[PATCH v9 02/13] iommu/amd: add several helper functions

Baoquan He
2017-08-01T11:37:42Z

Move single iommu enabling codes into a wrapper function early_enable_iommu().
This can make later kdump change easier.

And also add iommu_disable_command_buffer and iommu_disable_event_buffer
for later usage.

Signed-off-by: Baoquan He <bhe@redhat.com>
---
drivers/iommu/amd_iommu_init.c | 42 +++++++++++++++++++++++++++++++-----------
1 file changed, 31 insertions(+), 11 deletions(-)

diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index e39857ce6481..b36c145c498d 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -634,6 +634,14 @@ static void iommu_enable_command_buffer(struct amd_iommu *iommu)
amd_iommu_reset_cmd_buffer(iommu);
}

+/*
+ * This function disables the command buffer
+ */
+static void iommu_disable_command_buffer(struct amd_iommu *iommu)
+{
+ iommu_feature_disable(iommu, CONTROL_CMDBUF_EN);
+}
+
static void __init free_command_buffer(struct amd_iommu *iommu)
{
free_pages((unsigned long)iommu->cmd_buf, get_order(CMD_BUFFER_SIZE));
@@ -666,6 +674,14 @@ static void iommu_enable_event_buffer(struct amd_iommu *iommu)
iommu_feature_enable(iommu, CONTROL_EVT_LOG_EN);
}

+/*
+ * This function disables the event log buffer
+ */
+static void iommu_disable_event_buffer(struct amd_iommu *iommu)
+{
+ iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN);
+}
+
static void __init free_event_buffer(struct amd_iommu *iommu)
{
free_pages((unsigned long)iommu->evt_buf, get_order(EVT_BUFFER_SIZE));
@@ -2046,6 +2062,19 @@ static void iommu_enable_ga(struct amd_iommu *iommu)
#endif
}

+static void early_enable_iommu(struct amd_iommu *iommu)
+{
+ iommu_disable(iommu);
+ iommu_init_flags(iommu);
+ iommu_set_device_table(iommu);
+ iommu_enable_command_buffer(iommu);
+ iommu_enable_event_buffer(iommu);
+ iommu_set_exclusion_range(iommu);
+ iommu_enable_ga(iommu);
+ iommu_enable(iommu);
+ iommu_flush_all_caches(iommu);
+}
+
/*
* This function finally enables all IOMMUs found in the system after
* they have been initialized
@@ -2054,17 +2083,8 @@ static void early_enable_iommus(void)
{
struct amd_iommu *iommu;

- for_each_iommu(iommu) {
- iommu_disable(iommu);
- iommu_init_flags(iommu);
- iommu_set_device_table(iommu);
- iommu_enable_command_buffer(iommu);
- iommu_enable_event_buffer(iommu);
- iommu_set_exclusion_range(iommu);
- iommu_enable_ga(iommu);
- iommu_enable(iommu);
- iommu_flush_all_caches(iommu);
- }
+ for_each_iommu(iommu)
+ early_enable_iommu(iommu);

#ifdef CONFIG_IRQ_REMAP
if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
--
2.5.5