Hi Laura,
Thanks for your thorough review! I will fix all the pointed issues once the main point of this patch set (using /chosen/contiguous-memory for CMA DT bindings) will be agreed and accepted.
On 4/11/2013 7:56 PM, Laura Abbott wrote:
Hi,
On 4/11/2013 4:22 AM, Marek Szyprowski wrote: ...
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 01fe743..6a8abab 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c @@ -24,6 +24,9 @@
#include <linux/memblock.h> #include <linux/err.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/of_platform.h> #include <linux/mm.h> #include <linux/mutex.h> #include <linux/page-isolation.h> @@ -37,6 +40,7 @@ struct cma { unsigned long base_pfn; unsigned long count; unsigned long *bitmap;
char full_name[32]; };
static DEFINE_MUTEX(cma_mutex);
@@ -133,6 +137,53 @@ static __init int cma_activate_area(struct cma *cma) return 0; }
+/*****************************************************************************/
+#ifdef CONFIG_OF +int __init cma_fdt_scan(unsigned long node, const char *uname,
int depth, void *data)+{
- static int level;
- phys_addr_t base, size;
- unsigned long len;
- struct cma *cma;
- __be32 *prop;
- if (depth == 1 && strcmp(uname, "chosen") == 0) {
level = depth;return 0;- }
- if (depth == 2 && strcmp(uname, "contiguous-memory") == 0) {
level = depth;return 0;- }
- if (level != 2 || depth != 3 || strncmp(uname, "region@", 7) != 0)
return 0;Requiring the region@ label does not work if you want two dynamically placed regions (i.e. two region@0). The devicetree will take the last region@0 entry and ignore all the other ones
Hmm. You are right, I need different solution here to get it working with autoconfigured base address.
- prop = of_get_flat_dt_prop(node, "reg", &len);
- if (!prop || (len != 2 * sizeof(unsigned long)))
return 0;- base = be32_to_cpu(prop[0]);
- size = be32_to_cpu(prop[1]);
- pr_info("Found %s, memory base %lx, size %ld MiB\n", uname,
(unsigned long)base, (unsigned long)size / SZ_1M);- dma_contiguous_reserve_area(size, base, 0, &cma);
Need to check the return of dma_contiguous_reserve_area, else there is an abort when trying to access cma->name on an error
- strcpy(cma->full_name, uname);
- if (of_get_flat_dt_prop(node, "linux,default-contiguous-region",
NULL)) {
dma_contiguous_default_area = cma;- }
- return 0;
+} +#endif
- /**
- dma_contiguous_reserve() - reserve area(s) for contiguous memory
handling
- @limit: End address of the reserved memory (optional, 0 for any).
if the contiguous region isn't set via devicetree, default_area->full_name needs to be set in dma_contiguous_reserve, else we get wrong associations in scan_cma_node.
@@ -149,6 +200,10 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit);+#ifdef CONFIG_OF
- of_scan_flat_dt(cma_fdt_scan, NULL);
+#endif
if (size_cmdline != -1) { sel_size = size_cmdline; } else {@@ -265,6 +320,71 @@ int __init dma_contiguous_add_device(struct device *dev, struct cma *cma) return 0; }
+#ifdef CONFIG_OF +static struct cma_map {
- struct cma *cma;
- struct device_node *node;
+} cma_maps[MAX_CMA_AREAS]; +static unsigned cma_map_count;
+static void cma_assign_device_from_dt(struct device *dev) +{
- int i;
- for (i=0; i<cma_map_count; i++) {
if (cma_maps[i].node == dev->of_node) {dev_set_cma_area(dev, cma_maps[i].cma);pr_info("Assigned CMA %s to %s device\n",cma_maps[i].cma->full_name,dev_name(dev));}- }
+}
+static int cma_device_init_notifier_call(struct notifier_block *nb,
unsigned long event, void *data)+{
- struct device *dev = data;
- if (event == BUS_NOTIFY_ADD_DEVICE && dev->of_node)
cma_assign_device_from_dt(dev);- return NOTIFY_DONE;
+}
+static struct notifier_block cma_dev_init_nb = {
- .notifier_call = cma_device_init_notifier_call,
+};
+void scan_cma_nodes(void) +{
- struct device_node *parent =
of_find_node_by_path("/chosen/contiguous-memory");
- struct device_node *child;
- if (!parent)
return;- for_each_child_of_node(parent, child) {
struct cma *cma = NULL;int i;for (i=0; i<cma_area_count; i++)if (strstr(child->full_name, cma_areas[i].full_name))cma = &cma_areas[i];break out of the loop once the area is found?
Also, how will the code deal with region names that are substrings of each other e.g.
region@1000000 region@10000000
Thanks for pointing this.
if (!cma)continue;for (i=0;; i++) {struct device_node *node;node = of_parse_phandle(child, "device", i);if (!node)break;cma_maps[cma_map_count].cma = cma;cma_maps[cma_map_count].node = node;cma_map_count++;Bounds check cma_map_count against MAX_CMA_AREAS?
}- }
+} +#endif
- static int __init cma_init_reserved_areas(void) { int i;
@@ -275,6 +395,10 @@ static int __init cma_init_reserved_areas(void) return ret; }
+#ifdef CONFIG_OF
- scan_cma_nodes();
- bus_register_notifier(&platform_bus_type, &cma_dev_init_nb);
+#endif return 0; } core_initcall(cma_init_reserved_areas);
Thanks, Laura
Best regards