summaryrefslogtreecommitdiffstats
path: root/drivers/dma/fsldma.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/dma/fsldma.c')
-rw-r--r--drivers/dma/fsldma.c1036
1 files changed, 1036 insertions, 0 deletions
diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
new file mode 100644
index 0000000..0b95dcc
--- /dev/null
+++ b/drivers/dma/fsldma.c
@@ -0,0 +1,1036 @@
+/*
+ * Freescale MPC85xx, MPC83xx DMA Engine support
+ *
+ * Copyright (C) 2007 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 contorller is also added.
+ *
+ * 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/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 "fsldma.h"
+
+static void dma_init(struct fsl_dma_chan *fsl_chan)
+{
+ /* Reset the channel */
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, 0, 32);
+
+ switch (fsl_chan->feature & FSL_DMA_IP_MASK) {
+ case FSL_DMA_IP_85XX:
+ /* Set the channel to below modes:
+ * EIE - Error interrupt enable
+ * EOSIE - End of segments interrupt enable (basic mode)
+ * EOLNIE - End of links interrupt enable
+ */
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EIE
+ | FSL_DMA_MR_EOLNIE | FSL_DMA_MR_EOSIE, 32);
+ break;
+ case FSL_DMA_IP_83XX:
+ /* Set the channel to below modes:
+ * EOTIE - End-of-transfer interrupt enable
+ */
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EOTIE,
+ 32);
+ break;
+ }
+
+}
+
+static void set_sr(struct fsl_dma_chan *fsl_chan, u32 val)
+{
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->sr, val, 32);
+}
+
+static u32 get_sr(struct fsl_dma_chan *fsl_chan)
+{
+ return DMA_IN(fsl_chan, &fsl_chan->reg_base->sr, 32);
+}
+
+static void set_desc_cnt(struct fsl_dma_chan *fsl_chan,
+ struct fsl_dma_ld_hw *hw, u32 count)
+{
+ hw->count = CPU_TO_DMA(fsl_chan, count, 32);
+}
+
+static void set_desc_src(struct fsl_dma_chan *fsl_chan,
+ struct fsl_dma_ld_hw *hw, dma_addr_t src)
+{
+ u64 snoop_bits;
+
+ snoop_bits = ((fsl_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(fsl_chan, snoop_bits | src, 64);
+}
+
+static void set_desc_dest(struct fsl_dma_chan *fsl_chan,
+ struct fsl_dma_ld_hw *hw, dma_addr_t dest)
+{
+ u64 snoop_bits;
+
+ snoop_bits = ((fsl_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(fsl_chan, snoop_bits | dest, 64);
+}
+
+static void set_desc_next(struct fsl_dma_chan *fsl_chan,
+ struct fsl_dma_ld_hw *hw, dma_addr_t next)
+{
+ u64 snoop_bits;
+
+ snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX)
+ ? FSL_DMA_SNEN : 0;
+ hw->next_ln_addr = CPU_TO_DMA(fsl_chan, snoop_bits | next, 64);
+}
+
+static void set_cdar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
+{
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->cdar, addr | FSL_DMA_SNEN, 64);
+}
+
+static dma_addr_t get_cdar(struct fsl_dma_chan *fsl_chan)
+{
+ return DMA_IN(fsl_chan, &fsl_chan->reg_base->cdar, 64) & ~FSL_DMA_SNEN;
+}
+
+static void set_ndar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
+{
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->ndar, addr, 64);
+}
+
+static dma_addr_t get_ndar(struct fsl_dma_chan *fsl_chan)
+{
+ return DMA_IN(fsl_chan, &fsl_chan->reg_base->ndar, 64);
+}
+
+static u32 get_bcr(struct fsl_dma_chan *fsl_chan)
+{
+ return DMA_IN(fsl_chan, &fsl_chan->reg_base->bcr, 32);
+}
+
+static int dma_is_idle(struct fsl_dma_chan *fsl_chan)
