dma: cppi41: redo descriptor collection in abort case

Most of the logic here is try and error since what actually happens does
not match the trm or I miss read it.
My first assumption was that the queue on which the tear-down descriptor
completes (their own complete queue vs "active descriptor" complete
queue) depends on the transfer direction. This seems not to be true
because I manage to trigger
|  WARN_ON(c->desc_phys != desc_phys);
and the other few were fine means the tear-down descriptor was valid but
on different queue.

This patch changes the logic here to look on both queues for the
descriptor.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 16 insertions, 26 deletions

diff --git a/drivers/dma/cppi41.c b/drivers/dma/cppi41.c
index 2500f60393f4..ec87492cfb07 100644
--- a/drivers/dma/cppi41.c
+++ b/drivers/dma/cppi41.c
@@ -563,36 +563,26 @@ static int cppi41_tear_down_chan(struct cppi41_channel *c)
                 c->td_retry = 100;
         }
 
-        if (!c->td_seen) {
-                unsigned td_comp_queue;
+        if (!c->td_seen || !c->td_desc_seen) {
 
-                if (c->is_tx)
-                        td_comp_queue =  cdd->td_queue.complete;
-                else
-                        td_comp_queue =  c->q_comp_num;
+                desc_phys = cppi41_pop_desc(cdd, cdd->td_queue.complete);
+                if (!desc_phys)
+                        desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
 
-                desc_phys = cppi41_pop_desc(cdd, td_comp_queue);
-                if (desc_phys) {
-                        __iormb();
+                if (desc_phys == c->desc_phys) {
+                        c->td_desc_seen = 1;
+
+                } else if (desc_phys == td_desc_phys) {
+                        u32 pd0;
 
-                        if (desc_phys == td_desc_phys) {
-                                u32 pd0;
-                                pd0 = td->pd0;
-                                WARN_ON((pd0 >> DESC_TYPE) != DESC_TYPE_TEARD);
-                                WARN_ON(!c->is_tx && !(pd0 & TD_DESC_IS_RX));
-                                WARN_ON((pd0 & 0x1f) != c->port_num);
-                        } else {
-                                WARN_ON_ONCE(1);
-                        }
-                        c->td_seen = 1;
-                }
-        }
-        if (!c->td_desc_seen) {
-                desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
-                if (desc_phys) {
                         __iormb();
-                        WARN_ON(c->desc_phys != desc_phys);
-                        c->td_desc_seen = 1;
+                        pd0 = td->pd0;
+                        WARN_ON((pd0 >> DESC_TYPE) != DESC_TYPE_TEARD);
+                        WARN_ON(!c->is_tx && !(pd0 & TD_DESC_IS_RX));
+                        WARN_ON((pd0 & 0x1f) != c->port_num);
+                        c->td_seen = 1;
+                } else if (desc_phys) {
+                        WARN_ON_ONCE(1);
                 }
         }
         c->td_retry--;