[PATCH v4 29/35] acpi: Support ordering SSDT data by device
Simon Glass
sjg at chromium.org
Tue Jul 7 21:12:06 CEST 2020
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 at chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com>
---
Changes in v4:
- Explain in sort_acpi_item_type() why ctx->current is not updated
Changes in v3:
- Make find_item() static and rename to find_acpi_item()
- Rename build_type() and add a comment
Changes in v1:
- Generalise the ACPI function recursion with acpi_recurse_method()
arch/sandbox/dts/test.dts | 5 +-
doc/device-tree-bindings/chosen.txt | 9 ++++
drivers/core/acpi.c | 84 +++++++++++++++++++++++++++++
test/dm/acpi.c | 15 +++---
4 files changed, 105 insertions(+), 8 deletions(-)
diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index ea686f0cb3..6687efe2ae 100644
--- 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";
};
@@ -904,6 +904,7 @@
setting = "sunrise ohoka";
other-node = "/some-bus/c-test at 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 395c9501e3..d4dfc05847 100644
--- 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 df3d7ba417..a9b7fc1d9a 100644
--- 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 d46d1fbe66..4e1d401e0d 100644
--- 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]);
--
2.27.0.383.g050319c2ae-goog
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