On Sat, May 1, 2010 at 11:44 PM, Ohad Ben-Cohen <ohad@xxxxxxxxxx> wrote:
> Instead of using low level cache manipulation API,
> use the standard DMA API. This changes the concept
> of the dspbridge cache API a little, hence the naming changes:
> * Flush marks the beginning of a DMA transfer from the MPU
> to the DSP.
> * Invalidate marks the beginning of a DMA transfer from the DSP
> to the MPU.
>
> Both of these actions eventually build a scatter gatter list
> using the page information that was kept during proc_map,
> and feed it to the standard dma_map_sg API.
> Note that now users cannot manipulate the cache state of any random
> address; if the buffer is not part of a previous memory mapping of that
> application, the request is denied.
>
> Signed-off-by: Ohad Ben-Cohen <ohad@xxxxxxxxxx>
> ---
> If you want, you can also reach me at < ohadb at ti dot com >.
>
> arch/arm/plat-omap/include/dspbridge/_dcd.h | 4 +-
> arch/arm/plat-omap/include/dspbridge/proc.h | 4 +-
> arch/arm/plat-omap/include/dspbridge/wcdioctl.h | 4 +-
> drivers/dsp/bridge/pmgr/wcd.c | 12 +-
> drivers/dsp/bridge/rmgr/proc.c | 152 ++++++++++++++++++-----
> 5 files changed, 134 insertions(+), 42 deletions(-)
>
> diff --git a/arch/arm/plat-omap/include/dspbridge/_dcd.h b/arch/arm/plat-omap/include/dspbridge/_dcd.h
> index 1350feb..0af4a31 100644
> --- a/arch/arm/plat-omap/include/dspbridge/_dcd.h
> +++ b/arch/arm/plat-omap/include/dspbridge/_dcd.h
> @@ -110,9 +110,9 @@ extern u32 procwrap_reserve_memory(union Trapped_Args *args, void *pr_ctxt);
> extern u32 procwrap_un_reserve_memory(union Trapped_Args *args, void *pr_ctxt);
> extern u32 procwrap_map(union Trapped_Args *args, void *pr_ctxt);
> extern u32 procwrap_un_map(union Trapped_Args *args, void *pr_ctxt);
> -extern u32 procwrap_flush_memory(union Trapped_Args *args, void *pr_ctxt);
> +extern u32 procwrap_begin_dma_to_dsp(union Trapped_Args *args, void *pr_ctxt);
> extern u32 procwrap_stop(union Trapped_Args *args, void *pr_ctxt);
> -extern u32 procwrap_invalidate_memory(union Trapped_Args *args, void *pr_ctxt);
> +extern u32 procwrap_begin_dma_from_dsp(union Trapped_Args *args, void *pr_ctxt);
>
> /* NODE wrapper functions */
> extern u32 nodewrap_allocate(union Trapped_Args *args, void *pr_ctxt);
> diff --git a/arch/arm/plat-omap/include/dspbridge/proc.h b/arch/arm/plat-omap/include/dspbridge/proc.h
> index 0707739..f8450a6 100644
> --- a/arch/arm/plat-omap/include/dspbridge/proc.h
> +++ b/arch/arm/plat-omap/include/dspbridge/proc.h
> @@ -472,7 +472,7 @@ extern dsp_status proc_stop(void *hprocessor);
> * Details:
> * All the arguments are currently ignored.
> */
> -extern dsp_status proc_flush_memory(void *hprocessor,
> +extern dsp_status proc_begin_dma_to_dsp(void *hprocessor,
> void *pmpu_addr, u32 ul_size, u32 ul_flags);
>
> /*
> @@ -493,7 +493,7 @@ extern dsp_status proc_flush_memory(void *hprocessor,
> * Details:
> * All the arguments are currently ignored.
