[PATCH v5 2/2] DMAEngine: Add DMAEngine driver based on old MSM ADM DMA APIs
Vinod Koul
vinod.koul at linux.intel.com
Mon Mar 26 03:07:29 EDT 2012
On Thu, 2012-03-22 at 19:53 +0530, Ravi Kumar V wrote:
> Add DMAEngine based driver using the old MSM ADM DMA APIs internally.
> The benefit of this approach is that not all the drivers
> have to get converted to DMAEngine APIs simultaneosly while
typo again!
> both the drivers can stay enabled in the kernel. The client
> drivers using the old MSM APIs directly can now convert to
> DMAEngine one by one.
>
> Signed-off-by: Ravi Kumar V <kumarrav at codeaurora.org>
> ---
> arch/arm/mach-msm/include/mach/dma.h | 35 ++
> drivers/dma/Kconfig | 12 +
> drivers/dma/Makefile | 1 +
> drivers/dma/msm_adm_dma.c | 728 ++++++++++++++++++++++++++++++++++
> 4 files changed, 776 insertions(+), 0 deletions(-)
> create mode 100644 drivers/dma/msm_adm_dma.c
>
> diff --git a/arch/arm/mach-msm/include/mach/dma.h b/arch/arm/mach-msm/include/mach/dma.h
> index 05583f5..95b7b15 100644
> --- a/arch/arm/mach-msm/include/mach/dma.h
> +++ b/arch/arm/mach-msm/include/mach/dma.h
> @@ -18,6 +18,36 @@
> #include <linux/list.h>
> #include <mach/msm_iomap.h>
>
> +#define sg_dma_offset(sg) ((sg)->offset)
> +#define box_dma_row_address(box) ((box)->dma_row_address)
> +#define box_dma_row_len(box) ((box)->dma_row_len)
> +#define box_dma_row_num(box) ((box)->dma_row_num)
> +#define box_dma_row_offset(box) ((box)->dma_row_offset)
> +
> +#define MSM_DMA_CMD_MASK 0x9FFF8
> +#define MSM_DMA_CMD_SHIFT 0
> +#define MSM_BOX_SRC_RLEN_MASK 0xFFFF
> +#define MSM_BOX_SRC_RLEN_SHIFT 16
> +#define MSM_BOX_SRC_RNUM_MASK 0xFFFF
> +#define MSM_BOX_SRC_RNUM_SHIFT 16
> +#define MSM_BOX_SRC_ROFFSET_MASK 0xFFFF
> +#define MSM_BOX_SRC_ROFFSET_SHIFT 16
> +#define MSM_BOX_DST_RLEN_MASK 0xFFFF
> +#define MSM_BOX_DST_RNUM_MASK 0xFFFF
> +#define MSM_BOX_DST_ROFFSET_MASK 0xFFFF
> +#define MSM_BOX_MODE_CMD 0x3
> +
> +enum adm_flush_type {
> + ADM_FORCED_FLUSH,
> + ADM_GRACEFUL_FLUSH,
> +};
> +
> +enum adm_dma_type {
> + ADM_SINGLE_MODE,
> + ADM_SG_MODE,
> + ADM_BOX_MODE,
> +};
> +
> struct msm_dmov_errdata {
> uint32_t flush[6];
> };
> @@ -32,6 +62,11 @@ struct msm_dmov_cmd {
> void *data;
> };
>
> +struct msm_adm_cmd_config {
> + uint32_t num_cmd;
> + uint32_t *cmd_cntrl;
> +};
> +
> #ifndef CONFIG_ARCH_MSM8X60
> void msm_dmov_enqueue_cmd(unsigned id, struct msm_dmov_cmd *cmd);
> void msm_dmov_stop_cmd(unsigned id, struct msm_dmov_cmd *cmd, int graceful);
> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
> index f1a2749..1f99362 100644
> +++ b/drivers/dma/msm_adm_dma.c
> +struct msm_dma_chan {
