| Message ID | 20200311172014.33052-5-shameerali.kolothum.thodi@huawei.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | ARM virt: Add NVDIMM support | expand |
On Wed, 11 Mar 2020 17:20:08 +0000 Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> wrote: > As per ACPI spec 6.3, Table 19-419 Object Conversion Rules, if > the Buffer Field <= to the size of an Integer (in bits), it will > be treated as an integer. Moreover, the integer size depends on > DSDT tables revision number. If revision number is < 2, integer > size is 32 bits, otherwise it is 64 bits. Current NVDIMM common > DSM aml code (NCAL) uses CreateField() for creating DSM output > buffer. This creates an issue in arm/virt platform where DSDT > revision number is 2 and results in DSM buffer with a wrong > size(8 bytes) gets returned when actual length is < 8 bytes. > This causes guest kernel to report, > > "nfit ACPI0012:00: found a zero length table '0' parsing nfit" > > In order to fix this, aml code is now modified such that it builds > the DSM output buffer in a byte by byte fashion when length is > smaller than Integer size. > > Suggested-by: Igor Mammedov <imammedo@redhat.com> > Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Reviewed-by: Igor Mammedov <imammedo@redhat.com> > --- > v2 -> v3 > - Using Integer size as 8 bytes instead of SizeOf(Integer) > --- > hw/acpi/nvdimm.c | 40 +++++++++++++++++++-- > tests/qtest/bios-tables-test-allowed-diff.h | 2 ++ > 2 files changed, 39 insertions(+), 3 deletions(-) > > diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c > index 5219dd0e2e..213556f35d 100644 > --- a/hw/acpi/nvdimm.c > +++ b/hw/acpi/nvdimm.c > @@ -938,6 +938,7 @@ static void nvdimm_build_common_dsm(Aml *dev) > Aml *method, *ifctx, *function, *handle, *uuid, *dsm_mem, *elsectx2; > Aml *elsectx, *unsupport, *unpatched, *expected_uuid, *uuid_invalid; > Aml *pckg, *pckg_index, *pckg_buf, *field, *dsm_out_buf, *dsm_out_buf_size; > + Aml *whilectx, *offset; > uint8_t byte_list[1]; > > method = aml_method(NVDIMM_COMMON_DSM, 5, AML_SERIALIZED); > @@ -1091,13 +1092,46 @@ static void nvdimm_build_common_dsm(Aml *dev) > /* RLEN is not included in the payload returned to guest. */ > aml_append(method, aml_subtract(aml_name(NVDIMM_DSM_OUT_BUF_SIZE), > aml_int(4), dsm_out_buf_size)); > + > + /* > + * As per ACPI spec 6.3, Table 19-419 Object Conversion Rules, if > + * the Buffer Field <= to the size of an Integer (in bits), it will > + * be treated as an integer. Moreover, the integer size depends on > + * DSDT tables revision number. If revision number is < 2, integer > + * size is 32 bits, otherwise it is 64 bits. > + * Because of this CreateField() canot be used if RLEN < Integer Size. > + * > + * Also please note that APCI ASL operator SizeOf() doesn't support > + * Integer and there isn't any other way to figure out the Integer > + * size. Hence we assume 8 byte as Integer size and if RLEN < 8 bytes, > + * build dsm_out_buf byte by byte. > + */ > + ifctx = aml_if(aml_lless(dsm_out_buf_size, aml_int(8))); > + offset = aml_local(2); > + aml_append(ifctx, aml_store(aml_int(0), offset)); > + aml_append(ifctx, aml_name_decl("TBUF", aml_buffer(1, NULL))); > + aml_append(ifctx, aml_store(aml_buffer(0, NULL), dsm_out_buf)); > + > + whilectx = aml_while(aml_lless(offset, dsm_out_buf_size)); > + /* Copy 1 byte at offset from ODAT to temporary buffer(TBUF). */ > + aml_append(whilectx, aml_store(aml_derefof(aml_index( > + aml_name(NVDIMM_DSM_OUT_BUF), offset)), > + aml_index(aml_name("TBUF"), aml_int(0)))); > + aml_append(whilectx, aml_concatenate(dsm_out_buf, aml_name("TBUF"), > + dsm_out_buf)); > + aml_append(whilectx, aml_increment(offset)); > + aml_append(ifctx, whilectx); > + > + aml_append(ifctx, aml_return(dsm_out_buf)); > + aml_append(method, ifctx); > + > + /* If RLEN >= Integer size, just use CreateField() operator */ > aml_append(method, aml_store(aml_shiftleft(dsm_out_buf_size, aml_int(3)), > dsm_out_buf_size)); > aml_append(method, aml_create_field(aml_name(NVDIMM_DSM_OUT_BUF), > aml_int(0), dsm_out_buf_size, "OBUF")); > - aml_append(method, aml_concatenate(aml_buffer(0, NULL), aml_name("OBUF"), > - dsm_out_buf)); > - aml_append(method, aml_return(dsm_out_buf)); > + aml_append(method, aml_return(aml_name("OBUF"))); > + > aml_append(dev, method); > } > > diff --git a/tests/qtest/bios-tables-test-allowed-diff.h b/tests/qtest/bios-tables-test-allowed-diff.h > index dfb8523c8b..eb8bae1407 100644 > --- a/tests/qtest/bios-tables-test-allowed-diff.h > +++ b/tests/qtest/bios-tables-test-allowed-diff.h > @@ -1 +1,3 @@ > /* List of comma-separated changed AML files to ignore */ > +"tests/data/acpi/pc/SSDT.dimmpxm", > +"tests/data/acpi/q35/SSDT.dimmpxm",
diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c index 5219dd0e2e..213556f35d 100644 --- a/hw/acpi/nvdimm.c +++ b/hw/acpi/nvdimm.c @@ -938,6 +938,7 @@ static void nvdimm_build_common_dsm(Aml *dev) Aml *method, *ifctx, *function, *handle, *uuid, *dsm_mem, *elsectx2; Aml *elsectx, *unsupport, *unpatched, *expected_uuid, *uuid_invalid; Aml *pckg, *pckg_index, *pckg_buf, *field, *dsm_out_buf, *dsm_out_buf_size; + Aml *whilectx, *offset; uint8_t byte_list[1]; method = aml_method(NVDIMM_COMMON_DSM, 5, AML_SERIALIZED); @@ -1091,13 +1092,46 @@ static void nvdimm_build_common_dsm(Aml *dev) /* RLEN is not included in the payload returned to guest. */ aml_append(method, aml_subtract(aml_name(NVDIMM_DSM_OUT_BUF_SIZE), aml_int(4), dsm_out_buf_size)); + + /* + * As per ACPI spec 6.3, Table 19-419 Object Conversion Rules, if + * the Buffer Field <= to the size of an Integer (in bits), it will + * be treated as an integer. Moreover, the integer size depends on + * DSDT tables revision number. If revision number is < 2, integer + * size is 32 bits, otherwise it is 64 bits. + * Because of this CreateField() canot be used if RLEN < Integer Size. + * + * Also please note that APCI ASL operator SizeOf() doesn't support + * Integer and there isn't any other way to figure out the Integer + * size. Hence we assume 8 byte as Integer size and if RLEN < 8 bytes, + * build dsm_out_buf byte by byte. + */ + ifctx = aml_if(aml_lless(dsm_out_buf_size, aml_int(8))); + offset = aml_local(2); + aml_append(ifctx, aml_store(aml_int(0), offset)); + aml_append(ifctx, aml_name_decl("TBUF", aml_buffer(1, NULL))); + aml_append(ifctx, aml_store(aml_buffer(0, NULL), dsm_out_buf)); + + whilectx = aml_while(aml_lless(offset, dsm_out_buf_size)); + /* Copy 1 byte at offset from ODAT to temporary buffer(TBUF). */ + aml_append(whilectx, aml_store(aml_derefof(aml_index( + aml_name(NVDIMM_DSM_OUT_BUF), offset)), + aml_index(aml_name("TBUF"), aml_int(0)))); + aml_append(whilectx, aml_concatenate(dsm_out_buf, aml_name("TBUF"), + dsm_out_buf)); + aml_append(whilectx, aml_increment(offset)); + aml_append(ifctx, whilectx); + + aml_append(ifctx, aml_return(dsm_out_buf)); + aml_append(method, ifctx); + + /* If RLEN >= Integer size, just use CreateField() operator */ aml_append(method, aml_store(aml_shiftleft(dsm_out_buf_size, aml_int(3)), dsm_out_buf_size)); aml_append(method, aml_create_field(aml_name(NVDIMM_DSM_OUT_BUF), aml_int(0), dsm_out_buf_size, "OBUF")); - aml_append(method, aml_concatenate(aml_buffer(0, NULL), aml_name("OBUF"), - dsm_out_buf)); - aml_append(method, aml_return(dsm_out_buf)); + aml_append(method, aml_return(aml_name("OBUF"))); + aml_append(dev, method); } diff --git a/tests/qtest/bios-tables-test-allowed-diff.h b/tests/qtest/bios-tables-test-allowed-diff.h index dfb8523c8b..eb8bae1407 100644 --- a/tests/qtest/bios-tables-test-allowed-diff.h +++ b/tests/qtest/bios-tables-test-allowed-diff.h @@ -1 +1,3 @@ /* List of comma-separated changed AML files to ignore */ +"tests/data/acpi/pc/SSDT.dimmpxm", +"tests/data/acpi/q35/SSDT.dimmpxm",
As per ACPI spec 6.3, Table 19-419 Object Conversion Rules, if the Buffer Field <= to the size of an Integer (in bits), it will be treated as an integer. Moreover, the integer size depends on DSDT tables revision number. If revision number is < 2, integer size is 32 bits, otherwise it is 64 bits. Current NVDIMM common DSM aml code (NCAL) uses CreateField() for creating DSM output buffer. This creates an issue in arm/virt platform where DSDT revision number is 2 and results in DSM buffer with a wrong size(8 bytes) gets returned when actual length is < 8 bytes. This causes guest kernel to report, "nfit ACPI0012:00: found a zero length table '0' parsing nfit" In order to fix this, aml code is now modified such that it builds the DSM output buffer in a byte by byte fashion when length is smaller than Integer size. Suggested-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> --- v2 -> v3 - Using Integer size as 8 bytes instead of SizeOf(Integer) --- hw/acpi/nvdimm.c | 40 +++++++++++++++++++-- tests/qtest/bios-tables-test-allowed-diff.h | 2 ++ 2 files changed, 39 insertions(+), 3 deletions(-) -- 2.17.1