> */
> -extern dsp_status proc_invalidate_memory(void *hprocessor,
> +extern dsp_status proc_begin_dma_from_dsp(void *hprocessor,
> void *pmpu_addr, u32 ul_size);
>
> /*
> diff --git a/arch/arm/plat-omap/include/dspbridge/wcdioctl.h b/arch/arm/plat-omap/include/dspbridge/wcdioctl.h
> index b6a4dda..aba2078 100644
> --- a/arch/arm/plat-omap/include/dspbridge/wcdioctl.h
> +++ b/arch/arm/plat-omap/include/dspbridge/wcdioctl.h
> @@ -452,9 +452,9 @@ union Trapped_Args {
> #define PROC_UNRSVMEM _IOW(DB, DB_IOC(DB_PROC, 11), unsigned long)
> #define PROC_MAPMEM _IOWR(DB, DB_IOC(DB_PROC, 12), unsigned long)
> #define PROC_UNMAPMEM _IOR(DB, DB_IOC(DB_PROC, 13), unsigned long)
> -#define PROC_FLUSHMEMORY _IOW(DB, DB_IOC(DB_PROC, 14), unsigned long)
> +#define PROC_BEGINDMATODSP _IOW(DB, DB_IOC(DB_PROC, 14), unsigned long)
> #define PROC_STOP _IOWR(DB, DB_IOC(DB_PROC, 15), unsigned long)
> -#define PROC_INVALIDATEMEMORY _IOW(DB, DB_IOC(DB_PROC, 16), unsigned long)
> +#define PROC_BEGINDMAFROMDSP _IOW(DB, DB_IOC(DB_PROC, 16), unsigned long)
>
> /* NODE Module */
> #define NODE_ALLOCATE _IOWR(DB, DB_IOC(DB_NODE, 0), unsigned long)
> diff --git a/drivers/dsp/bridge/pmgr/wcd.c b/drivers/dsp/bridge/pmgr/wcd.c
> index 15a05a6..89243f1 100644
> --- a/drivers/dsp/bridge/pmgr/wcd.c
> +++ b/drivers/dsp/bridge/pmgr/wcd.c
> @@ -111,9 +111,9 @@ static struct wcd_cmd proc_cmd[] = {
> {procwrap_un_reserve_memory}, /* PROC_UNRSVMEM */
> {procwrap_map}, /* PROC_MAPMEM */
> {procwrap_un_map}, /* PROC_UNMAPMEM */
> - {procwrap_flush_memory}, /* PROC_FLUSHMEMORY */
> + {procwrap_begin_dma_to_dsp}, /* PROC_BEGINDMATODSP */
> {procwrap_stop}, /* PROC_STOP */
> - {procwrap_invalidate_memory}, /* PROC_INVALIDATEMEMORY */
> + {procwrap_begin_dma_from_dsp}, /* PROC_BEGINDMAFROMDSP */
> };
>
> /* NODE wrapper functions */
> @@ -680,7 +680,7 @@ u32 procwrap_enum_node_info(union Trapped_Args *args, void *pr_ctxt)
> /*
> * ======== procwrap_flush_memory ========
> */
> -u32 procwrap_flush_memory(union Trapped_Args *args, void *pr_ctxt)
> +u32 procwrap_begin_dma_to_dsp(union Trapped_Args *args, void *pr_ctxt)
> {
> dsp_status status;
>
> @@ -688,7 +688,7 @@ u32 procwrap_flush_memory(union Trapped_Args *args, void *pr_ctxt)
> PROC_WRITEBACK_INVALIDATE_MEM)
> return DSP_EINVALIDARG;
>
> - status = proc_flush_memory(args->args_proc_flushmemory.hprocessor,
> + status = proc_begin_dma_to_dsp(args->args_proc_flushmemory.hprocessor,
> args->args_proc_flushmemory.pmpu_addr,
> args->args_proc_flushmemory.ul_size,
> args->args_proc_flushmemory.ul_flags);
> @@ -698,12 +698,12 @@ u32 procwrap_flush_memory(union Trapped_Args *args, void *pr_ctxt)
> /*
> * ======== procwrap_invalidate_memory ========
> */
> -u32 procwrap_invalidate_memory(union Trapped_Args *args, void *pr_ctxt)
> +u32 procwrap_begin_dma_from_dsp(union Trapped_Args *args, void *pr_ctxt)
> {
> dsp_status status;
>
> status =
> - proc_invalidate_memory(args->args_proc_invalidatememory.hprocessor,
> + proc_begin_dma_from_dsp(args->args_proc_invalidatememory.hprocessor,
> args->args_proc_invalidatememory.pmpu_addr,
> args->args_proc_invalidatememory.ul_size);
> return status;
> diff --git a/drivers/dsp/bridge/rmgr/proc.c b/drivers/dsp/bridge/rmgr/proc.c
> index bbc7e0f..8a76681 100644
> --- a/drivers/dsp/bridge/rmgr/proc.c
> +++ b/drivers/dsp/bridge/rmgr/proc.c
> @@ -18,6 +18,8 @@
>
> /* ------------------------------------ Host OS */
> #include <linux/list.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/scatterlist.h>
> #include <linux/spinlock.h>
> #include <dspbridge/host_os.h>
>
> @@ -80,6 +82,7 @@
> #define WBUF 0x8000 /* Output Buffer */
>
> extern char *iva_img;
> +extern struct device *bridge;
>
> /* ----------------------------------- Globals */
>
> @@ -110,6 +113,18 @@ struct proc_object {
> spinlock_t maps_lock;
> };
>
> +/* used to cache dma mapping information */
> +struct bridge_dma_map_info {