> + int chan_id;
> + dma_cookie_t completed_cookie;
> + dma_cookie_t error_cookie;
i suspect you haven't updated this to use new cookie helpers
> + spinlock_t lock;
> + struct list_head active_list;
> + struct list_head pending_list;
> + struct dma_chan channel;
> + struct dma_pool *desc_pool;
> + struct device *dev;
> + int max_len;
> + int err;
> + struct tasklet_struct tasklet;
> +};
> +
> +struct msm_dma_device {
> + void __iomem *base;
> + struct device *dev;
> + struct dma_device common;
> + struct msm_dma_chan *chan[MSM_DMA_MAX_CHANS_PER_DEVICE];
> +};
> +
> +struct msm_dma_desc_hw {
> + unsigned int cmd_list_ptr;
> +} __aligned(8);
> +
> +/* Single Item Mode */
> +struct adm_cmd_t {
> + unsigned int cmd_cntrl;
> + unsigned int src;
> + unsigned int dst;
> + unsigned int len;
> +};
> +
> +struct adm_box_cmd_t {
> + uint32_t cmd_cntrl;
> + uint32_t src_row_addr;
> + uint32_t dst_row_addr;
> + uint32_t src_dst_len;
> + uint32_t num_rows;
> + uint32_t row_offset;
> +};
> +
> +struct msm_dma_desc_sw {
> + struct msm_dma_desc_hw hw;
> + struct adm_cmd_t *vaddr_cmd;
> + struct adm_box_cmd_t *vaddr_box_cmd;
> + size_t coherent_size;
> + dma_addr_t paddr_cmd_list;
> + struct list_head node;
> + struct msm_dmov_cmd dmov_cmd;
> + struct dma_async_tx_descriptor async_tx;
> +} __aligned(8);
> +
> +static int msm_dma_alloc_chan_resources(struct dma_chan *dchan)
> +{
> + struct msm_dma_chan *chan = to_msm_chan(dchan);
> +
> + /* Has this channel already been allocated? */
> + if (chan->desc_pool)
> + return 1;
> +
> + /*
> + * We need the descriptor to be aligned to 8bytes
> + * for meeting ADM specification requirement.
> + */
> + chan->desc_pool = dma_pool_create("msm_dma_desc_pool",
> + chan->dev,
> + sizeof(struct msm_dma_desc_sw),
> + __alignof__(struct msm_dma_desc_sw), 0);
> + if (!chan->desc_pool) {
> + dev_err(chan->dev, "unable to allocate channel %d "
> + "descriptor pool\n", chan->chan_id);
> + return -ENOMEM;
> + }
> +
> + chan->completed_cookie = 1;
> + dchan->cookie = 1;
rightly guessed...
> +
> + /* there is at least one descriptor free to be allocated */
> + return 1;
hrm?
You need to return the number of descriptors you allocate. And then why
1 here?
> +}
> +
> +static void msm_dma_free_chan_resources(struct dma_chan *dchan)
> +{
> + struct msm_dma_chan *chan = to_msm_chan(dchan);
> + unsigned long flags;
> +
> + dev_dbg(chan->dev, "Free all channel resources.\n");
> + spin_lock_irqsave(&chan->lock, flags);
> + msm_dma_free_desc_list(chan, &chan->active_list);
> + msm_dma_free_desc_list(chan, &chan->pending_list);
Shouldnt you check if dma is active?
