5 files changed, 41 insertions, 0 deletions
diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
index 012ec686d4..3087acc4ab 100644
--- a/hw/tpm/tpm_crb.c
+++ b/hw/tpm/tpm_crb.c
@@ -233,6 +233,9 @@ static void tpm_crb_reset(void *dev)
 {
     CRBState *s = CRB(dev);
 
+    if (s->ppi_enabled) {
+        tpm_ppi_reset(&s->ppi);
+    }
     tpm_backend_reset(s->tpmbe);
 
     memset(s->regs, 0, sizeof(s->regs));
diff --git a/hw/tpm/tpm_ppi.c b/hw/tpm/tpm_ppi.c
index cf17779c20..cd8205f212 100644
--- a/hw/tpm/tpm_ppi.c
+++ b/hw/tpm/tpm_ppi.c
@@ -16,8 +16,30 @@
 #include "qapi/error.h"
 #include "cpu.h"
 #include "sysemu/memory_mapping.h"
+#include "sysemu/reset.h"
 #include "migration/vmstate.h"
 #include "tpm_ppi.h"
+#include "trace.h"
+
+void tpm_ppi_reset(TPMPPI *tpmppi)
+{
+    if (tpmppi->buf[0x15a /* movv, docs/specs/tpm.txt */] & 0x1) {
+        GuestPhysBlockList guest_phys_blocks;
+        GuestPhysBlock *block;
+
+        guest_phys_blocks_init(&guest_phys_blocks);
+        guest_phys_blocks_append(&guest_phys_blocks);
+        QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) {
+            trace_tpm_ppi_memset(block->host_addr,
+                                 block->target_end - block->target_start);
+            memset(block->host_addr, 0,
+                   block->target_end - block->target_start);
+            memory_region_set_dirty(block->mr, 0,
+                                    block->target_end - block->target_start);
+        }
+        guest_phys_blocks_free(&guest_phys_blocks);
+    }
+}
 
 void tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
                   hwaddr addr, Object *obj)
diff --git a/hw/tpm/tpm_ppi.h b/hw/tpm/tpm_ppi.h
index c5e555fe2c..d33ef27de6 100644
--- a/hw/tpm/tpm_ppi.h
+++ b/hw/tpm/tpm_ppi.h
@@ -33,4 +33,14 @@ typedef struct TPMPPI {
 void tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
                   hwaddr addr, Object *obj);
 
+/**
+ * tpm_ppi_reset:
+ * @tpmppi: a TPMPPI
+ *
+ * Function to call on machine reset. It will check if the "Memory
+ * overwrite" variable is set, and perform a memory clear on volatile
+ * memory if requested.
+ **/
+void tpm_ppi_reset(TPMPPI *tpmppi);
+
 #endif /* TPM_TPM_PPI_H */
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
index 02d9d5c911..fd6bb9b59a 100644
--- a/hw/tpm/tpm_tis.c
+++ b/hw/tpm/tpm_tis.c
@@ -872,6 +872,9 @@ static void tpm_tis_reset(DeviceState *dev)
     s->be_buffer_size = MIN(tpm_backend_get_buffer_size(s->be_driver),
                             TPM_TIS_BUFFER_MAX);
 
+    if (s->ppi_enabled) {
+        tpm_ppi_reset(&s->ppi);
+    }
     tpm_backend_reset(s->be_driver);
 
     s->active_locty = TPM_TIS_NO_LOCALITY;
diff --git a/hw/tpm/trace-events b/hw/tpm/trace-events
index 25bee0cecf..920d32ad55 100644
--- a/hw/tpm/trace-events
+++ b/hw/tpm/trace-events
@@ -51,3 +51,6 @@ tpm_tis_mmio_write_init_abort(void) "Initiating abort"
 tpm_tis_mmio_write_lowering_irq(void) "Lowering IRQ"
 tpm_tis_mmio_write_data2send(uint32_t value, unsigned size) "Data to send to TPM: 0x%08x (size=%d)"
 tpm_tis_pre_save(uint8_t locty, uint32_t rw_offset) "locty: %d, rw_offset = %u"
+
+# hw/tpm/tpm_ppi.c
+tpm_ppi_memset(uint8_t *ptr, size_t size) "memset: %p %zu"