> + /* direction of DMA in action, or DMA_NONE */
> + enum dma_data_direction dir;
> + /* number of elements requested by us */
> + int num_pages;
> + /* number of elements returned from dma_map_sg */
> + int sg_num;
> + /* list of buffers used in this DMA action */
> + struct scatterlist *sg;
> +};
> +
> /* used to cache memory mapping information */
> struct memory_map_info {
> struct list_head node;
> @@ -118,6 +133,7 @@ struct memory_map_info {
> u32 dsp_addr;
> u32 size;
> u32 num_usr_pgs;
> + struct bridge_dma_map_info dma_info;
> };
>
> static u32 refs;
> @@ -130,7 +146,23 @@ static s32 get_envp_count(char **envp);
> static char **prepend_envp(char **new_envp, char **envp, s32 envp_elems,
> s32 cnew_envp, char *szVar);
>
> -/* remember mapping information */
> +/* Mapping and Page info caching
> + *
> + * The map_info mechanism is built to remember the (struct page *)
> + * pointers of all pages per a specific memory mapping of a specific
> + * process.
> + * Whenever a memory area is mapped, get_user_pages is used to pin the
> + * relevant pages in memory. As a result of running get_user_pages,
> + * we get the pointers to the page structures, which we now keep in
> + * the memory_map_info struct.
> + * Then, any time the user (the MM application) intends to begin
> + * a DMA (Direct Memory Access) operation to/from the remote processor,
> + * we use this cached page information to build a scatter gatter list
> + * which is given to the standard DMA API (which takes care of low
> + * level cache manipulation).
> + * Currently a simple linked list is used to cache the memory mapping
> + * info per process. This can be further optimized if needed.
> + */
> static struct memory_map_info *add_mapping_info(struct proc_object *pr_obj,
> u32 mpu_addr, u32 dsp_addr, u32 size)
> {
> @@ -197,6 +229,7 @@ static void remove_mapping_information(struct proc_object *pr_obj,
> if (match_exact_map_info(map_info, dsp_addr, size)) {
> pr_debug("%s: match, deleting map info\n", __func__);
> list_del(&map_info->node);
> + kfree(map_info->dma_info.sg);
> kfree(map_info->pages);
> kfree(map_info);
> goto out;
> @@ -625,50 +658,109 @@ dsp_status proc_enum_nodes(void *hprocessor, void **node_tab,
> return status;
> }
>
> -/* Cache operation against kernel address instead of users */
> -static int memory_sync_page(struct memory_map_info *map_info,
> - unsigned long start, ssize_t len, enum dsp_flushtype ftype)
> +static int build_dma_sg(struct memory_map_info *map_info, unsigned long start,
> + ssize_t len, int pg_i)
> {
> struct page *page;
> - void *kaddr;
> unsigned long offset;
> ssize_t rest;
> - int pg_i;
> -
> - pg_i = find_first_page_in_cache(map_info, start);
> - if (pg_i < 0) {
> - pr_err("%s: failed to find first page in cache\n", __func__);
> - return -EINVAL;
> - }
> + int ret = 0, i = 0;
> + struct scatterlist *sg = map_info->dma_info.sg;
>
> while (len) {
> page = get_mapping_page(map_info, pg_i);
> if (!page) {
> pr_err("%s: no page for %08lx\n", __func__, start);
> - return -EINVAL;
> + ret = -EINVAL;
> + goto out;
> } else if (IS_ERR(page)) {
> pr_err("%s: err page for %08lx(%lu)\n", __func__, start,
> PTR_ERR(page));
> - return PTR_ERR(page);
> + ret = PTR_ERR(page);
> + goto out;
> }
>
> offset = start & ~PAGE_MASK;
> - kaddr = kmap(page) + offset;
> rest = min_t(ssize_t, PAGE_SIZE - offset, len);
> - mem_flush_cache(kaddr, rest, ftype);
as a result, we can now have this as well:
diff --git a/arch/arm/plat-omap/include/dspbridge/mem.h
b/arch/arm/plat-omap/include/
index 087f69f..4d9b33b 100644
--- a/arch/arm/plat-omap/include/dspbridge/mem.h
+++ b/arch/arm/plat-omap/include/dspbridge/mem.h
@@ -124,21 +124,6 @@ extern void *mem_calloc(IN u32 byte_size, IN enum
mem_poolattrs
extern void mem_exit(void);
/*
- * ======== mem_flush_cache ========
- * Purpose:
- * Performs system cache sync with discard
- * Parameters:
- * pMemBuf: Pointer to memory region to be flushed.
