Introduce RAM locations in the vendor specific area in the TIS. These
locations will survive a reset and will be part of the state written
during a suspend. Their puspose is to support the physical presence
interface where the OS (ACPI) and the firmware (SeaBIOS) use these RAM
locations to exchange data.
Only locality 0 is used, leaving localities 1-4 available for other extensions.
Signed-off-by: Stefan Berger <stef...@linux.vnet.ibm.com>
---
hw/tpm/tpm_tis.c | 27 +++++++++++++++++++++++++++
hw/tpm/tpm_tis.h | 2 ++
2 files changed, 29 insertions(+)
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
index daf2ac9..1fb4e17 100644
--- a/hw/tpm/tpm_tis.c
+++ b/hw/tpm/tpm_tis.c
@@ -61,6 +61,7 @@
/* vendor-specific registers */
#define TPM_TIS_REG_DEBUG 0xf90
+#define TPM_TIS_REG_RAM 0xfa0
#define TPM_TIS_STS_TPM_FAMILY_MASK (0x3 << 26)/* TPM 2.0 */
#define TPM_TIS_STS_TPM_FAMILY1_2 (0 << 26) /* TPM 2.0 */
@@ -503,6 +504,7 @@ static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr addr,
uint8_t locty = tpm_tis_locality_from_addr(addr);
uint32_t avail;
uint8_t v;
+ int c;
if (tpm_backend_had_startup_error(s->be_driver)) {
return val;
@@ -599,6 +601,18 @@ static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr
addr,
tpm_tis_dump_state(opaque, addr);
break;
#endif
+ case TPM_TIS_REG_RAM ... 0xfff:
+ if (locty == 0) {
+ /* RAM only in locality 0 -- allow unaligned accesses */
+ offset = addr & 0xfff;
+ shift = 0;
+
+ for (c = size - 1; c >= 0; c--) {
+ val <<= 8;
+ val |= tis->locty0_ram[offset - TPM_TIS_REG_RAM + c];
+ }
+ }
+ break;
}
if (shift) {
@@ -938,6 +952,19 @@ static void tpm_tis_mmio_write_intern(void *opaque, hwaddr
addr,
}
}
break;
+
+ case TPM_TIS_REG_RAM ... 0xfff:
+ if (locty == 0) {
+ /* RAM only in locality 0 -- allow unaligned accesses */
+ off = addr & 0xfff;
+ val >>= shift;
+ /* only support locality 0 */
+ for (c = 0; c <= size - 1; c++) {
+ tis->locty0_ram[off - TPM_TIS_REG_RAM + c] = val;
+ val >>= 8;
+ }
+ }
+ break;
}
}
diff --git a/hw/tpm/tpm_tis.h b/hw/tpm/tpm_tis.h
index a1df41f..0e98cb0 100644
--- a/hw/tpm/tpm_tis.h
+++ b/hw/tpm/tpm_tis.h
@@ -65,6 +65,8 @@ typedef struct TPMTISEmuState {
qemu_irq irq;
uint32_t irq_num;
+
+ uint8_t locty0_ram[0x60]; /* a vendor spec. extension at 0xfa0-0xfff in
locality 0 */
} TPMTISEmuState;
#endif /* TPM_TPM_TIS_H */
--
1.9.3
