acpi: Support generation of a generic register

Allow writing out a generic register.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
[bmeng: Fix build failures on Sandbox]
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

diff --git a/include/acpi/acpi_device.h b/include/acpi/acpi_device.h
index 5d94a88c02da80ae2abb72202af77496a9151566..11461e168d38413ab3df2be0160839c16ab5ae7b 100644 (file)
--- a/include/acpi/acpi_device.h
+++ b/include/acpi/acpi_device.h
@@ -20,6 +20,7 @@ struct udevice;
 
 /* ACPI descriptor values for common descriptors: SERIAL_BUS means I2C */
 #define ACPI_DESCRIPTOR_LARGE          BIT(7)
+#define ACPI_DESCRIPTOR_REGISTER       (ACPI_DESCRIPTOR_LARGE | 2)
 #define ACPI_DESCRIPTOR_INTERRUPT      (ACPI_DESCRIPTOR_LARGE | 9)
 #define ACPI_DESCRIPTOR_GPIO           (ACPI_DESCRIPTOR_LARGE | 12)
 #define ACPI_DESCRIPTOR_SERIAL_BUS     (ACPI_DESCRIPTOR_LARGE | 14)

diff --git a/include/acpi/acpigen.h b/include/acpi/acpigen.h
index 4a606125de0aa483311a949bc7baf292566d7466..1f37c9c31cdfaa5cb32c3ed611ababa0b858e618 100644 (file)
--- a/include/acpi/acpigen.h
+++ b/include/acpi/acpigen.h
@@ -13,6 +13,7 @@
 #include <linux/types.h>
 
 struct acpi_ctx;
+struct acpi_gen_regaddr;
 struct acpi_gpio;
 
 /* Top 4 bits of the value used to indicate a three-byte length value */
@@ -21,6 +22,8 @@ struct acpi_gpio;
 #define ACPI_METHOD_NARGS_MASK         0x7
 #define ACPI_METHOD_SERIALIZED_MASK    BIT(3)
 
+#define ACPI_END_TAG                   0x79
+
 /* ACPI Op/Prefix codes */
 enum {
        ZERO_OP                 = 0x00,
@@ -318,6 +321,31 @@ void acpigen_write_method_serialized(struct acpi_ctx *ctx, const char *name,
  */
 void acpigen_write_sta(struct acpi_ctx *ctx, uint status);
 
+/**
+ * acpigen_write_resourcetemplate_header() - Write a ResourceTemplate header
+ *
+ * @ctx: ACPI context pointer
+ */
+void acpigen_write_resourcetemplate_header(struct acpi_ctx *ctx);
+
+/**
+ * acpigen_write_resourcetemplate_footer() - Write a ResourceTemplate footer
+ *
+ * @ctx: ACPI context pointer
+ */
+void acpigen_write_resourcetemplate_footer(struct acpi_ctx *ctx);
+
+/**
+ * acpigen_write_register_resource() - Write a register resource
+ *
+ * This writes a header, the address information and a footer
+ *
+ * @ctx: ACPI context pointer
+ * @addr: Address to write
+ */
+void acpigen_write_register_resource(struct acpi_ctx *ctx,
+                                    const struct acpi_gen_regaddr *addr);
+
 /**
  * acpigen_write_sleep() - Write a sleep operation
  *

diff --git a/lib/acpi/acpigen.c b/lib/acpi/acpigen.c
index 1e0a489d7b93ed9960bcaba2efb37283babbcb51..45691b79610ae4d00daf8d83a13193edbceaa225 100644 (file)
--- a/lib/acpi/acpigen.c
+++ b/lib/acpi/acpigen.c
@@ -14,6 +14,7 @@
 #include <uuid.h>
 #include <acpi/acpigen.h>
 #include <acpi/acpi_device.h>
+#include <acpi/acpi_table.h>
 #include <dm/acpi.h>
 
 u8 *acpigen_get_current(struct acpi_ctx *ctx)
@@ -299,6 +300,76 @@ void acpigen_write_sta(struct acpi_ctx *ctx, uint status)
        acpigen_pop_len(ctx);
 }
 