+{
+ u32 sr = get_sr(fsl_chan);
+ return (!(sr & FSL_DMA_SR_CB)) || (sr & FSL_DMA_SR_CH);
+}
+
+static void dma_start(struct fsl_dma_chan *fsl_chan)
+{
+ u32 mr_set = 0;;
+
+ if (fsl_chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->bcr, 0, 32);
+ mr_set |= FSL_DMA_MR_EMP_EN;
+ } else
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
+ & ~FSL_DMA_MR_EMP_EN, 32);
+
+ if (fsl_chan->feature & FSL_DMA_CHAN_START_EXT)
+ mr_set |= FSL_DMA_MR_EMS_EN;
+ else
+ mr_set |= FSL_DMA_MR_CS;
+
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
+ | mr_set, 32);
+}
+
+static void dma_halt(struct fsl_dma_chan *fsl_chan)
+{
+ int i = 0;
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) | FSL_DMA_MR_CA,
+ 32);
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) & ~(FSL_DMA_MR_CS
+ | FSL_DMA_MR_EMS_EN | FSL_DMA_MR_CA), 32);
+
+ while (!dma_is_idle(fsl_chan) && (i++ < 100))
+ udelay(10);
+ if (i >= 100 && !dma_is_idle(fsl_chan))
+ dev_err(fsl_chan->dev, "DMA halt timeout!\n");
+}
+
+static void set_ld_eol(struct fsl_dma_chan *fsl_chan,
+ struct fsl_desc_sw *desc)
+{
+ desc->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
+ DMA_TO_CPU(fsl_chan, desc->hw.next_ln_addr, 64) | FSL_DMA_EOL,
+ 64);
+}
+
+static void append_ld_queue(struct fsl_dma_chan *fsl_chan,
+ struct fsl_desc_sw *new_desc)
+{
+ struct fsl_desc_sw *queue_tail = to_fsl_desc(fsl_chan->ld_queue.prev);
+
+ if (list_empty(&fsl_chan->ld_queue))
+ return;
+
+ /* Link to the new descriptor physical address and
+ * Enable End-of-segment interrupt for
+ * the last link descriptor.
+ * (the previous node's next link descriptor)
+ *
+ * For FSL_DMA_IP_83xx, the snoop enable bit need be set.
+ */
+ queue_tail->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
+ new_desc->async_tx.phys | FSL_DMA_EOSIE |
+ (((fsl_chan->feature & FSL_DMA_IP_MASK)
+ == FSL_DMA_IP_83XX) ? FSL_DMA_SNEN : 0), 64);
+}
+
+/**
+ * fsl_chan_set_src_loop_size - Set source address hold transfer size
+ * @fsl_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 fsl_dma_chan *fsl_chan, int size)
+{
+ switch (size) {
+ case 0:
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
+ (~FSL_DMA_MR_SAHE), 32);
+ break;
+ case 1:
+ case 2:
+ case 4:
+ case 8:
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
+ FSL_DMA_MR_SAHE | (__ilog2(size) << 14),
+ 32);
+ break;
+ }
+}
+
+/**
+ * fsl_chan_set_dest_loop_size - Set destination address hold transfer size
+ * @fsl_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_dest_loop_size(struct fsl_dma_chan *fsl_chan, int size)
+{
+ switch (size) {
+ case 0:
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
+ (~FSL_DMA_MR_DAHE), 32);
+ break;
+ case 1:
+ case 2:
+ case 4:
+ case 8:
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
+ FSL_DMA_MR_DAHE | (__ilog2(size) << 16),
+ 32);
+ break;
+ }
+}
+
+/**
+ * fsl_chan_toggle_ext_pause - Toggle channel external pause status
+ * @fsl_chan : Freescale DMA channel
+ * @size : Pause control size, 0 for disable external pause control.
+ * The maximum is 1024.
+ *
+ * The Freescale DMA channel can be controlled by the external
+ * signal DREQ#. The pause control size is how many bytes are allowed
+ * to transfer before pausing the channel, after which a new assertion
+ * of DREQ# resumes channel operation.
