[RFC,07/17] hw/acpi/aml-build: add function for i2c slave device serial bus description

Commit Message

Jonathan Cameron July 17, 2023, 5:16 p.m. UTC

Needed for later patches that add MCTP over I2C support to both
x86 and ARM boards.

Signed-off-by: Jonathan Cameron <[e-mail]>
---
 include/hw/acpi/aml-build.h |  1 +
 hw/acpi/aml-build.c         | 17 +++++++++++++++++
 2 files changed, 18 insertions(+)

Patch

diff --git a/include/hw/acpi/aml-build.h b/include/hw/acpi/aml-build.h
index fc2b949fb5..28db028b17 100644
--- a/include/hw/acpi/aml-build.h
+++ b/include/hw/acpi/aml-build.h
@@ -382,6 +382,7 @@  Aml *aml_dma(AmlDmaType typ, AmlDmaBusMaster bm, AmlTransferSize sz,
              uint8_t channel);
 Aml *aml_sleep(uint64_t msec);
 Aml *aml_i2c_serial_bus_device(uint16_t address, const char *resource_source);
+Aml *aml_i2c_slv_serial_bus_device(uint16_t address, const char *resource_source);
 
 /* Block AML object primitives */
 Aml *aml_scope(const char *name_format, ...) G_GNUC_PRINTF(1, 2);
diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
index 918cbb5b9d..22d7ecd753 100644
--- a/hw/acpi/aml-build.c
+++ b/hw/acpi/aml-build.c
@@ -2478,3 +2478,20 @@  Aml *aml_i2c_serial_bus_device(uint16_t address, const char *resource_source)
 
     return var;
 }
+
+/* ACPI 5.0: 6.4.3.8.2.1 I2C Serial Bus Connection Resource Descriptor */
+Aml *aml_i2c_slv_serial_bus_device(uint16_t address, const char *resource_source)
+{
+    uint16_t resource_source_len = strlen(resource_source) + 1;
+    Aml *var = aml_serial_bus_device(AML_SERIAL_BUS_TYPE_I2C, 1, 0, 1,
+                                     6, resource_source_len);
+
+    /* Connection Speed.  Just set to 100K for now, it doesn't really matter. */
+    build_append_int_noprefix(var->buf, 100000, 4);
+    build_append_int_noprefix(var->buf, address, sizeof(address));
+
+    /* This is a string, not a name, so just copy it directly in. */
+    g_array_append_vals(var->buf, resource_source, resource_source_len);
+
+    return var;
+}