- * pMemBuf: Size of the memory region to be flushed.
- * Returns:
- * Requires:
- * MEM is initialized.
- * Ensures:
- * Cache is synchronized
- */
-extern void mem_flush_cache(void *pMemBuf, u32 byte_size, s32 FlushType);
-
-/*
* ======== mem_free_phys_mem ========
* Purpose:
* Free the given block of physically contiguous memory.
diff --git a/drivers/dsp/bridge/services/mem.c
b/drivers/dsp/bridge/services/mem.c
index 916a49f..dfb17cf 100644
--- a/drivers/dsp/bridge/services/mem.c
+++ b/drivers/dsp/bridge/services/mem.c
@@ -212,39 +212,6 @@ void mem_exit(void)
}
/*
- * ======== mem_flush_cache ========
- * Purpose:
- * Flush cache
- */
-void mem_flush_cache(void *pMemBuf, u32 byte_size, s32 FlushType)
-{
- if (!pMemBuf)
- return;
-
- switch (FlushType) {
- /* invalidate only */
- case PROC_INVALIDATE_MEM:
- dmac_inv_range(pMemBuf, pMemBuf + byte_size);
- outer_inv_range(__pa((u32) pMemBuf), __pa((u32) pMemBuf +
- byte_size));
- break;
- /* writeback only */
- case PROC_WRITEBACK_MEM:
- dmac_clean_range(pMemBuf, pMemBuf + byte_size);
- outer_clean_range(__pa((u32) pMemBuf), __pa((u32) pMemBuf +
- byte_size));
- break;
- /* writeback and invalidate */
- case PROC_WRITEBACK_INVALIDATE_MEM:
- dmac_flush_range(pMemBuf, pMemBuf + byte_size);
- outer_flush_range(__pa((u32) pMemBuf), __pa((u32) pMemBuf +
- byte_size));
- break;
- }
-
-}
-
-/*
* ======== mem_free_phys_mem ========
* Purpose:
* Free the given block of physically contiguous memory.
