[Qemu-devel] [PATCH v3 02/19] libqos/ahci: Add ahci_port_clear helper

[John Snow <jsnow@redhat.com>]

Add a helper that assists in clearing out potentially old error and FIS
information from an AHCI port's data structures. This ensures we always
start with a blank slate for interrupt and FIS receipt information.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
---
 tests/ahci-test.c   |  9 ++-------
 tests/libqos/ahci.c | 16 ++++++++++++++++
 tests/libqos/ahci.h |  1 +
 3 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/tests/ahci-test.c b/tests/ahci-test.c
index c689b62..90647f2 100644
--- a/tests/ahci-test.c
+++ b/tests/ahci-test.c
@@ -687,13 +687,8 @@ static void ahci_test_identify(AHCIQState *ahci)
     i = ahci_port_select(ahci);
     g_test_message("Selected port %u for test", i);
 
-    /* Clear out this port's interrupts (ignore the init register d2h fis) */
-    reg = ahci_px_rreg(ahci, i, AHCI_PX_IS);
-    ahci_px_wreg(ahci, i, AHCI_PX_IS, reg);
-    g_assert_cmphex(ahci_px_rreg(ahci, i, AHCI_PX_IS), ==, 0);
-
-    /* Wipe the FIS-Receive Buffer */
-    qmemset(ahci->port[i].fb, 0x00, 0x100);
+    /* Clear out the FIS Receive area and any pending interrupts. */
+    ahci_port_clear(ahci, i);
 
     /* Create a Command Table buffer. 0x80 is the smallest with a PRDTL of 0. */
     /* We need at least one PRD, so round up to the nearest 0x80 multiple.    */
diff --git a/tests/libqos/ahci.c b/tests/libqos/ahci.c
index 8874790..af2eb97 100644
--- a/tests/libqos/ahci.c
+++ b/tests/libqos/ahci.c
@@ -294,3 +294,19 @@ unsigned ahci_port_select(AHCIQState *ahci)
     g_assert(i < 32);
     return i;
 }
+
+/**
+ * Clear a port's interrupts and status information prior to a test.
+ */
+void ahci_port_clear(AHCIQState *ahci, uint8_t port)
+{
+    uint32_t reg;
+
+    /* Clear out this port's interrupts (ignore the init register d2h fis) */
+    reg = ahci_px_rreg(ahci, port, AHCI_PX_IS);
+    ahci_px_wreg(ahci, port, AHCI_PX_IS, reg);
+    g_assert_cmphex(ahci_px_rreg(ahci, port, AHCI_PX_IS), ==, 0);
+
+    /* Wipe the FIS-Recieve Buffer */
+    qmemset(ahci->port[port].fb, 0x00, 0x100);
+}
diff --git a/tests/libqos/ahci.h b/tests/libqos/ahci.h
index b3992e1..39ba94e 100644
--- a/tests/libqos/ahci.h
+++ b/tests/libqos/ahci.h
@@ -432,5 +432,6 @@ void ahci_pci_enable(AHCIQState *ahci);
 void start_ahci_device(AHCIQState *ahci);
 void ahci_hba_enable(AHCIQState *ahci);
 unsigned ahci_port_select(AHCIQState *ahci);
+void ahci_port_clear(AHCIQState *ahci, uint8_t port);
 
 #endif
-- 
1.9.3