanup operation |
| */ |
| list_splice_tail_init(&chan->ld_running, &ld_cleanup); |
| |
| /* the hardware is now idle and ready for more */ |
| chan->idle = true; |
| |
| /* |
| * Start any pending transactions automatically |
| * |
| * In the ideal case, we keep the DMA controller busy while we go |
| * ahead and free the descriptors below. |
| */ |
| fsl_chan_xfer_ld_queue(chan); |
| spin_unlock_irqrestore(&chan->desc_lock, flags); |
| |
| /* Run the callback for each descriptor, in order */ |
| list_for_each_entry_safe(desc, _desc, &ld_cleanup, node) { |
| |
| /* Remove from the list of transactions */ |
| list_del(&desc->node); |
| |
| /* Run all cleanup for this descriptor */ |
| fsldma_cleanup_descriptor(chan, desc); |
| } |
| |
| chan_dbg(chan, "tasklet exit\n"); |
| } |
| |
| static irqreturn_t fsldma_ctrl_irq(int irq, void *data) |
| { |
| struct fsldma_device *fdev = data; |
| struct fsldma_chan *chan; |
| unsigned int handled = 0; |
| u32 gsr, mask; |
| int i; |
| |
| gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->regs) |
| : in_le32(fdev->regs); |
| mask = 0xff000000; |
| dev_dbg(fdev->dev, "IRQ: gsr 0x%.8x\n", gsr); |
| |
| for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { |
| chan = fdev->chan[i]; |
| if (!chan) |
| continue; |
| |
| if (gsr & mask) { |
| dev_dbg(fdev->dev, "IRQ: chan %d\n", chan->id); |
| fsldma_chan_irq(irq, chan); |
| handled++; |
| } |
| |
| gsr &= ~mask; |
| mask >>= 8; |
| } |
| |
| return IRQ_RETVAL(handled); |
| } |
| |
| static void fsldma_free_irqs(struct fsldma_device *fdev) |
| { |
| struct fsldma_chan *chan; |
| int i; |
| |
| if (fdev->irq != NO_IRQ) { |
| dev_dbg(fdev->dev, "free per-controller IRQ\n"); |
| free_irq(fdev->irq, fdev); |
| return; |
| } |
| |
| for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { |
| chan = fdev->chan[i]; |
| if (chan && chan->irq != NO_IRQ) { |
| chan_dbg(chan, "free per-channel IRQ\n"); |
| free_irq(chan->irq, chan); |
| } |
| } |
| } |
| |
| static int fsldma_request_irqs(struct fsldma_device *fdev) |
| { |
| struct fsldma_chan *chan; |
| int ret; |
| int i; |
| |
| /* if we have a per-controller IRQ, use that */ |
| if (fdev->irq != NO_IRQ) { |
| dev_dbg(fdev->dev, "request per-controller IRQ\n"); |
| ret = request_irq(fdev->irq, fsldma_ctrl_irq, IRQF_SHARED, |
| "fsldma-controller", fdev); |
| return ret; |
| } |
| |
| /* no per-controller IRQ, use the per-channel IRQs */ |
| for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { |
| chan = fdev->chan[i]; |
| if (!chan) |
| continue; |
| |
| if (chan->irq == NO_IRQ) { |
| chan_err(chan, "interrupts property missing in device tree\n"); |
| ret = -ENODEV; |
| goto out_unwind; |
| } |
| |
| chan_dbg(chan, "request per-channel IRQ\n"); |
| ret = request_irq(chan->irq, fsldma_chan_irq, IRQF_SHARED, |
| "fsldma-chan", chan); |
| if (ret) { |
| chan_err(chan, "unable to request per-channel IRQ\n"); |
| goto out_unwind; |
| } |
| } |
| |
| return 0; |
| |
| out_unwind: |
| for (/* none */; i >= 0; i--) { |
| chan = fdev->chan[i]; |
| if (!chan) |
| continue; |
| |
| if (chan->irq == NO_IRQ) |
| continue; |
| |
| free_irq(chan->irq, chan); |
| } |
| |
| return ret; |
| } |
| |
| /*----------------------------------------------------------------------------*/ |
| /* OpenFirmware Subsystem */ |
| /*----------------------------------------------------------------------------*/ |
| |
| static int __devinit fsl_dma_chan_probe(struct fsldma_device *fdev, |
| struct device_node *node, u32 feature, const char *compatible) |
| { |
