diff mbox series

[v4,31/35] acpi: Add support for DSDT generation

Message ID 20200707191212.2542638-18-sjg@chromium.org
State Accepted
Commit 01694589af589212d6f2a6241821896ef9e334d3
Headers show
Series dm: Add programmatic generation of ACPI tables (part B) | expand

Commit Message

Simon Glass July 7, 2020, 7:12 p.m. UTC
Some devices need to inject extra code into the Differentiated System
Descriptor Table (DSDT). Add a method to handle this.

Signed-off-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com>
---

Changes in v4:
- Explain why 'fill' is used for one method and 'inject' for another

Changes in v3:
- Fix 'THe' typo
- Rename build_type() to sort_acpi_item_type()

Changes in v1:
- Generalise the ACPI function recursion with acpi_recurse_method()

 arch/sandbox/dts/test.dts |  2 ++
 drivers/core/acpi.c       | 25 +++++++++++++++++++++-
 include/dm/acpi.h         | 30 ++++++++++++++++++++++++++
 test/dm/acpi.c            | 44 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 100 insertions(+), 1 deletion(-)

Comments

Bin Meng July 13, 2020, 3:17 a.m. UTC | #1
On Wed, Jul 8, 2020 at 3:13 AM Simon Glass <sjg at chromium.org> wrote:
>
> Some devices need to inject extra code into the Differentiated System
> Descriptor Table (DSDT). Add a method to handle this.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com>
> ---
>
> Changes in v4:
> - Explain why 'fill' is used for one method and 'inject' for another
>
> Changes in v3:
> - Fix 'THe' typo
> - Rename build_type() to sort_acpi_item_type()
>
> Changes in v1:
> - Generalise the ACPI function recursion with acpi_recurse_method()
>
>  arch/sandbox/dts/test.dts |  2 ++
>  drivers/core/acpi.c       | 25 +++++++++++++++++++++-
>  include/dm/acpi.h         | 30 ++++++++++++++++++++++++++
>  test/dm/acpi.c            | 44 +++++++++++++++++++++++++++++++++++++++
>  4 files changed, 100 insertions(+), 1 deletion(-)
>
> diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
> index 6687efe2ae..fc6a6b1774 100644
> --- a/arch/sandbox/dts/test.dts
> +++ b/arch/sandbox/dts/test.dts
> @@ -257,6 +257,7 @@
>         acpi_test1: acpi-test {
>                 compatible = "denx,u-boot-acpi-test";
>                 acpi-ssdt-test-data = "ab";
> +               acpi-dsdt-test-data = "hi";
>                 child {
>                         compatible = "denx,u-boot-acpi-test";
>                 };
> @@ -265,6 +266,7 @@
>         acpi_test2: acpi-test2 {
>                 compatible = "denx,u-boot-acpi-test";
>                 acpi-ssdt-test-data = "cd";
> +               acpi-dsdt-test-data = "jk";
>         };
>
>         clocks {
> diff --git a/drivers/core/acpi.c b/drivers/core/acpi.c
> index a9b7fc1d9a..7b32694ad4 100644
> --- a/drivers/core/acpi.c
> +++ b/drivers/core/acpi.c
> @@ -22,12 +22,14 @@
>  enum gen_type_t {
>         TYPE_NONE,
>         TYPE_SSDT,
> +       TYPE_DSDT,
>  };
>
>  /* Type of method to call */
>  enum method_t {
