---

yaml --- r: 158073 b: refs/heads/master c: 93f1cc6 h: refs/heads/master i: 158071: fc5f9a1 v: v3
git-mirror · Sep 3, 2009 · 7d61423 · 7d61423
1 parent f9efde6
commit 7d61423
Show file tree

Hide file tree

Showing 3 changed files with 19 additions and 6 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d586d7852ccd0cecb502bf4809f827e60c486af0
+refs/heads/master: 93f1cc67cf3196174412adca87321b25c1c986b0
diff --git a/trunk/arch/x86/include/asm/amd_iommu_types.h b/trunk/arch/x86/include/asm/amd_iommu_types.h
@@ -457,4 +457,7 @@ static inline void amd_iommu_stats_init(void) { }
 
 #endif /* CONFIG_AMD_IOMMU_STATS */
 
+/* some function prototypes */
+extern void amd_iommu_reset_cmd_buffer(struct amd_iommu *iommu);
+
 #endif /* _ASM_X86_AMD_IOMMU_TYPES_H */
diff --git a/trunk/arch/x86/kernel/amd_iommu_init.c b/trunk/arch/x86/kernel/amd_iommu_init.c
@@ -434,6 +434,20 @@ static u8 * __init alloc_command_buffer(struct amd_iommu *iommu)
 	return cmd_buf;
 }
 
+/*
+ * This function resets the command buffer if the IOMMU stopped fetching
+ * commands from it.
+ */
+void amd_iommu_reset_cmd_buffer(struct amd_iommu *iommu)
+{
+	iommu_feature_disable(iommu, CONTROL_CMDBUF_EN);
+
+	writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET);
+	writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
+
+	iommu_feature_enable(iommu, CONTROL_CMDBUF_EN);
+}
+
 /*
  * This function writes the command buffer address to the hardware and
  * enables it.
@@ -450,11 +464,7 @@ static void iommu_enable_command_buffer(struct amd_iommu *iommu)
 	memcpy_toio(iommu->mmio_base + MMIO_CMD_BUF_OFFSET,
 		    &entry, sizeof(entry));
 
-	/* set head and tail to zero manually */
-	writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET);
-	writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
-
-	iommu_feature_enable(iommu, CONTROL_CMDBUF_EN);
+	amd_iommu_reset_cmd_buffer(iommu);
 }
 
 static void __init free_command_buffer(struct amd_iommu *iommu)