diff mbox series

[v9,14/22] macintosh/via-cuda: Don't rely on Cuda to end a transfer

Message ID 7c2b0db81b7778a4f90b007a968d1af09b1a63bf.1547525936.git.fthain@telegraphics.com.au (mailing list archive)
State Deferred, archived
Headers show
Series Re-use nvram module | expand

Checks

Context Check Description
snowpatch_ozlabs/apply_patch warning next/apply_patch Patch failed to apply
snowpatch_ozlabs/apply_patch fail Failed to apply to any branch

Commit Message

Finn Thain Jan. 15, 2019, 4:18 a.m. UTC 
Certain Cuda transfers have to be ended by the driver. According
to Apple's open source Cuda driver, as found in mkLinux and XNU, this
applies to any "open ended request such as PRAM read". This fixes an
infinite polling loop in cuda_pram_read_byte().

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
---
 drivers/macintosh/via-cuda.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/macintosh/via-cuda.c b/drivers/macintosh/via-cuda.c
index bbec6ac0a966..3581abfb0c6a 100644
--- a/drivers/macintosh/via-cuda.c
+++ b/drivers/macintosh/via-cuda.c
@@ -569,6 +569,7 @@  cuda_interrupt(int irq, void *arg)
     unsigned char ibuf[16];
     int ibuf_len = 0;
     int complete = 0;
+    bool full;
     
     spin_lock_irqsave(&cuda_lock, flags);
 
@@ -656,12 +657,13 @@  cuda_interrupt(int irq, void *arg)
 	break;
 
     case reading:
-	if (reading_reply ? ARRAY_FULL(current_req->reply, reply_ptr)
-	                  : ARRAY_FULL(cuda_rbuf, reply_ptr))
+	full = reading_reply ? ARRAY_FULL(current_req->reply, reply_ptr)
+	                     : ARRAY_FULL(cuda_rbuf, reply_ptr);
+	if (full)
 	    (void)in_8(&via[SR]);
 	else
 	    *reply_ptr++ = in_8(&via[SR]);
-	if (!TREQ_asserted(status)) {
+	if (!TREQ_asserted(status) || full) {
 	    if (mcu_is_egret)
 		assert_TACK();
 	    /* that's all folks */