>         METHOD_WRITE_TABLES,
>         METHOD_FILL_SSDT,
> +       METHOD_INJECT_DSDT,
>  };
>
>  /* Prototype for all methods */
> @@ -144,7 +146,9 @@ static int sort_acpi_item_type(struct acpi_ctx *ctx, void *start,
>         void *end = ctx->current;
>
>         ptr = start;
> -       order = ofnode_read_chosen_prop("u-boot,acpi-ssdt-order", &size);
> +       order = ofnode_read_chosen_prop(type == TYPE_DSDT ?
> +                                       "u-boot,acpi-dsdt-order" :
> +                                       "u-boot,acpi-ssdt-order", &size);
>         if (!order) {
>                 log_warning("Failed to find ordering, leaving as is\n");
>                 return 0;
> @@ -198,6 +202,8 @@ acpi_method acpi_get_method(struct udevice *dev, enum method_t method)
>                         return aops->write_tables;
>                 case METHOD_FILL_SSDT:
>                         return aops->fill_ssdt;
> +               case METHOD_INJECT_DSDT:
> +                       return aops->inject_dsdt;
>                 }
>         }
>
> @@ -256,6 +262,23 @@ int acpi_fill_ssdt(struct acpi_ctx *ctx)
>         return ret;
>  }
>
> +int acpi_inject_dsdt(struct acpi_ctx *ctx)
> +{
> +       void *start = ctx->current;
> +       int ret;
> +
> +       log_debug("Writing DSDT tables\n");
> +       item_count = 0;
> +       ret = acpi_recurse_method(ctx, dm_root(), METHOD_INJECT_DSDT,
> +                                 TYPE_DSDT);
> +       log_debug("Writing DSDT finished, err=%d\n", ret);
> +       ret = sort_acpi_item_type(ctx, start, TYPE_DSDT);
> +       if (ret)
> +               return log_msg_ret("build", ret);
> +
> +       return ret;
> +}
> +
>  int acpi_write_dev_tables(struct acpi_ctx *ctx)
>  {
>         int ret;
> diff --git a/include/dm/acpi.h b/include/dm/acpi.h
> index e956e49680..72fa71d0a2 100644
> --- a/include/dm/acpi.h
> +++ b/include/dm/acpi.h
> @@ -82,11 +82,31 @@ struct acpi_ops {
>          * whatever ACPI code is needed by this device. It will end up in the
>          * SSDT table.
>          *
> +        * Note that this is called 'fill' because the entire contents of the
> +        * SSDT is build by calling this method on all devices.
> +        *
>          * @dev: Device to write
>          * @ctx: ACPI context to use
>          * @return 0 if OK, -ve on error
>          */
>         int (*fill_ssdt)(const struct udevice *dev, struct acpi_ctx *ctx);
> +
> +       /**
> +        * inject_dsdt() - Generate DSDT code for a device
> +        *
> +        * This is called to create the DSDT code. The method should write out
> +        * whatever ACPI code is needed by this device. It will end up in the
> +        * DSDT table.
> +        *
> +        * Note that this is called 'inject' because the output of calling this
> +        * method on all devices is injected into the DSDT, the bulk of which
> +        * is writte in .asl files for the board.