+static void acpigen_write_register(struct acpi_ctx *ctx,
+                                  const struct acpi_gen_regaddr *addr)
+{
+       /* See ACPI v6.3 section 6.4.3.7: Generic Register Descriptor */
+       acpigen_emit_byte(ctx, ACPI_DESCRIPTOR_REGISTER);
+       acpigen_emit_byte(ctx, 0x0c);           /* Register Length 7:0 */
+       acpigen_emit_byte(ctx, 0x00);           /* Register Length 15:8 */
+       acpigen_emit_byte(ctx, addr->space_id);
+       acpigen_emit_byte(ctx, addr->bit_width);
+       acpigen_emit_byte(ctx, addr->bit_offset);
+       acpigen_emit_byte(ctx, addr->access_size);
+       acpigen_emit_dword(ctx, addr->addrl);
+       acpigen_emit_dword(ctx, addr->addrh);
+}
+
+void acpigen_write_resourcetemplate_header(struct acpi_ctx *ctx)
+{
+       /*
+        * A ResourceTemplate() is a Buffer() with a
+        * (Byte|Word|DWord) containing the length, followed by one or more
+        * resource items, terminated by the end tag.
+        * (small item 0xf, len 1)
+        */
+       acpigen_emit_byte(ctx, BUFFER_OP);
+       acpigen_write_len_f(ctx);
+       acpigen_emit_byte(ctx, WORD_PREFIX);
+       ctx->len_stack[ctx->ltop++] = ctx->current;
+
+       /*
+        * Add two dummy bytes for the ACPI word (keep aligned with the
+        * calculation in acpigen_write_resourcetemplate_footer() below)
+        */
+       acpigen_emit_byte(ctx, 0x00);
+       acpigen_emit_byte(ctx, 0x00);
+}
+
+void acpigen_write_resourcetemplate_footer(struct acpi_ctx *ctx)
+{
+       char *p = ctx->len_stack[--ctx->ltop];
+       int len;
+       /*
+        * See ACPI v6.3 section 6.4.2.9: End Tag
+        * 0x79 <checksum>
+        * 0x00 is treated as a good checksum according to the spec
+        * and is what iasl generates.
+        */
+       acpigen_emit_byte(ctx, ACPI_END_TAG);
+       acpigen_emit_byte(ctx, 0x00);
+
+       /*
+        * Start counting past the 2-bytes length added in
+        * acpigen_write_resourcetemplate_header() above
+        */
+       len = (char *)ctx->current - (p + 2);
+
+       /* patch len word */
+       p[0] = len & 0xff;
+       p[1] = (len >> 8) & 0xff;
+
+       acpigen_pop_len(ctx);
+}
+
+void acpigen_write_register_resource(struct acpi_ctx *ctx,
+                                    const struct acpi_gen_regaddr *addr)
+{
+       acpigen_write_resourcetemplate_header(ctx);
+       acpigen_write_register(ctx, addr);
+       acpigen_write_resourcetemplate_footer(ctx);
+}
+
 /*
  * ToUUID(uuid)
  *

diff --git a/test/dm/acpigen.c b/test/dm/acpigen.c
index 46792d8e89fe1f25c36bd78fc6d98d7a530c6b75..822641afb01220a9a9c708eede08a13f88650401 100644 (file)
--- a/test/dm/acpigen.c
+++ b/test/dm/acpigen.c
@@ -12,6 +12,7 @@
 #include <malloc.h>
 #include <acpi/acpigen.h>
 #include <acpi/acpi_device.h>
+#include <acpi/acpi_table.h>
 #include <asm/gpio.h>
 #include <asm/unaligned.h>
 #include <dm/acpi.h>
@@ -947,3 +948,48 @@ static int dm_test_acpi_scope(struct unit_test_state *uts)
        return 0;
 }
 DM_TEST(dm_test_acpi_scope, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/* Test writing a resource template */
+static int dm_test_acpi_resource_template(struct unit_test_state *uts)
+{
+       struct acpi_gen_regaddr addr;
+       struct acpi_ctx *ctx;
+       u8 *ptr;
+
+       ut_assertok(alloc_context(&ctx));
+       ptr = acpigen_get_current(ctx);
+
+       addr.space_id = ACPI_ADDRESS_SPACE_EC;
+       addr.bit_width = 32;
+       addr.bit_offset = 8;
+       addr.access_size = ACPI_ACCESS_SIZE_DWORD_ACCESS;
+       addr.addrl = TEST_INT64 & 0xffffffff;
+       addr.addrh = TEST_INT64 >> 32;
+       acpigen_write_register_resource(ctx, &addr);
+
+       ut_asserteq(BUFFER_OP, *ptr++);
+       ut_asserteq(0x17, acpi_test_get_length(ptr));
+       ptr += 3;
+       ut_asserteq(WORD_PREFIX, *ptr++);
+       ut_asserteq(0x11, get_unaligned((u16 *)ptr));
+       ptr += 2;
+       ut_asserteq(ACPI_DESCRIPTOR_REGISTER, *ptr++);
+       ut_asserteq(0xc, *ptr++);
+       ut_asserteq(0, *ptr++);
+       ut_asserteq(ACPI_ADDRESS_SPACE_EC, *ptr++);
+       ut_asserteq(32, *ptr++);
+       ut_asserteq(8, *ptr++);
+       ut_asserteq(ACPI_ACCESS_SIZE_DWORD_ACCESS, *ptr++);
+       ut_asserteq(TEST_INT64 & 0xffffffff, get_unaligned((u32 *)ptr));
+       ptr += 4;
+       ut_asserteq(TEST_INT64 >> 32, get_unaligned((u32 *)ptr));
+       ptr += 4;
+       ut_asserteq(ACPI_END_TAG, *ptr++);
+       ut_asserteq(0x00, *ptr++);
+       ut_asserteq_ptr(ptr, ctx->current);
+
+       free_context(&ctx);
+
+       return 0;
+}
+DM_TEST(dm_test_acpi_resource_template, 0);