Re: [Qemu-devel] [PATCH v3 07/13] tests: acpi: add acpi_find_rsdp_address_uefi() helper

[Igor Mammedov <imammedo@redhat.com>]

On Thu, 25 Apr 2019 16:00:46 +0800
Wei Yang <richardw.yang@linux.intel.com> wrote:

> On Thu, Apr 25, 2019 at 07:34:43AM +0200, Igor Mammedov wrote:
> >introduce UEFI specific counterpart to acpi_find_rsdp_address()
> >that will help to find RSDP address when [OA]VMF is used as
> >firmware. It requires guest firmware or other guest app to place
> >1Mb aligned UefiTestSupport structure (defined in this patch)
> >in RAM with UefiTestSupport::signature_guid set to
> >AB87A6B1-2034-BDA0-71BD-375007757785  
> 
> Just curious about where we get this signature? Randomly generated?

something like this, see 09a274d82f, I'll add commit id here for reference

> 
> >
> >Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> >Reviewed-by: Laszlo Ersek <lersek@redhat.com>  
> 
> Reviewed-by: Wei Yang <richardw.yang@linux.intel.com>
> 
> >---
> >v3:
> >  * fix checkpatch error (separate opening brace from values in AcpiTestSupportGuid initializer)
> >v2:
> >  * Laszlo Ersek <lersek@redhat.com>
> >    - s/uefi_find_rsdp_addr/acpi_find_rsdp_address_uefi/
> >    - use GUID_SIZE instead of opencodding size
> >    - make AcpiTestSupportGuid const
> >    - s/TCI/TCG/
> >---
> > tests/acpi-utils.h |  2 ++
> > tests/acpi-utils.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
> > 2 files changed, 46 insertions(+)
> >
> >diff --git a/tests/acpi-utils.h b/tests/acpi-utils.h
> >index 75f78f2..dcfa721 100644
> >--- a/tests/acpi-utils.h
> >+++ b/tests/acpi-utils.h
> >@@ -46,6 +46,8 @@ typedef struct {
> > 
> > uint8_t acpi_calc_checksum(const uint8_t *data, int len);
> > uint32_t acpi_find_rsdp_address(QTestState *qts);
> >+uint64_t acpi_find_rsdp_address_uefi(QTestState *qts, uint64_t start,
> >+                                     uint64_t size);
> > void acpi_fetch_rsdp_table(QTestState *qts, uint64_t addr, uint8_t *rsdp_table);
> > void acpi_fetch_table(QTestState *qts, uint8_t **aml, uint32_t *aml_len,
> >                       const uint8_t *addr_ptr, const char *sig,
> >diff --git a/tests/acpi-utils.c b/tests/acpi-utils.c
> >index 2dd4fe0..197af82 100644
> >--- a/tests/acpi-utils.c
> >+++ b/tests/acpi-utils.c
> >@@ -99,3 +99,47 @@ void acpi_fetch_table(QTestState *qts, uint8_t **aml, uint32_t *aml_len,
> >         g_assert(!acpi_calc_checksum(*aml, *aml_len));
> >     }
> > }
> >+
> >+#define GUID_SIZE 16
> >+static const uint8_t AcpiTestSupportGuid[GUID_SIZE] = {
> >+       0xb1, 0xa6, 0x87, 0xab,
> >+       0x34, 0x20,
> >+       0xa0, 0xbd,
> >+       0x71, 0xbd, 0x37, 0x50, 0x07, 0x75, 0x77, 0x85 };
> >+
> >+typedef struct {
> >+    uint8_t signature_guid[GUID_SIZE];
> >+    uint64_t rsdp10;
> >+    uint64_t rsdp20;
> >+} __attribute__((packed)) UefiTestSupport;
> >+
> >+/* Wait at most 600 seconds (test is slow with TCG and --enable-debug) */
> >+#define TEST_DELAY (1 * G_USEC_PER_SEC / 10)
> >+#define TEST_CYCLES MAX((600 * G_USEC_PER_SEC / TEST_DELAY), 1)
> >+#define MB 0x100000ULL
> >+uint64_t acpi_find_rsdp_address_uefi(QTestState *qts, uint64_t start,
> >+                                     uint64_t size)
> >+{
> >+    int i, j;
> >+    uint8_t data[GUID_SIZE];
> >+
> >+    for (i = 0; i < TEST_CYCLES; ++i) {
> >+        for (j = 0; j < size / MB; j++) {
> >+            /* look for GUID at every 1Mb block */
> >+            uint64_t addr = start + j * MB;
> >+
> >+            qtest_memread(qts, addr, data, sizeof(data));
> >+            if (!memcmp(AcpiTestSupportGuid, data, sizeof(data))) {
> >+                UefiTestSupport ret;
> >+
> >+                qtest_memread(qts, addr, &ret, sizeof(ret));
> >+                ret.rsdp10 = le64_to_cpu(ret.rsdp10);
> >+                ret.rsdp20 = le64_to_cpu(ret.rsdp20);
> >+                return ret.rsdp20 ? ret.rsdp20 : ret.rsdp10;
> >+            }
> >+        }
> >+        g_usleep(TEST_DELAY);
> >+    }
> >+    g_assert_not_reached();
> >+    return 0;
> >+}
> >-- 
> >2.7.4  
>