+ */
+static void fsl_chan_toggle_ext_pause(struct fsl_dma_chan *fsl_chan, int size)
+{
+ if (size > 1024)
+ return;
+
+ if (size) {
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
+ | ((__ilog2(size) << 24) & 0x0f000000),
+ 32);
+ fsl_chan->feature |= FSL_DMA_CHAN_PAUSE_EXT;
+ } else
+ fsl_chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT;
+}
+
+/**
+ * fsl_chan_toggle_ext_start - Toggle channel external start status
+ * @fsl_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 fsl_dma_chan *fsl_chan, int enable)
+{
+ if (enable)
+ fsl_chan->feature |= FSL_DMA_CHAN_START_EXT;
+ else
+ fsl_chan->feature &= ~FSL_DMA_CHAN_START_EXT;
+}
+
+static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct fsl_desc_sw *desc = tx_to_fsl_desc(tx);
+ struct fsl_dma_chan *fsl_chan = to_fsl_chan(tx->chan);
+ unsigned long flags;
+ dma_cookie_t cookie;
+
+ /* cookie increment and adding to ld_queue must be atomic */
+ spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+
+ cookie = fsl_chan->common.cookie;
+ cookie++;
+ if (cookie < 0)
+ cookie = 1;
+ desc->async_tx.cookie = cookie;
+ fsl_chan->common.cookie = desc->async_tx.cookie;
+
+ append_ld_queue(fsl_chan, desc);
+ list_splice_init(&desc->async_tx.tx_list, fsl_chan->ld_queue.prev);
+
+ spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+
+ return cookie;
+}
+
+/**
+ * fsl_dma_alloc_descriptor - Allocate descriptor from channel's DMA pool.
+ * @fsl_chan : Freescale DMA channel
+ *
+ * Return - The descriptor allocated. NULL for failed.
+ */
+static struct fsl_desc_sw *fsl_dma_alloc_descriptor(
+ struct fsl_dma_chan *fsl_chan)
+{
+ dma_addr_t pdesc;
+ struct fsl_desc_sw *desc_sw;
+
+ desc_sw = dma_pool_alloc(fsl_chan->desc_pool, GFP_ATOMIC, &pdesc);
+ if (desc_sw) {
+ memset(desc_sw, 0, sizeof(struct fsl_desc_sw));
+ dma_async_tx_descriptor_init(&desc_sw->async_tx,
+ &fsl_chan->common);
+ desc_sw->async_tx.tx_submit = fsl_dma_tx_submit;
+ INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
+ desc_sw->async_tx.phys = pdesc;
+ }
+
+ return desc_sw;
+}
+
+
+/**
+ * fsl_dma_alloc_chan_resources - Allocate resources for DMA channel.
+ * @fsl_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 *chan,
+ struct dma_client *client)
+{
+ struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
+
+ /* Has this channel already been allocated? */
+ if (fsl_chan->desc_pool)
+ return 1;
+
+ /* We need the descriptor to be aligned to 32bytes
+ * for meeting FSL DMA specification requirement.
+ */
+ fsl_chan->desc_pool = dma_pool_create("fsl_dma_engine_desc_pool",
+ fsl_chan->dev, sizeof(struct fsl_desc_sw),
+ 32, 0);
+ if (!fsl_chan->desc_pool) {
+ dev_err(fsl_chan->dev, "No memory for channel %d "
+ "descriptor dma pool.\n", fsl_chan->id);
+ return 0;
+ }
+
+ return 1;
+}
+
+/**
+ * fsl_dma_free_chan_resources - Free all resources of the channel.