is wirtten

> +        *
> +        * @dev: Device to write
> +        * @ctx: ACPI context to use
> +        * @return 0 if OK, -ve on error
> +        */
> +       int (*inject_dsdt)(const struct udevice *dev, struct acpi_ctx *ctx);
>  };
>
>  #define device_get_acpi_ops(dev)       ((dev)->driver->acpi_ops)
> @@ -141,6 +161,16 @@ int acpi_write_dev_tables(struct acpi_ctx *ctx);
>   */
>  int acpi_fill_ssdt(struct acpi_ctx *ctx);
>
> +/**
> + * acpi_inject_dsdt() - Generate ACPI tables for DSDT
> + *
> + * This is called to create the DSDT code for all devices.
> + *
> + * @ctx: ACPI context to use
> + * @return 0 if OK, -ve on error
> + */
> +int acpi_inject_dsdt(struct acpi_ctx *ctx);
> +
>  #endif /* __ACPI__ */
>
>  #endif
> diff --git a/test/dm/acpi.c b/test/dm/acpi.c
> index 4e1d401e0d..1abde65c8c 100644
> --- a/test/dm/acpi.c
> +++ b/test/dm/acpi.c
> @@ -81,10 +81,24 @@ static int testacpi_fill_ssdt(const struct udevice *dev, struct acpi_ctx *ctx)
>         return 0;
>  }
>
> +static int testacpi_inject_dsdt(const struct udevice *dev, struct acpi_ctx *ctx)
> +{
> +       const char *data;
> +
> +       data = dev_read_string(dev, "acpi-dsdt-test-data");
> +       if (data) {
> +               while (*data)
> +                       acpigen_emit_byte(ctx, *data++);
> +       }
> +
> +       return 0;
> +}
> +
>  struct acpi_ops testacpi_ops = {
>         .get_name       = testacpi_get_name,
>         .write_tables   = testacpi_write_tables,
>         .fill_ssdt      = testacpi_fill_ssdt,
> +       .inject_dsdt    = testacpi_inject_dsdt,
>  };
>
>  static const struct udevice_id testacpi_ids[] = {
> @@ -441,3 +455,33 @@ static int dm_test_acpi_fill_ssdt(struct unit_test_state *uts)
>         return 0;
>  }
>  DM_TEST(dm_test_acpi_fill_ssdt, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
> +
> +/* Test acpi_inject_dsdt() */
> +static int dm_test_acpi_inject_dsdt(struct unit_test_state *uts)
> +{
> +       struct acpi_ctx ctx;
> +       u8 *buf;
> +
> +       buf = malloc(BUF_SIZE);
> +       ut_assertnonnull(buf);
> +
> +       ctx.current = buf;
> +       buf[4] = 'z';   /* sentinel */
> +       ut_assertok(acpi_inject_dsdt(&ctx));
> +
> +       /*
> +        * These values come from acpi-test's acpi-dsdt-test-data property.
> +        * There is no u-boot,acpi-dsdt-order so device-tree order is used.
> +        */
> +       ut_asserteq('h', buf[0]);
> +       ut_asserteq('i', buf[1]);
> +
> +       /* These values come from acpi-test's acpi-dsdt-test-data property */
> +       ut_asserteq('j', buf[2]);
> +       ut_asserteq('k', buf[3]);
> +
> +       ut_asserteq('z', buf[4]);
> +
> +       return 0;
> +}
> +DM_TEST(dm_test_acpi_inject_dsdt, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
> --

