1 files changed, 31 insertions, 0 deletions

diff --git a/drivers/misc/cxl/native.c b/drivers/misc/cxl/native.c
index 387fcbdf9793..ecf7557cd657 100644
--- a/drivers/misc/cxl/native.c
+++ b/drivers/misc/cxl/native.c
@@ -14,6 +14,7 @@
 #include <linux/mutex.h>
 #include <linux/mm.h>
 #include <linux/uaccess.h>
+#include <linux/delay.h>
 #include <asm/synch.h>
 #include <misc/cxl-base.h>
 
@@ -797,6 +798,35 @@ static irqreturn_t native_irq_multiplexed(int irq, void *data)
         return fail_psl_irq(afu, &irq_info);
 }
 
+void native_irq_wait(struct cxl_context *ctx)
+{
+        u64 dsisr;
+        int timeout = 1000;
+        int ph;
+
+        /*
+         * Wait until no further interrupts are presented by the PSL
+         * for this context.
+         */
+        while (timeout--) {
+                ph = cxl_p2n_read(ctx->afu, CXL_PSL_PEHandle_An) & 0xffff;
+                if (ph != ctx->pe)
+                        return;
+                dsisr = cxl_p2n_read(ctx->afu, CXL_PSL_DSISR_An);
+                if ((dsisr & CXL_PSL_DSISR_PENDING) == 0)
+                        return;
+                /*
+                 * We are waiting for the workqueue to process our
+                 * irq, so need to let that run here.
+                 */
+                msleep(1);
+        }
+
+        dev_warn(&ctx->afu->dev, "WARNING: waiting on DSI for PE %i"
+                 " DSISR %016llx!\n", ph, dsisr);
+        return;
+}
+
 static irqreturn_t native_slice_irq_err(int irq, void *data)
 {
         struct cxl_afu *afu = data;
@@ -1076,6 +1106,7 @@ const struct cxl_backend_ops cxl_native_ops = {
         .handle_psl_slice_error = native_handle_psl_slice_error,
         .psl_interrupt = NULL,
         .ack_irq = native_ack_irq,
+        .irq_wait = native_irq_wait,
         .attach_process = native_attach_process,
         .detach_process = native_detach_process,
         .support_attributes = native_support_attributes,