v2:
- function xe_device_is_vf_enabled has been refactored to
xe_sriov_pf_has_vfs_enabled and moved to xe_sriov_pf_helper.h.
- The code now distinctly checks for SR-IOV VF mode and
SR-IOV PF with VFs enabled.
- Log messages have been updated to explicitly state the current mode.
- The function xe_multi_ccs_mode_enabled is moved to xe_device.h
v3: Described missed arg documentation for xe_sriov_pf_has_vfs_enabled
v4:
- sysfs interface for CCS mode is not initialized
when operating in SRIOV VF Mode.
- xe_sriov_pf_has_vfs_enabled() check is sufficient while CCS mode
enablement.
- remove unnecessary comments as flow is self explanatory.
v5:(review comments from Michal)
- Add xe device level CCS mode block with mutex lock and CCS mode state
- necessesary functions to manage ccs mode state to provide strict mutual
exclusive support b/w CCS mode & SRIOV VF enabling
v6:
- Re modeled implementation based on lockdown the PF using custom guard
supported functions by Michal
Signed-off-by: Nareshkumar Gollakoti <[email protected]>
---
drivers/gpu/drm/xe/xe_gt_ccs_mode.c | 47 ++++++++++++++++++++++++-----
1 file changed, 39 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_gt_ccs_mode.c
b/drivers/gpu/drm/xe/xe_gt_ccs_mode.c
index 50fffc9ebf62..495bf517a6d3 100644
--- a/drivers/gpu/drm/xe/xe_gt_ccs_mode.c
+++ b/drivers/gpu/drm/xe/xe_gt_ccs_mode.c
@@ -13,6 +13,7 @@
#include "xe_gt_sysfs.h"
#include "xe_mmio.h"
#include "xe_sriov.h"
+#include "xe_sriov_pf_helpers.h"
static void __xe_gt_apply_ccs_mode(struct xe_gt *gt, u32 num_engines)
{
@@ -108,6 +109,30 @@ ccs_mode_show(struct device *kdev,
return sysfs_emit(buf, "%u\n", gt->ccs_mode);
}
+static int xe_gt_prepare_ccs_mode_enabling(struct xe_device *xe,
+ struct xe_gt *gt)
+{
+ /*
+ * The arm guard is only activated during CCS mode enabling,
+ * and this shuould happen when CCS mode is in default mode.
+ * lockdown arm guard ensures there is no VFS enabling
+ * as CCS mode enabling in progress/enabled.
+ */
+ if (!(gt->ccs_mode > 1))
+ return xe_sriov_pf_arm_guard(xe,
&xe->sriov.pf.guard_vfs_enabling,
+ true, NULL);
+ return 0;
+}
+
+static void xe_gt_finish_ccs_mode_enabling(struct xe_device *xe,
+ struct xe_gt *gt)
+{
+ /* disarm the guard, if CCS mode is reverted to default */
+ if (!(gt->ccs_mode > 1))
+ xe_sriov_pf_disarm_guard(xe, &xe->sriov.pf.guard_vfs_enabling,
+ true, NULL);
+}
+
static ssize_t
ccs_mode_store(struct device *kdev, struct device_attribute *attr,
const char *buff, size_t count)
@@ -117,15 +142,13 @@ ccs_mode_store(struct device *kdev, struct
device_attribute *attr,
u32 num_engines, num_slices;
int ret;
- if (IS_SRIOV(xe)) {
- xe_gt_dbg(gt, "Can't change compute mode when running as %s\n",
- xe_sriov_mode_to_string(xe_device_sriov_mode(xe)));
- return -EOPNOTSUPP;
- }
+ ret = xe_gt_prepare_ccs_mode_enabling(xe, gt);
+ if (ret)
+ return ret;
ret = kstrtou32(buff, 0, &num_engines);
if (ret)
- return ret;
+ goto err;
/*
* Ensure number of engines specified is valid and there is an
@@ -135,7 +158,8 @@ ccs_mode_store(struct device *kdev, struct device_attribute
*attr,
if (!num_engines || num_engines > num_slices || num_slices %
num_engines) {
xe_gt_dbg(gt, "Invalid compute config, %d engines %d slices\n",
num_engines, num_slices);
- return -EINVAL;
+ ret = -EINVAL;
+ goto err;
}
/* CCS mode can only be updated when there are no drm clients */
@@ -143,7 +167,8 @@ ccs_mode_store(struct device *kdev, struct device_attribute
*attr,
if (!list_empty(&xe->drm.filelist)) {
mutex_unlock(&xe->drm.filelist_mutex);
xe_gt_dbg(gt, "Rejecting compute mode change as there are active drm
clients\n");
- return -EBUSY;
+ ret = -EBUSY;
+ goto err;
}
if (gt->ccs_mode != num_engines) {
@@ -155,7 +180,13 @@ ccs_mode_store(struct device *kdev, struct
device_attribute *attr,
mutex_unlock(&xe->drm.filelist_mutex);
+ xe_gt_finish_ccs_mode_enabling(xe, gt);
+
return count;
+err:
+ xe_gt_finish_ccs_mode_enabling(xe, gt);
+
+ return ret;
}
static DEVICE_ATTR_RW(ccs_mode);
--
2.43.0