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
Bin Meng July 13, 2020, 4:22 a.m. UTC | #2
On Mon, Jul 13, 2020 at 11:17 AM Bin Meng <bmeng.cn at gmail.com> wrote:
>
> On Wed, Jul 8, 2020 at 3:13 AM Simon Glass <sjg at chromium.org> wrote:
> >
> > Some devices need to inject extra code into the Differentiated System
> > Descriptor Table (DSDT). Add a method to handle this.
> >
> > Signed-off-by: Simon Glass <sjg at chromium.org>
> > Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com>
> > ---
> >
> > Changes in v4:
> > - Explain why 'fill' is used for one method and 'inject' for another
> >
> > Changes in v3:
> > - Fix 'THe' typo
> > - Rename build_type() to sort_acpi_item_type()
> >
> > Changes in v1:
> > - Generalise the ACPI function recursion with acpi_recurse_method()
> >
> >  arch/sandbox/dts/test.dts |  2 ++
> >  drivers/core/acpi.c       | 25 +++++++++++++++++++++-
> >  include/dm/acpi.h         | 30 ++++++++++++++++++++++++++
> >  test/dm/acpi.c            | 44 +++++++++++++++++++++++++++++++++++++++
> >  4 files changed, 100 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
> > index 6687efe2ae..fc6a6b1774 100644
> > --- a/arch/sandbox/dts/test.dts
> > +++ b/arch/sandbox/dts/test.dts
> > @@ -257,6 +257,7 @@
> >         acpi_test1: acpi-test {
> >                 compatible = "denx,u-boot-acpi-test";
> >                 acpi-ssdt-test-data = "ab";
> > +               acpi-dsdt-test-data = "hi";
> >                 child {
> >                         compatible = "denx,u-boot-acpi-test";
> >                 };
> > @@ -265,6 +266,7 @@
> >         acpi_test2: acpi-test2 {
> >                 compatible = "denx,u-boot-acpi-test";
> >                 acpi-ssdt-test-data = "cd";
> > +               acpi-dsdt-test-data = "jk";
> >         };
> >
> >         clocks {
> > diff --git a/drivers/core/acpi.c b/drivers/core/acpi.c
> > index a9b7fc1d9a..7b32694ad4 100644
> > --- a/drivers/core/acpi.c
> > +++ b/drivers/core/acpi.c
> > @@ -22,12 +22,14 @@
> >  enum gen_type_t {
> >         TYPE_NONE,
> >         TYPE_SSDT,
> > +       TYPE_DSDT,
> >  };
> >
> >  /* Type of method to call */
> >  enum method_t {
> >         METHOD_WRITE_TABLES,
> >         METHOD_FILL_SSDT,
> > +       METHOD_INJECT_DSDT,
> >  };
> >
> >  /* Prototype for all methods */
> > @@ -144,7 +146,9 @@ static int sort_acpi_item_type(struct acpi_ctx *ctx, void *start,
> >         void *end = ctx->current;
> >
> >         ptr = start;
> > -       order = ofnode_read_chosen_prop("u-boot,acpi-ssdt-order", &size);
> > +       order = ofnode_read_chosen_prop(type == TYPE_DSDT ?
> > +                                       "u-boot,acpi-dsdt-order" :
> > +                                       "u-boot,acpi-ssdt-order", &size);
> >         if (!order) {
> >                 log_warning("Failed to find ordering, leaving as is\n");
> >                 return 0;
> > @@ -198,6 +202,8 @@ acpi_method acpi_get_method(struct udevice *dev, enum method_t method)
> >                         return aops->write_tables;
> >                 case METHOD_FILL_SSDT:
> >                         return aops->fill_ssdt;
> > +               case METHOD_INJECT_DSDT:
> > +                       return aops->inject_dsdt;
> >                 }
> >         }
> >
> > @@ -256,6 +262,23 @@ int acpi_fill_ssdt(struct acpi_ctx *ctx)
> >         return ret;
> >  }
> >
> > +int acpi_inject_dsdt(struct acpi_ctx *ctx)
> > +{
> > +       void *start = ctx->current;
> > +       int ret;
> > +
> > +       log_debug("Writing DSDT tables\n");
> > +       item_count = 0;
> > +       ret = acpi_recurse_method(ctx, dm_root(), METHOD_INJECT_DSDT,
> > +                                 TYPE_DSDT);
> > +       log_debug("Writing DSDT finished, err=%d\n", ret);
> > +       ret = sort_acpi_item_type(ctx, start, TYPE_DSDT);
> > +       if (ret)
> > +               return log_msg_ret("build", ret);
> > +
> > +       return ret;
> > +}
> > +
> >  int acpi_write_dev_tables(struct acpi_ctx *ctx)
> >  {
> >         int ret;
> > diff --git a/include/dm/acpi.h b/include/dm/acpi.h
> > index e956e49680..72fa71d0a2 100644
> > --- a/include/dm/acpi.h
> > +++ b/include/dm/acpi.h
> > @@ -82,11 +82,31 @@ struct acpi_ops {
> >          * whatever ACPI code is needed by this device. It will end up in the
> >          * SSDT table.
> >          *
> > +        * Note that this is called 'fill' because the entire contents of the
> > +        * SSDT is build by calling this method on all devices.
> > +        *
> >          * @dev: Device to write
> >          * @ctx: ACPI context to use
> >          * @return 0 if OK, -ve on error
> >          */
> >         int (*fill_ssdt)(const struct udevice *dev, struct acpi_ctx *ctx);
> > +
> > +       /**
> > +        * inject_dsdt() - Generate DSDT code for a device
> > +        *
> > +        * This is called to create the DSDT code. The method should write out
> > +        * whatever ACPI code is needed by this device. It will end up in the
> > +        * DSDT table.
> > +        *
> > +        * Note that this is called 'inject' because the output of calling this
> > +        * method on all devices is injected into the DSDT, the bulk of which
> > +        * is writte in .asl files for the board.
>
> is wirtten