> + spin_unlock_irqrestore(&chan->lock, flags);
> +
> + dma_pool_destroy(chan->desc_pool);
> + chan->desc_pool = NULL;
> +}
> +
> +static enum dma_status msm_dma_desc_status(struct msm_dma_chan *chan,
> + struct msm_dma_desc_sw *desc)
> +{
> + return dma_async_is_complete(desc->async_tx.cookie,
> + chan->completed_cookie,
> + chan->channel.cookie);
> +}
> +
> +static void msm_chan_desc_cleanup(struct msm_dma_chan *chan)
> +{
> + struct msm_dma_desc_sw *desc, *_desc;
> + unsigned long flags;
> +
> + dev_dbg(chan->dev, "Cleaning completed descriptor of channel %d\n",
> + chan->chan_id);
> + spin_lock_irqsave(&chan->lock, flags);
> +
> + list_for_each_entry_safe(desc, _desc, &chan->active_list, node) {
> + dma_async_tx_callback callback;
> + void *callback_param;
> +
> + if (msm_dma_desc_status(chan, desc) == DMA_IN_PROGRESS)
> + break;
> +
> + /* Remove from the list of running transactions */
> + list_del(&desc->node);
> +
> + /* Run the link descriptor callback function */
> + callback = desc->async_tx.callback;
> + callback_param = desc->async_tx.callback_param;
> + if (callback) {
> + spin_unlock_irqrestore(&chan->lock, flags);
> + callback(callback_param);
> + spin_lock_irqsave(&chan->lock, flags);
> + }
> +
> + /* Run any dependencies, then free the descriptor */
> + dma_run_dependencies(&desc->async_tx);
> + spin_unlock_irqrestore(&chan->lock, flags);
> +
> + if (desc->vaddr_cmd) {
> + dma_free_coherent(chan->dev, desc->coherent_size,
> + (void *)desc->vaddr_cmd,
> + desc->paddr_cmd_list);
> + } else {
> + dma_free_coherent(chan->dev, desc->coherent_size,
> + (void *)desc->vaddr_box_cmd,
> + desc->paddr_cmd_list);
> + }
> + spin_lock_irqsave(&chan->lock, flags);
> + dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
> + }
> +
> + spin_unlock_irqrestore(&chan->lock, flags);
> +}
> +
> +static void dma_do_tasklet(unsigned long data)
> +{
> + struct msm_dma_chan *chan = (struct msm_dma_chan *)data;
> + msm_chan_desc_cleanup(chan);
> +}
> +
> +static void
> +msm_dma_complete_func(struct msm_dmov_cmd *cmd,
> + unsigned int result,
> + struct msm_dmov_errdata *err)
> +{
> + unsigned long flags;
> + struct msm_dma_desc_sw *desch = container_of(cmd,
> + struct msm_dma_desc_sw, dmov_cmd);
> + struct msm_dma_chan *chan = to_msm_chan(desch->async_tx.chan);
> +
> + spin_lock_irqsave(&chan->lock, flags);
> +
> + if ((result != NO_ERR_CHAN_STATUS) && err)
> + chan->error_cookie = desch->async_tx.cookie;
> + chan->completed_cookie = desch->async_tx.cookie;
> +
> + tasklet_schedule(&chan->tasklet);
> +
> + spin_unlock_irqrestore(&chan->lock, flags);
> +}
> +
> +/*
> + * Passes transfer descriptors to DMA hardware.
> + */
> +static void msm_dma_issue_pending(struct dma_chan *dchan)
> +{
> + struct msm_dma_chan *chan = to_msm_chan(dchan);
> + struct msm_dma_desc_sw *desch;
> + unsigned long flags;
> +
> + if (chan->err)
> + return;
> +
> + spin_lock_irqsave(&chan->lock, flags);
> +
> + if (list_empty(&chan->pending_list))
> + goto out_unlock;
> +
> + desch = list_first_entry(&chan->pending_list, struct msm_dma_desc_sw,
> + node);
> + list_del(&desch->node);
> + desch->dmov_cmd.complete_func = msm_dma_complete_func;
> + desch->dmov_cmd.execute_func = NULL;
> + desch->dmov_cmd.cmdptr = DMOV_CMD_ADDR(desch->async_tx.phys);
> + list_add_tail(&desch->node, &chan->active_list);
> + mb();
> + msm_dmov_enqueue_cmd(chan->chan_id, &desch->dmov_cmd);
> +out_unlock:
> + spin_unlock_irqrestore(&chan->lock, flags);
> +}
> +
> +/*
> + * Assignes cookie for each transfer descriptor passed.
> + * Returns
> + * Assigend cookie for success.
> + * Error value for failure.
