_FIT is required for hotplug support, guest will inquire the updated
device info from it if a hotplug event is received
As FIT buffer is not completely mapped into guest address space, so a
new function, Read FIT whose function index is 0xFFFFFFFF, is reserved
by QEMU to read the piece of FIT buffer. The buffer is concatenated
before _FIT return
Refer to docs/specs/acpi-nvdimm.txt for detailed design
Signed-off-by: Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx>
---
hw/acpi/nvdimm.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 82 insertions(+)
diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
index 0e2b9f0..4bbd1e7 100644
--- a/hw/acpi/nvdimm.c
+++ b/hw/acpi/nvdimm.c
@@ -886,6 +886,87 @@ static void nvdimm_build_device_dsm(Aml *dev, uint32_t handle)
aml_append(dev, method);
}
+static void nvdimm_build_fit(Aml *dev)
+{
+ Aml *method, *pkg, *buf, *buf_size, *offset, *call_result;
+ Aml *whilectx, *ifcond, *ifctx, *fit;
+
+ buf = aml_local(0);
+ buf_size = aml_local(1);
+ fit = aml_local(2);
+
+ /* build helper function, RFIT. */
+ method = aml_method("RFIT", 1, AML_NOTSERIALIZED);
+ aml_append(method, aml_create_dword_field(aml_buffer(4, NULL),
+ aml_int(0), "OFST"));
+
+ /* prepare input package. */
+ pkg = aml_package(1);
+ aml_append(method, aml_store(aml_arg(0), aml_name("OFST")));
+ aml_append(pkg, aml_name("OFST"));
+
+ /* call Read_FIT function. */
+ call_result = aml_call5(NVDIMM_COMMON_DSM,
+ aml_touuid("2F10E7A4-9E91-11E4-89D3-123B93F75CBA"
+ /* UUID for NVDIMM Root Device */),
+ aml_int(1) /* Revision 1 */,
+ aml_int(0xFFFFFFFF) /* Read FIT. */,
+ pkg, aml_int(0) /* for root device. */);
+ aml_append(method, aml_store(call_result, buf));
+
+ /* handle _DSM result. */
+ aml_append(method, aml_create_dword_field(buf,
+ aml_int(0) /* offset at byte 0 */, "STAU"));
+
+ /* if something is wrong during _DSM. */
+ ifcond = aml_equal(aml_int(0 /* Success */), aml_name("STAU"));
+ ifctx = aml_if(aml_lnot(ifcond));
+ aml_append(ifctx, aml_return(aml_buffer(0, NULL)));
+ aml_append(method, ifctx);
+
+ aml_append(method, aml_store(aml_sizeof(buf), buf_size));
+ aml_append(method, aml_subtract(buf_size,
+ aml_int(4) /* the size of "STAU" */,
+ buf_size));
+
+ /* if we read the end of fit. */
+ ifctx = aml_if(aml_equal(buf_size, aml_int(0)));
+ aml_append(ifctx, aml_return(aml_buffer(0, NULL)));
+ aml_append(method, ifctx);
+
+ aml_append(method, aml_store(aml_shiftleft(buf_size, aml_int(3)),
+ buf_size));
+ aml_append(method, aml_create_field(buf,
+ aml_int(4 * BITS_PER_BYTE), /* offset at byte 4.*/
+ buf_size, "BUFF"));
+ aml_append(method, aml_return(aml_name("BUFF")));
+ aml_append(dev, method);
+
+ /* build _FIT. */
+ method = aml_method("_FIT", 0, AML_NOTSERIALIZED);
+ offset = aml_local(3);
+
+ aml_append(method, aml_store(aml_buffer(0, NULL), fit));
+ aml_append(method, aml_store(aml_int(0), offset));
+
+ whilectx = aml_while(aml_int(1));
+ aml_append(whilectx, aml_store(aml_call1("RFIT", offset), buf));
+ aml_append(whilectx, aml_store(aml_sizeof(buf), buf_size));
+
+ /* finish fit read if no data is read out. */
+ ifctx = aml_if(aml_equal(buf_size, aml_int(0)));
+ aml_append(ifctx, aml_return(fit));
+ aml_append(whilectx, ifctx);
+
+ /* update the offset. */
+ aml_append(whilectx, aml_add(offset, buf_size, offset));
+ /* append the data we read out to the fit buffer. */
+ aml_append(whilectx, aml_concatenate(fit, buf, fit));
+ aml_append(method, whilectx);
+
+ aml_append(dev, method);
+}
+
static void nvdimm_build_nvdimm_devices(Aml *root_dev, uint32_t ram_slots)
{
uint32_t slot;
@@ -1001,6 +1082,7 @@ static void nvdimm_build_ssdt(GArray *table_offsets, GArray *table_data,
/* 0 is reserved for root device. */
nvdimm_build_device_dsm(dev, 0);
+ nvdimm_build_fit(dev);
nvdimm_build_nvdimm_devices(dev, ram_slots);
--
1.8.3.1
--
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