Fixed this when applying

>
> > +        *
> > +        * @dev: Device to write
> > +        * @ctx: ACPI context to use
> > +        * @return 0 if OK, -ve on error
> > +        */
> > +       int (*inject_dsdt)(const struct udevice *dev, struct acpi_ctx *ctx);
> >  };
> >
> >  #define device_get_acpi_ops(dev)       ((dev)->driver->acpi_ops)
> > @@ -141,6 +161,16 @@ int acpi_write_dev_tables(struct acpi_ctx *ctx);
> >   */
> >  int acpi_fill_ssdt(struct acpi_ctx *ctx);
> >
> > +/**
> > + * acpi_inject_dsdt() - Generate ACPI tables for DSDT
> > + *
> > + * This is called to create the DSDT code for all devices.
> > + *
> > + * @ctx: ACPI context to use
> > + * @return 0 if OK, -ve on error
> > + */
> > +int acpi_inject_dsdt(struct acpi_ctx *ctx);
> > +
> >  #endif /* __ACPI__ */
> >
> >  #endif
> > diff --git a/test/dm/acpi.c b/test/dm/acpi.c
> > index 4e1d401e0d..1abde65c8c 100644
> > --- a/test/dm/acpi.c
> > +++ b/test/dm/acpi.c
> > @@ -81,10 +81,24 @@ static int testacpi_fill_ssdt(const struct udevice *dev, struct acpi_ctx *ctx)
> >         return 0;
> >  }
> >
> > +static int testacpi_inject_dsdt(const struct udevice *dev, struct acpi_ctx *ctx)
> > +{
> > +       const char *data;
> > +
> > +       data = dev_read_string(dev, "acpi-dsdt-test-data");
> > +       if (data) {
> > +               while (*data)
> > +                       acpigen_emit_byte(ctx, *data++);
> > +       }
> > +
> > +       return 0;
> > +}
> > +
> >  struct acpi_ops testacpi_ops = {
> >         .get_name       = testacpi_get_name,
> >         .write_tables   = testacpi_write_tables,
> >         .fill_ssdt      = testacpi_fill_ssdt,
> > +       .inject_dsdt    = testacpi_inject_dsdt,
> >  };
> >
> >  static const struct udevice_id testacpi_ids[] = {
> > @@ -441,3 +455,33 @@ static int dm_test_acpi_fill_ssdt(struct unit_test_state *uts)
> >         return 0;
> >  }
> >  DM_TEST(dm_test_acpi_fill_ssdt, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
> > +
> > +/* Test acpi_inject_dsdt() */
> > +static int dm_test_acpi_inject_dsdt(struct unit_test_state *uts)
> > +{
> > +       struct acpi_ctx ctx;
> > +       u8 *buf;
> > +
> > +       buf = malloc(BUF_SIZE);
> > +       ut_assertnonnull(buf);
> > +
> > +       ctx.current = buf;
> > +       buf[4] = 'z';   /* sentinel */
> > +       ut_assertok(acpi_inject_dsdt(&ctx));
> > +
> > +       /*
> > +        * These values come from acpi-test's acpi-dsdt-test-data property.
> > +        * There is no u-boot,acpi-dsdt-order so device-tree order is used.
> > +        */
> > +       ut_asserteq('h', buf[0]);
> > +       ut_asserteq('i', buf[1]);
> > +
> > +       /* These values come from acpi-test's acpi-dsdt-test-data property */
> > +       ut_asserteq('j', buf[2]);
> > +       ut_asserteq('k', buf[3]);
> > +
> > +       ut_asserteq('z', buf[4]);
> > +
> > +       return 0;
> > +}
> > +DM_TEST(dm_test_acpi_inject_dsdt, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
> > --
>
> Reviewed-by: Bin Meng <bmeng.cn at gmail.com>