> + */
> +static dma_cookie_t msm_dma_tx_submit(struct dma_async_tx_descriptor *tx)
> +{
> + struct msm_dma_chan *chan = to_msm_chan(tx->chan);
> + struct msm_dma_desc_sw *desc = container_of(tx,
> + struct msm_dma_desc_sw, async_tx);
> + unsigned long flags;
> + dma_cookie_t cookie = -EBUSY;
> +
> + if (chan->err)
> + return cookie;
> +
> + spin_lock_irqsave(&chan->lock, flags);
> +
> + /*
> + * assign cookies to all of the software descriptors
> + * that make up this transaction
> + */
> + cookie = chan->channel.cookie;
> + cookie++;
> + if (cookie < 0)
> + cookie = DMA_MIN_COOKIE;
this needs update
> +
> + desc->async_tx.cookie = cookie;
> + chan->channel.cookie = cookie;
> +
> + /* put this transaction onto the tail of the pending queue */
> + list_add_tail(&desc->node, &chan->pending_list);
> +
> + spin_unlock_irqrestore(&chan->lock, flags);
> +
> + return cookie;
> +}
> +
> +/*
> + * Returns the DMA transfer status of a particular cookie
> + */
> +static enum dma_status msm_tx_status(struct dma_chan *dchan,
> + dma_cookie_t cookie,
> + struct dma_tx_state *txstate)
> +{
> + struct msm_dma_chan *chan = to_msm_chan(dchan);
> + dma_cookie_t last_used;
> + dma_cookie_t last_complete;
> + enum dma_status status;
> +
> + last_used = dchan->cookie;
> + last_complete = chan->completed_cookie;
> +
> + dma_set_tx_state(txstate, last_complete, last_used, 0);
> +
> + status = dma_async_is_complete(cookie, last_complete, last_used);
> +
> + if (status != DMA_IN_PROGRESS)
> + if (chan->error_cookie == cookie)
> + status = DMA_ERROR;
> +
> + return status;
> +}
same here
> +
> +static struct msm_dma_desc_sw *msm_dma_alloc_descriptor(
> + struct msm_dma_chan *chan,
> + int cmd_cnt,
> + enum adm_dma_type mask)
> +{
> + struct msm_dma_desc_sw *desc;
> + dma_addr_t pdesc_addr;
> + dma_addr_t paddr_cmd_list;
> + void *err = NULL;
> +
> + desc = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &pdesc_addr);
why atomic?
> + if (!desc) {
> + dev_dbg(chan->dev, "out of memory for desc\n");
> + return ERR_CAST(desc);
> + }
> +
> + memset(desc, 0, sizeof(*desc));
> + desc->async_tx.phys = pdesc_addr;
> +
> + if (mask == ADM_BOX_MODE) {
> + desc->coherent_size = sizeof(struct adm_box_cmd_t);
> + desc->vaddr_box_cmd = dma_alloc_coherent(chan->dev,
> + sizeof(struct adm_box_cmd_t),
> + &paddr_cmd_list, GFP_ATOMIC);
> + if (!desc->vaddr_box_cmd) {
> + dev_dbg(chan->dev, "out of memory for desc\n");
> + err = desc->vaddr_box_cmd;
> + goto fail;
> + }
> + } else {
> + desc->coherent_size = sizeof(struct adm_cmd_t)*cmd_cnt;
> +
> + desc->vaddr_cmd = dma_alloc_coherent(chan->dev,
> + sizeof(struct adm_cmd_t)*cmd_cnt,
> + &paddr_cmd_list, GFP_ATOMIC);
> +
> + if (!desc->vaddr_cmd) {
> + dev_dbg(chan->dev, "out of memory for desc\n");
> + err = desc->vaddr_cmd;
> + goto fail;
> + }
> + }
> +
> + dma_async_tx_descriptor_init(&desc->async_tx, &chan->channel);
> + desc->async_tx.tx_submit = msm_dma_tx_submit;
> + desc->paddr_cmd_list = paddr_cmd_list;
> + desc->hw.cmd_list_ptr = (paddr_cmd_list >> 3) | CMD_PTR_LP;
> + return desc;
> +fail:
> + dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
> + return ERR_CAST(err);
> +}
> +
> +/*
> + * Prepares the transfer descriptors for SG transaction.
> + * Returns
> + * address of dma_async_tx_descriptor for success.
> + * Pointer of error value for failure.