+ * @fsl_chan : Freescale DMA channel
+ */
+static void fsl_dma_free_chan_resources(struct dma_chan *chan)
+{
+ struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
+ struct fsl_desc_sw *desc, *_desc;
+ unsigned long flags;
+
+ dev_dbg(fsl_chan->dev, "Free all channel resources.\n");
+ spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+ list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
+#ifdef FSL_DMA_LD_DEBUG
+ dev_dbg(fsl_chan->dev,
+ "LD %p will be released.\n", desc);
+#endif
+ list_del(&desc->node);
+ /* free link descriptor */
+ dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
+ }
+ spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+ dma_pool_destroy(fsl_chan->desc_pool);
+
+ fsl_chan->desc_pool = NULL;
+}
+
+static struct dma_async_tx_descriptor *
+fsl_dma_prep_interrupt(struct dma_chan *chan, unsigned long flags)
+{
+ struct fsl_dma_chan *fsl_chan;
+ struct fsl_desc_sw *new;
+
+ if (!chan)
+ return NULL;
+
+ fsl_chan = to_fsl_chan(chan);
+
+ new = fsl_dma_alloc_descriptor(fsl_chan);
+ if (!new) {
+ dev_err(fsl_chan->dev, "No free memory for link descriptor\n");
+ 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->async_tx.tx_list);
+
+ /* Set End-of-link to the last link descriptor of new list*/
+ set_ld_eol(fsl_chan, new);
+
+ return &new->async_tx;
+}
+
+static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
+ struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
+ size_t len, unsigned long flags)
+{
+ struct fsl_dma_chan *fsl_chan;
+ struct fsl_desc_sw *first = NULL, *prev = NULL, *new;
+ size_t copy;
+ LIST_HEAD(link_chain);
+
+ if (!chan)
+ return NULL;
+
+ if (!len)
+ return NULL;
+
+ fsl_chan = to_fsl_chan(chan);
+
+ do {
+
+ /* Allocate the link descriptor from DMA pool */
+ new = fsl_dma_alloc_descriptor(fsl_chan);
+ if (!new) {
+ dev_err(fsl_chan->dev,
+ "No free memory for link descriptor\n");
+ return NULL;
+ }
+#ifdef FSL_DMA_LD_DEBUG
+ dev_dbg(fsl_chan->dev, "new link desc alloc %p\n", new);
+#endif
+
+ copy = min(len, (size_t)FSL_DMA_BCR_MAX_CNT);
+
+ set_desc_cnt(fsl_chan, &new->hw, copy);
+ set_desc_src(fsl_chan, &new->hw, dma_src);
+ set_desc_dest(fsl_chan, &new->hw, dma_dest);
+
+ if (!first)
+ first = new;
+ else
+ set_desc_next(fsl_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_dest += copy;
+
+ /* Insert the link descriptor to the LD ring */
+ list_add_tail(&new->node, &first->async_tx.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(fsl_chan, new);
+
+ return first ? &first->async_tx : NULL;
+}
+
+/**
+ * fsl_dma_update_completed_cookie - Update the completed cookie.
+ * @fsl_chan : Freescale DMA channel
+ */
+static void fsl_dma_update_completed_cookie(struct fsl_dma_chan *fsl_chan)
+{
+ struct fsl_desc_sw *cur_desc, *desc;
+ dma_addr_t ld_phy;
+
+ ld_phy = get_cdar(fsl_chan) & FSL_DMA_NLDA_MASK;
+
+ if (ld_phy) {
+ cur_desc = NULL;
+ list_for_each_entry(desc, &fsl_chan->ld_queue, node)
+ if (desc->async_tx.phys == ld_phy) {
+ cur_desc = desc;
+ break;
+ }
+
+ if (cur_desc && cur_desc->async_tx.cookie) {
+ if (dma_is_idle(fsl_chan))
+ fsl_chan->completed_cookie =
+ cur_desc->async_tx.cookie;
+ else
+ fsl_chan->completed_cookie =
+ cur_desc->async_tx.cookie - 1;
+ }
+ }
+}
+
+/**
+ * fsl_chan_ld_cleanup - Clean up link descriptors
+ * @fsl_chan : Freescale DMA channel
+ *
+ * This function clean up the ld_queue of DMA channel.
+ * If 'in_intr' is set, the function will move the link descriptor to
+ * the recycle list. Otherwise, free it directly.