applied to u-boot-x86, thanks!
diff mbox series

Patch

diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index 6687efe2ae..fc6a6b1774 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -257,6 +257,7 @@ 
 	acpi_test1: acpi-test {
 		compatible = "denx,u-boot-acpi-test";
 		acpi-ssdt-test-data = "ab";
+		acpi-dsdt-test-data = "hi";
 		child {
 			compatible = "denx,u-boot-acpi-test";
 		};
@@ -265,6 +266,7 @@ 
 	acpi_test2: acpi-test2 {
 		compatible = "denx,u-boot-acpi-test";
 		acpi-ssdt-test-data = "cd";
+		acpi-dsdt-test-data = "jk";
 	};
 
 	clocks {
diff --git a/drivers/core/acpi.c b/drivers/core/acpi.c
index a9b7fc1d9a..7b32694ad4 100644
--- a/drivers/core/acpi.c
+++ b/drivers/core/acpi.c
@@ -22,12 +22,14 @@ 
 enum gen_type_t {
 	TYPE_NONE,
 	TYPE_SSDT,
+	TYPE_DSDT,
 };
 
 /* Type of method to call */
 enum method_t {
 	METHOD_WRITE_TABLES,
 	METHOD_FILL_SSDT,
+	METHOD_INJECT_DSDT,
 };
 
 /* Prototype for all methods */
@@ -144,7 +146,9 @@  static int sort_acpi_item_type(struct acpi_ctx *ctx, void *start,
 	void *end = ctx->current;
 
 	ptr = start;
-	order = ofnode_read_chosen_prop("u-boot,acpi-ssdt-order", &size);
+	order = ofnode_read_chosen_prop(type == TYPE_DSDT ?
+					"u-boot,acpi-dsdt-order" :
+					"u-boot,acpi-ssdt-order", &size);
 	if (!order) {
 		log_warning("Failed to find ordering, leaving as is\n");
 		return 0;
@@ -198,6 +202,8 @@  acpi_method acpi_get_method(struct udevice *dev, enum method_t method)
 			return aops->write_tables;
 		case METHOD_FILL_SSDT:
 			return aops->fill_ssdt;
+		case METHOD_INJECT_DSDT:
+			return aops->inject_dsdt;
 		}
 	}
 
@@ -256,6 +262,23 @@  int acpi_fill_ssdt(struct acpi_ctx *ctx)
 	return ret;
 }
 
+int acpi_inject_dsdt(struct acpi_ctx *ctx)
+{
+	void *start = ctx->current;
+	int ret;
+
+	log_debug("Writing DSDT tables\n");
+	item_count = 0;
+	ret = acpi_recurse_method(ctx, dm_root(), METHOD_INJECT_DSDT,
+				  TYPE_DSDT);
+	log_debug("Writing DSDT finished, err=%d\n", ret);
+	ret = sort_acpi_item_type(ctx, start, TYPE_DSDT);
+	if (ret)
+		return log_msg_ret("build", ret);
+
+	return ret;
+}
+
 int acpi_write_dev_tables(struct acpi_ctx *ctx)
 {
 	int ret;
diff --git a/include/dm/acpi.h b/include/dm/acpi.h
index e956e49680..72fa71d0a2 100644
--- a/include/dm/acpi.h
+++ b/include/dm/acpi.h
@@ -82,11 +82,31 @@  struct acpi_ops {
 	 * whatever ACPI code is needed by this device. It will end up in the
 	 * SSDT table.
 	 *
+	 * Note that this is called 'fill' because the entire contents of the
+	 * SSDT is build by calling this method on all devices.
+	 *
 	 * @dev: Device to write
 	 * @ctx: ACPI context to use
 	 * @return 0 if OK, -ve on error
 	 */
 	int (*fill_ssdt)(const struct udevice *dev, struct acpi_ctx *ctx);
+
+	/**
+	 * inject_dsdt() - Generate DSDT code for a device
+	 *
+	 * This is called to create the DSDT code. The method should write out
+	 * whatever ACPI code is needed by this device. It will end up in the
+	 * DSDT table.
+	 *
+	 * Note that this is called 'inject' because the output of calling this
+	 * method on all devices is injected into the DSDT, the bulk of which
+	 * is writte in .asl files for the board.
+	 *
+	 * @dev: Device to write
+	 * @ctx: ACPI context to use
+	 * @return 0 if OK, -ve on error
+	 */
+	int (*inject_dsdt)(const struct udevice *dev, struct acpi_ctx *ctx);
 };
 
