acpi: Support ordering SSDT data by device

Add a /chosen property to control the order in which the data appears
in the SSDT. This allows matching up U-Boot's output from a dump of the
known-good data obtained from within Linux.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index 5b41edd8d3b2b59c2e3ee5aa5715de8505bc6fe7..c79ea349324319d22e322ce9648273e440c6febf 100644 (file)
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -254,7 +254,7 @@
                compatible = "denx,u-boot-devres-test";
        };
 
-       acpi-test {
+       acpi_test1: acpi-test {
                compatible = "denx,u-boot-acpi-test";
                acpi-ssdt-test-data = "ab";
                child {
@@ -262,7 +262,7 @@
                };
        };
 
-       acpi-test2 {
+       acpi_test2: acpi-test2 {
                compatible = "denx,u-boot-acpi-test";
                acpi-ssdt-test-data = "cd";
        };
@@ -924,6 +924,7 @@
                setting = "sunrise ohoka";
                other-node = "/some-bus/c-test@5";
                int-values = <0x1937 72993>;
+               u-boot,acpi-ssdt-order = <&acpi_test2 &acpi_test1>;
                chosen-test {
                        compatible = "denx,u-boot-fdt-test";
                        reg = <9 1>;

diff --git a/doc/device-tree-bindings/chosen.txt b/doc/device-tree-bindings/chosen.txt
index 395c9501e3bdafd01ffac650e7cab7b3c0f8c3f9..d4dfc05847b8ab9aafc45a8c2ed91c7d40b51a4e 100644 (file)
--- a/doc/device-tree-bindings/chosen.txt
+++ b/doc/device-tree-bindings/chosen.txt
@@ -134,3 +134,12 @@ Example
                phandlepart = <&mmc 1>;
        };
 };
+
+u-boot,acpi-ssdt-order
+----------------------
+
+This provides the ordering to use when writing device data to the ACPI SSDT
+(Secondary System Descriptor Table). Each cell is a phandle pointer to a device
+node to add. The ACPI information is written in this order.
+
+If the ordering does not include all nodes, an error is generated.

diff --git a/drivers/core/acpi.c b/drivers/core/acpi.c
index df3d7ba417dd6550a588356b68cbd08821c69ada..a9b7fc1d9a077156776b187b64c57f13ba55759a 100644 (file)
--- a/drivers/core/acpi.c
+++ b/drivers/core/acpi.c
@@ -108,6 +108,85 @@ static int acpi_add_item(struct acpi_ctx *ctx, struct udevice *dev,
        return 0;
 }
 
+static struct acpi_item *find_acpi_item(const char *devname)
+{
+       int i;
+
+       for (i = 0; i < item_count; i++) {
+               struct acpi_item *item = &acpi_item[i];
+
+               if (!strcmp(devname, item->dev->name))
+                       return item;
+       }
+
+       return NULL;
+}
+
+/**
+ * sort_acpi_item_type - Sort the ACPI items into the desired order
+ *
+ * This looks up the ordering in the device tree and then adds each item one by
+ * one into the supplied buffer
+ *
+ * @ctx: ACPI context
+ * @start: Start position to put the sorted items. The items will follow each
+ *     other in sorted order
+ * @type: Type of items to sort
+ * @return 0 if OK, -ve on error
+ */
+static int sort_acpi_item_type(struct acpi_ctx *ctx, void *start,
+                              enum gen_type_t type)
+{
+       const u32 *order;
+       int size;
+       int count;
+       void *ptr;
+       void *end = ctx->current;
+
+       ptr = start;
+       order = ofnode_read_chosen_prop("u-boot,acpi-ssdt-order", &size);
+       if (!order) {
+               log_warning("Failed to find ordering, leaving as is\n");
+               return 0;
+       }
+
+       /*
+        * This algorithm rewrites the context buffer without changing its
+        * length. So there is no need to update ctx-current
+        */
+       count = size / sizeof(u32);
+       while (count--) {
+               struct acpi_item *item;
+               const char *name;
+               ofnode node;
+
+               node = ofnode_get_by_phandle(fdt32_to_cpu(*order++));
+               name = ofnode_get_name(node);
+               item = find_acpi_item(name);
+               if (!item) {
+                       log_err("Failed to find item '%s'\n", name);
+                       return log_msg_ret("find", -ENOENT);
+               }
+               if (item->type == type) {
+                       log_debug("   - add %s\n", item->dev->name);
+                       memcpy(ptr, item->buf, item->size);
+                       ptr += item->size;
+               }
+       }
+
+       /*
+        * If the sort order is missing an item then the output will be too
+        * small. Report this error since the item needs to be added to the
+        * ordering for the ACPI tables to be complete.
+        */
+       if (ptr != end) {
+               log_warning("*** Missing bytes: ptr=%p, end=%p\n", ptr, end);
+               return -ENXIO;
+       }
+
+       return 0;
+}
+
 acpi_method acpi_get_method(struct udevice *dev, enum method_t method)
 {
        struct acpi_ops *aops;
@@ -163,11 +242,16 @@ int acpi_recurse_method(struct acpi_ctx *ctx, struct udevice *parent,
 
 int acpi_fill_ssdt(struct acpi_ctx *ctx)
 {
+       void *start = ctx->current;
        int ret;
 
        log_debug("Writing SSDT tables\n");
+       item_count = 0;
        ret = acpi_recurse_method(ctx, dm_root(), METHOD_FILL_SSDT, TYPE_SSDT);
        log_debug("Writing SSDT finished, err=%d\n", ret);
+       ret = sort_acpi_item_type(ctx, start, TYPE_SSDT);
+       if (ret)
+               return log_msg_ret("build", ret);
 
        return ret;
 }

diff --git a/test/dm/acpi.c b/test/dm/acpi.c
index d46d1fbe66f9698b1e86e045d33a8fb5b82fd029..4e1d401e0d6c48f7f8eab9dcb6e4b9189d116ce3 100644 (file)
--- a/test/dm/acpi.c
+++ b/test/dm/acpi.c
@@ -425,13 +425,16 @@ static int dm_test_acpi_fill_ssdt(struct unit_test_state *uts)
        buf[4] = 'z';   /* sentinel */
        ut_assertok(acpi_fill_ssdt(&ctx));
 
-       /* These values come from acpi-test's acpi-ssdt-test-data property */
-       ut_asserteq('a', buf[0]);
-       ut_asserteq('b', buf[1]);
+       /*
+        * These values come from acpi-test2's acpi-ssdt-test-data property.
+        * This device comes first because of u-boot,acpi-ssdt-order
+        */
+       ut_asserteq('c', buf[0]);
+       ut_asserteq('d', buf[1]);
 
-       /* These values come from acpi-test2's acpi-ssdt-test-data property */
-       ut_asserteq('c', buf[2]);
-       ut_asserteq('d', buf[3]);
+       /* These values come from acpi-test's acpi-ssdt-test-data property */
+       ut_asserteq('a', buf[2]);
+       ut_asserteq('b', buf[3]);
 
        ut_asserteq('z', buf[4]);