| struct fsldma_chan *chan; |
| struct resource res; |
| int err; |
| |
| /* alloc channel */ |
| chan = kzalloc(sizeof(*chan), GFP_KERNEL); |
| if (!chan) { |
| dev_err(fdev->dev, "no free memory for DMA channels!\n"); |
| err = -ENOMEM; |
| goto out_return; |
| } |
| |
| /* ioremap registers for use */ |
| chan->regs = of_iomap(node, 0); |
| if (!chan->regs) { |
| dev_err(fdev->dev, "unable to ioremap registers\n"); |
| err = -ENOMEM; |
| goto out_free_chan; |
| } |
| |
| err = of_address_to_resource(node, 0, &res); |
| if (err) { |
| dev_err(fdev->dev, "unable to find 'reg' property\n"); |
| goto out_iounmap_regs; |
| } |
| |
| chan->feature = feature; |
| if (!fdev->feature) |
| fdev->feature = chan->feature; |
| |
| /* |
| * If the DMA device's feature is different than the feature |
| * of its channels, report the bug |
| */ |
| WARN_ON(fdev->feature != chan->feature); |
| |
| chan->dev = fdev->dev; |
| chan->id = ((res.start - 0x100) & 0xfff) >> 7; |
| if (chan->id >= FSL_DMA_MAX_CHANS_PER_DEVICE) { |
| dev_err(fdev->dev, "too many channels for device\n"); |
| err = -EINVAL; |
| goto out_iounmap_regs; |
| } |
| |
| fdev->chan[chan->id] = chan; |
| tasklet_init(&chan->tasklet, dma_do_tasklet, (unsigned long)chan); |
| snprintf(chan->name, sizeof(chan->name), "chan%d", chan->id); |
| |
| /* Initialize the channel */ |
| dma_init(chan); |
| |
| /* Clear cdar registers */ |
| set_cdar(chan, 0); |
| |
| switch (chan->feature & FSL_DMA_IP_MASK) { |
| case FSL_DMA_IP_85XX: |
| chan->toggle_ext_pause = fsl_chan_toggle_ext_pause; |
| case FSL_DMA_IP_83XX: |
| chan->toggle_ext_start = fsl_chan_toggle_ext_start; |
| chan->set_src_loop_size = fsl_chan_set_src_loop_size; |
| chan->set_dst_loop_size = fsl_chan_set_dst_loop_size; |
| chan->set_request_count = fsl_chan_set_request_count; |
| } |
| |
| spin_lock_init(&chan->desc_lock); |
| INIT_LIST_HEAD(&chan->ld_pending); |
| INIT_LIST_HEAD(&chan->ld_running); |
| chan->idle = true; |
| |
| chan->common.device = &fdev->common; |
| |
| /* find the IRQ line, if it exists in the device tree */ |
| chan->irq = irq_of_parse_and_map(node, 0); |
| |
| /* Add the channel to DMA device channel list */ |
| list_add_tail(&chan->common.device_node, &fdev->common.channels); |
| fdev->common.chancnt++; |
| |
| dev_info(fdev->dev, "#%d (%s), irq %d\n", chan->id, compatible, |
| chan->irq != NO_IRQ ? chan->irq : fdev->irq); |
| |
| return 0; |
| |
| out_iounmap_regs: |
| iounmap(chan->regs); |
| out_free_chan: |
| kfree(chan); |
| out_return: |
| return err; |
| } |
| |
| static void fsl_dma_chan_remove(struct fsldma_chan *chan) |
| { |
| irq_dispose_mapping(chan->irq); |
| list_del(&chan->common.device_node); |
| iounmap(chan->regs); |
| kfree(chan); |
| } |
| |
| static int __devinit fsldma_of_probe(struct platform_device *op) |
| { |
| struct fsldma_device *fdev; |
| struct device_node *child; |
| int err; |
| |
| fdev = kzalloc(sizeof(*fdev), GFP_KERNEL); |
| if (!fdev) { |
| dev_err(&op->dev, "No enough memory for 'priv'\n"); |
| err = -ENOMEM; |
| goto out_return; |
| } |
| |
| fdev->dev = &op->dev; |
| INIT_LIST_HEAD(&fdev->common.channels); |
| |
| /* ioremap the registers for use */ |
| fdev->regs = of_iomap(op->dev.of_node, 0); |
| if (!fdev->regs) { |
| dev_err(&op->dev, "unable to ioremap registers\n"); |
| err = -ENOMEM; |
| goto out_free_fdev; |
| } |
| |
| /* map the channel IRQ if it exists, but don't hookup the handler yet */ |
| fdev->irq = irq_of_parse_and_map(op->dev.of_node, 0); |
| |
| dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask); |