 #define device_get_acpi_ops(dev)	((dev)->driver->acpi_ops)
@@ -141,6 +161,16 @@  int acpi_write_dev_tables(struct acpi_ctx *ctx);
  */
 int acpi_fill_ssdt(struct acpi_ctx *ctx);
 
+/**
+ * acpi_inject_dsdt() - Generate ACPI tables for DSDT
+ *
+ * This is called to create the DSDT code for all devices.
+ *
+ * @ctx: ACPI context to use
+ * @return 0 if OK, -ve on error
+ */
+int acpi_inject_dsdt(struct acpi_ctx *ctx);
+
 #endif /* __ACPI__ */
 
 #endif
diff --git a/test/dm/acpi.c b/test/dm/acpi.c
index 4e1d401e0d..1abde65c8c 100644
--- a/test/dm/acpi.c
+++ b/test/dm/acpi.c
@@ -81,10 +81,24 @@  static int testacpi_fill_ssdt(const struct udevice *dev, struct acpi_ctx *ctx)
 	return 0;
 }
 
+static int testacpi_inject_dsdt(const struct udevice *dev, struct acpi_ctx *ctx)
+{
+	const char *data;
+
+	data = dev_read_string(dev, "acpi-dsdt-test-data");
+	if (data) {
+		while (*data)
+			acpigen_emit_byte(ctx, *data++);
+	}
+
+	return 0;
+}
+
 struct acpi_ops testacpi_ops = {
 	.get_name	= testacpi_get_name,
 	.write_tables	= testacpi_write_tables,
 	.fill_ssdt	= testacpi_fill_ssdt,
+	.inject_dsdt	= testacpi_inject_dsdt,
 };
 
 static const struct udevice_id testacpi_ids[] = {
@@ -441,3 +455,33 @@  static int dm_test_acpi_fill_ssdt(struct unit_test_state *uts)
 	return 0;
 }
 DM_TEST(dm_test_acpi_fill_ssdt, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/* Test acpi_inject_dsdt() */
+static int dm_test_acpi_inject_dsdt(struct unit_test_state *uts)
+{
+	struct acpi_ctx ctx;
+	u8 *buf;
+
+	buf = malloc(BUF_SIZE);
+	ut_assertnonnull(buf);
+
+	ctx.current = buf;
+	buf[4] = 'z';	/* sentinel */
+	ut_assertok(acpi_inject_dsdt(&ctx));
+
+	/*
+	 * These values come from acpi-test's acpi-dsdt-test-data property.
+	 * There is no u-boot,acpi-dsdt-order so device-tree order is used.
+	 */
+	ut_asserteq('h', buf[0]);
+	ut_asserteq('i', buf[1]);
+
+	/* These values come from acpi-test's acpi-dsdt-test-data property */
+	ut_asserteq('j', buf[2]);
+	ut_asserteq('k', buf[3]);
+
+	ut_asserteq('z', buf[4]);
+
+	return 0;
+}
+DM_TEST(dm_test_acpi_inject_dsdt, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);