+ */
+static void fsl_chan_ld_cleanup(struct fsl_dma_chan *fsl_chan)
+{
+ struct fsl_desc_sw *desc, *_desc;
+ unsigned long flags;
+
+ spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+
+ dev_dbg(fsl_chan->dev, "chan completed_cookie = %d\n",
+ fsl_chan->completed_cookie);
+ list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
+ dma_async_tx_callback callback;
+ void *callback_param;
+
+ if (dma_async_is_complete(desc->async_tx.cookie,
+ fsl_chan->completed_cookie, fsl_chan->common.cookie)
+ == DMA_IN_PROGRESS)
+ break;
+
+ callback = desc->async_tx.callback;
+ callback_param = desc->async_tx.callback_param;
+
+ /* Remove from ld_queue list */
+ list_del(&desc->node);
+
+ dev_dbg(fsl_chan->dev, "link descriptor %p will be recycle.\n",
+ desc);
+ dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
+
+ /* Run the link descriptor callback function */
+ if (callback) {
+ spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+ dev_dbg(fsl_chan->dev, "link descriptor %p callback\n",
+ desc);
+ callback(callback_param);
+ spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+ }
+ }
+ spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+}
+
+/**
+ * fsl_chan_xfer_ld_queue - Transfer link descriptors in channel ld_queue.
+ * @fsl_chan : Freescale DMA channel
+ */
+static void fsl_chan_xfer_ld_queue(struct fsl_dma_chan *fsl_chan)
+{
+ struct list_head *ld_node;
+ dma_addr_t next_dest_addr;
+ unsigned long flags;
+
+ if (!dma_is_idle(fsl_chan))
+ return;
+
+ dma_halt(fsl_chan);
+
+ /* If there are some link descriptors
+ * not transfered in queue. We need to start it.
+ */
+ spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+
+ /* Find the first un-transfer desciptor */
+ for (ld_node = fsl_chan->ld_queue.next;
+ (ld_node != &fsl_chan->ld_queue)
+ && (dma_async_is_complete(
+ to_fsl_desc(ld_node)->async_tx.cookie,
+ fsl_chan->completed_cookie,
+ fsl_chan->common.cookie) == DMA_SUCCESS);
+ ld_node = ld_node->next);
+
+ spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+
+ if (ld_node != &fsl_chan->ld_queue) {
+ /* Get the ld start address from ld_queue */
+ next_dest_addr = to_fsl_desc(ld_node)->async_tx.phys;
+ dev_dbg(fsl_chan->dev, "xfer LDs staring from %p\n",
+ (void *)next_dest_addr);
+ set_cdar(fsl_chan, next_dest_addr);
+ dma_start(fsl_chan);
+ } else {
+ set_cdar(fsl_chan, 0);
+ set_ndar(fsl_chan, 0);
+ }
+}
+
+/**
+ * fsl_dma_memcpy_issue_pending - Issue the DMA start command
+ * @fsl_chan : Freescale DMA channel
+ */
+static void fsl_dma_memcpy_issue_pending(struct dma_chan *chan)
+{
+ struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
+
+#ifdef FSL_DMA_LD_DEBUG
+ struct fsl_desc_sw *ld;
+ unsigned long flags;
+
+ spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+ if (list_empty(&fsl_chan->ld_queue)) {
+ spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+ return;
+ }
+
+ dev_dbg(fsl_chan->dev, "--memcpy issue--\n");
+ list_for_each_entry(ld, &fsl_chan->ld_queue, node) {
+ int i;
+ dev_dbg(fsl_chan->dev, "Ch %d, LD %08x\n",
+ fsl_chan->id, ld->async_tx.phys);
+ for (i = 0; i < 8; i++)
+ dev_dbg(fsl_chan->dev, "LD offset %d: %08x\n",
+ i, *(((u32 *)&ld->hw) + i));
+ }
+ dev_dbg(fsl_chan->dev, "----------------\n");
+ spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+#endif
+
+ fsl_chan_xfer_ld_queue(fsl_chan);
+}
+
+/**
+ * fsl_dma_is_complete - Determine the DMA status
+ * @fsl_chan : Freescale DMA channel
+ */
+static enum dma_status fsl_dma_is_complete(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ dma_cookie_t *done,
+ dma_cookie_t *used)
+{
+ struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