| dma_cap_set(DMA_INTERRUPT, fdev->common.cap_mask); |
| dma_cap_set(DMA_SG, fdev->common.cap_mask); |
| dma_cap_set(DMA_SLAVE, fdev->common.cap_mask); |
| fdev->common.device_alloc_chan_resources = fsl_dma_alloc_chan_resources; |
| fdev->common.device_free_chan_resources = fsl_dma_free_chan_resources; |
| fdev->common.device_prep_dma_interrupt = fsl_dma_prep_interrupt; |
| fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy; |
| fdev->common.device_prep_dma_sg = fsl_dma_prep_sg; |
| fdev->common.device_tx_status = fsl_tx_status; |
| fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending; |
| fdev->common.device_prep_slave_sg = fsl_dma_prep_slave_sg; |
| fdev->common.device_control = fsl_dma_device_control; |
| fdev->common.dev = &op->dev; |
| |
| dma_set_mask(&(op->dev), DMA_BIT_MASK(36)); |
| |
| dev_set_drvdata(&op->dev, fdev); |
| |
| /* |
| * We cannot use of_platform_bus_probe() because there is no |
| * of_platform_bus_remove(). Instead, we manually instantiate every DMA |
| * channel object. |
| */ |
| for_each_child_of_node(op->dev.of_node, child) { |
| if (of_device_is_compatible(child, "fsl,eloplus-dma-channel")) { |
| fsl_dma_chan_probe(fdev, child, |
| FSL_DMA_IP_85XX | FSL_DMA_BIG_ENDIAN, |
| "fsl,eloplus-dma-channel"); |
| } |
| |
| if (of_device_is_compatible(child, "fsl,elo-dma-channel")) { |
| fsl_dma_chan_probe(fdev, child, |
| FSL_DMA_IP_83XX | FSL_DMA_LITTLE_ENDIAN, |
| "fsl,elo-dma-channel"); |
| } |
| } |
| |
| /* |
| * Hookup the IRQ handler(s) |
| * |
| * If we have a per-controller interrupt, we prefer that to the |
| * per-channel interrupts to reduce the number of shared interrupt |
| * handlers on the same IRQ line |
| */ |
| err = fsldma_request_irqs(fdev); |
| if (err) { |
| dev_err(fdev->dev, "unable to request IRQs\n"); |
| goto out_free_fdev; |
| } |
| |
| dma_async_device_register(&fdev->common); |
| return 0; |
| |
| out_free_fdev: |
| irq_dispose_mapping(fdev->irq); |
| kfree(fdev); |
| out_return: |
| return err; |
| } |
| |
| static int fsldma_of_remove(struct platform_device *op) |
| { |
| struct fsldma_device *fdev; |
| unsigned int i; |
| |
| fdev = dev_get_drvdata(&op->dev); |
| dma_async_device_unregister(&fdev->common); |
| |
| fsldma_free_irqs(fdev); |
| |
| for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { |
| if (fdev->chan[i]) |
| fsl_dma_chan_remove(fdev->chan[i]); |
| } |
| |
| iounmap(fdev->regs); |
| dev_set_drvdata(&op->dev, NULL); |
| kfree(fdev); |
| |
| return 0; |
| } |
| |
| static const struct of_device_id fsldma_of_ids[] = { |
| { .compatible = "fsl,eloplus-dma", }, |
| { .compatible = "fsl,elo-dma", }, |
| {} |
| }; |
| |
| static struct platform_driver fsldma_of_driver = { |
| .driver = { |
| .name = "fsl-elo-dma", |
| .owner = THIS_MODULE, |
| .of_match_table = fsldma_of_ids, |
| }, |
| .probe = fsldma_of_probe, |
| .remove = fsldma_of_remove, |
| }; |
| |
| /*----------------------------------------------------------------------------*/ |
| /* Module Init / Exit */ |
| /*----------------------------------------------------------------------------*/ |
| |
| static __init int fsldma_init(void) |
| { |
| pr_info("Freescale Elo / Elo Plus DMA driver\n"); |
| return platform_driver_register(&fsldma_of_driver); |
| } |
| |
| static void __exit fsldma_exit(void) |
| { |
| platform_driver_unregister(&fsldma_of_driver); |
| } |
| |
| subsys_initcall(fsldma_init); |
| module_exit(fsldma_exit); |
| |
| MODULE_DESCRIPTION("Freescale Elo / Elo Plus DMA driver"); |
| MODULE_LICENSE("GPL"); |