>
> - kunmap(page);
> + sg_set_page(&sg[i], page, rest, offset);
> +
> len -= rest;
> start += rest;
> - pg_i++;
> + pg_i++, i++;
> + }
> +
> + if (i != map_info->dma_info.num_pages) {
> + pr_err("%s: bad number of sg iterations\n", __func__);
> + ret = -EFAULT;
> + goto out;
> + }
> +
> +out:
> + return ret;
> +}
> +
> +/* Cache operation against kernel address instead of users */
> +static int memory_release_ownership(struct memory_map_info *map_info,
> + unsigned long start, ssize_t len, enum dma_data_direction dir)
> +{
> + int pg_i, ret, sg_num;
> + struct scatterlist *sg;
> + unsigned long first_data_page = start >> PAGE_SHIFT;
> + unsigned long last_data_page = ((u32)(start + len - 1) >> PAGE_SHIFT);
> + /* calculating the number of pages this area spans */
> + unsigned long num_pages = last_data_page - first_data_page + 1;
> +
> + pg_i = find_first_page_in_cache(map_info, start);
> + if (pg_i < 0) {
> + pr_err("%s: failed to find first page in cache\n", __func__);
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + sg = kcalloc(num_pages, sizeof(*sg), GFP_KERNEL);
> + if (!sg) {
> + pr_err("%s: kcalloc failed\n", __func__);
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + sg_init_table(sg, num_pages);
> +
> + /* cleanup a previous sg allocation */
> + /* this may happen if application doesn't signal for e/o DMA */
> + kfree(map_info->dma_info.sg);
> +
> + map_info->dma_info.sg = sg;
> + map_info->dma_info.dir = dir;
> + map_info->dma_info.num_pages = num_pages;
> +
> + ret = build_dma_sg(map_info, start, len, pg_i);
> + if (ret)
> + goto kfree_sg;
> +
> + sg_num = dma_map_sg(bridge, sg, num_pages, dir);
> + if (sg_num < 1) {
> + pr_err("%s: dma_map_sg failed: %d\n", __func__, sg_num);
> + ret = -EFAULT;
> + goto kfree_sg;
> }
>
> + pr_debug("%s: dma_map_sg mapped %d elements\n", __func__, sg_num);
> + map_info->dma_info.sg_num = sg_num;
> +
> return 0;
> +
> +kfree_sg:
> + kfree(sg);
> + map_info->dma_info.sg = NULL;
> +out:
> + return ret;
> }
>
> -static dsp_status proc_memory_sync(void *hprocessor, void *pmpu_addr,
> - u32 ul_size, u32 ul_flags,
> - enum dsp_flushtype ftype)
> +static dsp_status proc_begin_dma(void *hprocessor, void *pmpu_addr,
> + u32 ul_size, u32 ul_flags,
> + enum dma_data_direction dir)
> {
> /* Keep STATUS here for future additions to this function */
> dsp_status status = DSP_SOK;
> @@ -684,7 +776,7 @@ static dsp_status proc_memory_sync(void *hprocessor, void *pmpu_addr,
>
> pr_debug("%s: addr 0x%x, size 0x%x, type %d\n", __func__,
> (u32)pmpu_addr,
> - ul_size, ftype);
> + ul_size, dir);
>
> /* find requested memory are in cached mapping information */
> map_info = find_containing_mapping(p_proc_object, (u32) pmpu_addr,
> @@ -695,7 +787,8 @@ static dsp_status proc_memory_sync(void *hprocessor, void *pmpu_addr,
> goto err_out;
> }
>
> - if (memory_sync_page(map_info, (u32) pmpu_addr, ul_size, ftype)) {
> + if (memory_release_ownership(map_info, (u32) pmpu_addr, ul_size,
> + dir)) {
> pr_err("%s: InValid address parameters %p %x\n",
> __func__, pmpu_addr, ul_size);
> status = DSP_EHANDLE;
> @@ -710,13 +803,12 @@ err_out:
> * Purpose:
> * Flush cache
> */
> -dsp_status proc_flush_memory(void *hprocessor, void *pmpu_addr,
> +dsp_status proc_begin_dma_to_dsp(void *hprocessor, void *pmpu_addr,
> u32 ul_size, u32 ul_flags)
> {
> - enum dsp_flushtype mtype = PROC_WRITEBACK_INVALIDATE_MEM;
> + enum dma_data_direction dir = DMA_BIDIRECTIONAL;
>
> - return proc_memory_sync(hprocessor, pmpu_addr, ul_size, ul_flags,
> - mtype);
> + return proc_begin_dma(hprocessor, pmpu_addr, ul_size, ul_flags, dir);
> }
>
> /*
> @@ -724,12 +816,12 @@ dsp_status proc_flush_memory(void *hprocessor, void *pmpu_addr,
> * Purpose:
> * Invalidates the memory specified
> */
> -dsp_status proc_invalidate_memory(void *hprocessor, void *pmpu_addr,
> +dsp_status proc_begin_dma_from_dsp(void *hprocessor, void *pmpu_addr,
> u32 ul_size)
> {
> - enum dsp_flushtype mtype = PROC_INVALIDATE_MEM;
> + enum dma_data_direction dir = DMA_FROM_DEVICE;
>
> - return proc_memory_sync(hprocessor, pmpu_addr, ul_size, 0, mtype);
> + return proc_begin_dma(hprocessor, pmpu_addr, ul_size, 0, dir);
> }
>
> /*
> --
> 1.6.3.3
>
>
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