+ dma_cookie_t last_used;
+ dma_cookie_t last_complete;
+
+ fsl_chan_ld_cleanup(fsl_chan);
+
+ last_used = chan->cookie;
+ last_complete = fsl_chan->completed_cookie;
+
+ if (done)
+ *done = last_complete;
+
+ if (used)
+ *used = last_used;
+
+ return dma_async_is_complete(cookie, last_complete, last_used);
+}
+
+static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
+{
+ struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
+ u32 stat;
+ int update_cookie = 0;
+ int xfer_ld_q = 0;
+
+ stat = get_sr(fsl_chan);
+ dev_dbg(fsl_chan->dev, "event: channel %d, stat = 0x%x\n",
+ fsl_chan->id, stat);
+ set_sr(fsl_chan, stat); /* Clear the event register */
+
+ stat &= ~(FSL_DMA_SR_CB | FSL_DMA_SR_CH);
+ if (!stat)
+ return IRQ_NONE;
+
+ if (stat & FSL_DMA_SR_TE)
+ dev_err(fsl_chan->dev, "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) {
+ dev_dbg(fsl_chan->dev, "event: Programming Error INT\n");
+ if (get_bcr(fsl_chan) == 0) {
+ /* BCR register is 0, this is a DMA_INTERRUPT async_tx.
+ * Now, update the completed cookie, and continue the
+ * next uncompleted transfer.
+ */
+ update_cookie = 1;
+ xfer_ld_q = 1;
+ }
+ stat &= ~FSL_DMA_SR_PE;
+ }
+
+ /* If the link descriptor segment transfer finishes,
+ * we will recycle the used descriptor.
+ */
+ if (stat & FSL_DMA_SR_EOSI) {
+ dev_dbg(fsl_chan->dev, "event: End-of-segments INT\n");
+ dev_dbg(fsl_chan->dev, "event: clndar %p, nlndar %p\n",
+ (void *)get_cdar(fsl_chan), (void *)get_ndar(fsl_chan));
+ stat &= ~FSL_DMA_SR_EOSI;
+ update_cookie = 1;
+ }
+
+ /* For MPC8349, EOCDI event need to update cookie
+ * and start the next transfer if it exist.
+ */
+ if (stat & FSL_DMA_SR_EOCDI) {
+ dev_dbg(fsl_chan->dev, "event: End-of-Chain link INT\n");
+ stat &= ~FSL_DMA_SR_EOCDI;
+ update_cookie = 1;
+ xfer_ld_q = 1;
+ }
+
+ /* 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) {
+ dev_dbg(fsl_chan->dev, "event: End-of-link INT\n");
+ stat &= ~FSL_DMA_SR_EOLNI;
+ xfer_ld_q = 1;
+ }
+
+ if (update_cookie)
+ fsl_dma_update_completed_cookie(fsl_chan);
+ if (xfer_ld_q)
+ fsl_chan_xfer_ld_queue(fsl_chan);
+ if (stat)
+ dev_dbg(fsl_chan->dev, "event: unhandled sr 0x%02x\n",
+ stat);
+
+ dev_dbg(fsl_chan->dev, "event: Exit\n");
+ tasklet_schedule(&fsl_chan->tasklet);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t fsl_dma_do_interrupt(int irq, void *data)
+{
+ struct fsl_dma_device *fdev = (struct fsl_dma_device *)data;
+ u32 gsr;
+ int ch_nr;
+
+ gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->reg_base)
+ : in_le32(fdev->reg_base);
+ ch_nr = (32 - ffs(gsr)) / 8;
+
+ return fdev->chan[ch_nr] ? fsl_dma_chan_do_interrupt(irq,
+ fdev->chan[ch_nr]) : IRQ_NONE;
+}
+
+static void dma_do_tasklet(unsigned long data)
+{
+ struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
+ fsl_chan_ld_cleanup(fsl_chan);
+}
+
+static int __devinit fsl_dma_chan_probe(struct fsl_dma_device *fdev,
+ struct device_node *node, u32 feature, const char *compatible)
+{
+ struct fsl_dma_chan *new_fsl_chan;
+ int err;
+
+ /* alloc channel */
+ new_fsl_chan = kzalloc(sizeof(struct fsl_dma_chan), GFP_KERNEL);
+ if (!new_fsl_chan) {
+ dev_err(fdev->dev, "No free memory for allocating "
+ "dma channels!\n");
+ return -ENOMEM;
+ }
+
+ /* get dma channel register base */
+ err = of_address_to_resource(node, 0, &new_fsl_chan->reg);
+ if (err) {
+ dev_err(fdev->dev, "Can't get %s property 'reg'\n",
+ node->full_name);
+ goto err_no_reg;
+ }
+
+ new_fsl_chan->feature = feature;
+
+ if (!fdev->feature)
+ fdev->feature = new_fsl_chan->feature;
+
+ /* If the DMA device's feature is different than its channels',
+ * report the bug.