Kernel style is to use kernel-doc for this kind of description
> + */
> +static struct dma_async_tx_descriptor *msm_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, void *context)
> +{
> +
> + struct msm_dma_chan *chan;
> + struct msm_dma_desc_sw *new;
> + size_t copy, len;
> + int cmd_cnt = 0;
> + int first = 0;
> + int i;
> + dma_addr_t src;
> + dma_addr_t dst;
> + struct adm_cmd_t *cmdlist_vaddr;
> + struct scatterlist *sg;
> + struct msm_adm_cmd_config *cmd_config = context;
> +
> + if (!dchan)
> + return NULL;
> +
> + if (dst_nents == 0 || src_nents == 0)
> + return NULL;
> + if (!dst_sg || !src_sg)
> + return NULL;
> +
> + if ((dst_nents != src_nents) || (cmd_config->num_cmd != src_nents))
> + return NULL;
> +
> + chan = to_msm_chan(dchan);
> +
> + cmd_cnt = src_nents;
> + for (i = 0; i < src_nents; i++) {
> + len = sg_dma_len(src_sg + i);
> + if (len != MAX_TRANSFER_LENGTH)
> + cmd_cnt += len/MAX_TRANSFER_LENGTH;
> + }
> +
> + new = msm_dma_alloc_descriptor(chan, cmd_cnt, ADM_SG_MODE);
> +
> + if (!new) {
> + dev_err(chan->dev,
> + "No free memory for link descriptor\n");
> + return NULL;
> + }
> +
> + cmdlist_vaddr = new->vaddr_cmd;
> +
> + for_each_sg(src_sg, sg, src_nents, i) {
> + len = sg_dma_len(sg);
> + src = sg_dma_address(sg);
> + do {
> + copy = (len >= MAX_TRANSFER_LENGTH) ?
> + MAX_TRANSFER_LENGTH : len;
> + cmdlist_vaddr->src = src;
> + cmdlist_vaddr->len = copy;
> + cmdlist_vaddr->cmd_cntrl =
> + *(cmd_config->cmd_cntrl + i) &
> + MSM_DMA_CMD_MASK;
> + if (first == 0) {
> + if (cmd_cnt == 1)
> + cmdlist_vaddr->cmd_cntrl |= CMD_LC;
> + else
> + cmdlist_vaddr->cmd_cntrl |= CMD_OCB;
> + first = 1;
> + }
> + cmdlist_vaddr++;
> + len -= copy;
> + src += copy;
> + } while (len);
> + }
> + if (cmd_cnt > 1) {
> + cmdlist_vaddr--;
> + cmdlist_vaddr->cmd_cntrl |= CMD_LC | CMD_OCU;
> + }
> +
> + cmdlist_vaddr = new->vaddr_cmd;
> +
> + for_each_sg(dst_sg, sg, src_nents, i) {
> + len = sg_dma_len(sg);
> + dst = sg_dma_address(sg);
> + do {
> + copy = (len >= MAX_TRANSFER_LENGTH) ?
> + MAX_TRANSFER_LENGTH : len;
> + cmdlist_vaddr->dst = dst;
> + cmdlist_vaddr++;
> + len -= copy;
> + dst += copy;
> + } while (len);
> +
> + }
> +
> +#ifdef DEBUG
> + cmdlist_vaddr = new->vaddr_cmd;
> + i = 0;
> + do {
> + dev_dbg(chan->dev, "cmd %d src 0x%x dst 0x%x len 0x%x "
> + "cntrl 0x%x\n",
> + i, cmdlist_vaddr->src, cmdlist_vaddr->dst,
> + cmdlist_vaddr->len, cmdlist_vaddr->cmd_cntrl);
> + cmdlist_vaddr++;
> + } while (!((cmdlist_vaddr-1)->cmd_cntrl & CMD_LC));
> +#endif
> + new->async_tx.flags = flags;
> + new->async_tx.cookie = -EBUSY;
> +
> + return &new->async_tx;
> +}
> +
> +/*
> + * Controlling the hardware channel like stopping, flushing.
> + */
> +static int msm_dma_chan_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
> + unsigned long arg)
> +{
> + enum adm_flush_type cmd_type = arg;
> +
> + if (cmd == DMA_TERMINATE_ALL) {
> + switch (cmd_type) {
> + case ADM_GRACEFUL_FLUSH:
> + msm_dmov_stop_cmd(chan->chan_id, NULL, 1);
> + break;
> + case ADM_FORCED_FLUSH:
> + /*
> + * We treate default as forced flush
> + * so we fall through
> + */
> + default:
> + msm_dmov_stop_cmd(chan->chan_id, NULL, 0);
> + break;
> + }
> + }
No slave? How do you pass the peripheral properties like addr etc?
> + return 0;
> +}
> +
> +MODULE_DESCRIPTION("Qualcomm DMA driver");
> +MODULE_LICENSE("GPL v2");
MODULE_ALIAS, OWNER, AUTHOR pls
--
~Vinod
More information about the linux-arm-kernel
mailing list