+ */
+ WARN_ON(fdev->feature != new_fsl_chan->feature);
+
+ new_fsl_chan->dev = &new_fsl_chan->common.dev;
+ new_fsl_chan->reg_base = ioremap(new_fsl_chan->reg.start,
+ new_fsl_chan->reg.end - new_fsl_chan->reg.start + 1);
+
+ new_fsl_chan->id = ((new_fsl_chan->reg.start - 0x100) & 0xfff) >> 7;
+ if (new_fsl_chan->id > FSL_DMA_MAX_CHANS_PER_DEVICE) {
+ dev_err(fdev->dev, "There is no %d channel!\n",
+ new_fsl_chan->id);
+ err = -EINVAL;
+ goto err_no_chan;
+ }
+ fdev->chan[new_fsl_chan->id] = new_fsl_chan;
+ tasklet_init(&new_fsl_chan->tasklet, dma_do_tasklet,
+ (unsigned long)new_fsl_chan);
+
+ /* Init the channel */
+ dma_init(new_fsl_chan);
+
+ /* Clear cdar registers */
+ set_cdar(new_fsl_chan, 0);
+
+ switch (new_fsl_chan->feature & FSL_DMA_IP_MASK) {
+ case FSL_DMA_IP_85XX:
+ new_fsl_chan->toggle_ext_start = fsl_chan_toggle_ext_start;
+ new_fsl_chan->toggle_ext_pause = fsl_chan_toggle_ext_pause;
+ case FSL_DMA_IP_83XX:
+ new_fsl_chan->set_src_loop_size = fsl_chan_set_src_loop_size;
+ new_fsl_chan->set_dest_loop_size = fsl_chan_set_dest_loop_size;
+ }
+
+ spin_lock_init(&new_fsl_chan->desc_lock);
+ INIT_LIST_HEAD(&new_fsl_chan->ld_queue);
+
+ new_fsl_chan->common.device = &fdev->common;
+
+ /* Add the channel to DMA device channel list */
+ list_add_tail(&new_fsl_chan->common.device_node,
+ &fdev->common.channels);
+ fdev->common.chancnt++;
+
+ new_fsl_chan->irq = irq_of_parse_and_map(node, 0);
+ if (new_fsl_chan->irq != NO_IRQ) {
+ err = request_irq(new_fsl_chan->irq,
+ &fsl_dma_chan_do_interrupt, IRQF_SHARED,
+ "fsldma-channel", new_fsl_chan);
+ if (err) {
+ dev_err(fdev->dev, "DMA channel %s request_irq error "
+ "with return %d\n", node->full_name, err);
+ goto err_no_irq;
+ }
+ }
+
+ dev_info(fdev->dev, "#%d (%s), irq %d\n", new_fsl_chan->id,
+ compatible, new_fsl_chan->irq);
+
+ return 0;
+
+err_no_irq:
+ list_del(&new_fsl_chan->common.device_node);
+err_no_chan:
+ iounmap(new_fsl_chan->reg_base);
+err_no_reg:
+ kfree(new_fsl_chan);
+ return err;
+}
+
+static void fsl_dma_chan_remove(struct fsl_dma_chan *fchan)
+{
+ free_irq(fchan->irq, fchan);
+ list_del(&fchan->common.device_node);
+ iounmap(fchan->reg_base);
+ kfree(fchan);
+}
+
+static int __devinit of_fsl_dma_probe(struct of_device *dev,
+ const struct of_device_id *match)
+{
+ int err;
+ struct fsl_dma_device *fdev;
+ struct device_node *child;
+
+ fdev = kzalloc(sizeof(struct fsl_dma_device), GFP_KERNEL);
+ if (!fdev) {
+ dev_err(&dev->dev, "No enough memory for 'priv'\n");
+ return -ENOMEM;
+ }
+ fdev->dev = &dev->dev;
+ INIT_LIST_HEAD(&fdev->common.channels);
+
+ /* get DMA controller register base */
+ err = of_address_to_resource(dev->node, 0, &fdev->reg);
+ if (err) {
+ dev_err(&dev->dev, "Can't get %s property 'reg'\n",
+ dev->node->full_name);
+ goto err_no_reg;
+ }
+
+ dev_info(&dev->dev, "Probe the Freescale DMA driver for %s "
+ "controller at %p...\n",
+ match->compatible, (void *)fdev->reg.start);
+ fdev->reg_base = ioremap(fdev->reg.start, fdev->reg.end
+ - fdev->reg.start + 1);
+
+ dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask);
+ dma_cap_set(DMA_INTERRUPT, 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_is_tx_complete = fsl_dma_is_complete;
+ fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
+ fdev->common.dev = &dev->dev;
+
+ fdev->irq = irq_of_parse_and_map(dev->node, 0);
+ if (fdev->irq != NO_IRQ) {
+ err = request_irq(fdev->irq, &fsl_dma_do_interrupt, IRQF_SHARED,
+ "fsldma-device", fdev);
+ if (err) {
+ dev_err(&dev->dev, "DMA device request_irq error "
+ "with return %d\n", err);
+ goto err;
+ }
+ }
+
+ dev_set_drvdata(&(dev->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(dev->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");
+ }
+
+ dma_async_device_register(&fdev->common);
+ return 0;
+
+err:
+ iounmap(fdev->reg_base);
+err_no_reg:
+ kfree(fdev);
+ return err;
+}
+
+static int of_fsl_dma_remove(struct of_device *of_dev)
+{
+ struct fsl_dma_device *fdev;
+ unsigned int i;
+
+ fdev = dev_get_drvdata(&of_dev->dev);
+
+ dma_async_device_unregister(&fdev->common);
+
+ for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++)
+ if (fdev->chan[i])
+ fsl_dma_chan_remove(fdev->chan[i]);
+
+ if (fdev->irq != NO_IRQ)
+ free_irq(fdev->irq, fdev);
+
+ iounmap(fdev->reg_base);
+
+ kfree(fdev);
+ dev_set_drvdata(&of_dev->dev, NULL);
+
+ return 0;
+}
+
+static struct of_device_id of_fsl_dma_ids[] = {
+ { .compatible = "fsl,eloplus-dma", },
+ { .compatible = "fsl,elo-dma", },
+ {}
+};
+
+static struct of_platform_driver of_fsl_dma_driver = {
+ .name = "fsl-elo-dma",
+ .match_table = of_fsl_dma_ids,
+ .probe = of_fsl_dma_probe,
+ .remove = of_fsl_dma_remove,
+};
+
+static __init int of_fsl_dma_init(void)
+{
+ int ret;
+
+ pr_info("Freescale Elo / Elo Plus DMA driver\n");
+
+ ret = of_register_platform_driver(&of_fsl_dma_driver);
+ if (ret)
+ pr_err("fsldma: failed to register platform driver\n");
+
+ return ret;
+}
+
+static void __exit of_fsl_dma_exit(void)
+{
+ of_unregister_platform_driver(&of_fsl_dma_driver);
+}
+
+subsys_initcall(of_fsl_dma_init);
+module_exit(of_fsl_dma_exit);
+
+MODULE_DESCRIPTION("Freescale Elo / Elo Plus DMA driver");
+MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud