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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?g1ULhwQopPePENxfTS/ENpFP5uzjBSdAwI5vj7mEbX06tzQ9HjCnjwG6D294?= =?us-ascii?Q?PXtO5z9soR/rphp9zyWMnTH79Eqsiwgmnw8xicnKiylGey+cm7IBotrhGcPF?= =?us-ascii?Q?/tKdnZozIVcmeJ1oPAySfCz3mLgBwM2ENgMPW7rD9NbQf6+TJmizuh3M2btr?= =?us-ascii?Q?pgjN4gp7b2EzqTbmw1c6FhAF8PLy9aGOHxuaW+3xNkIsd+HAp5bdtAyr7Z58?= =?us-ascii?Q?wBr5q2VEWt3L8dqQ/fVzE6a2qvqQEIsPpauJuXCqCkfqGQRiNaX7CWn6t2UR?= =?us-ascii?Q?s1jlyM8YU4zJxTsty/6qzC3u/uIntThKLt05G8EOkuLQtA7k1iCnOmoOTlc7?= =?us-ascii?Q?72eo4crpi4Tcs+mhpIBWy/tUoVx48sdWRtmKK53zYz0xlht+X0WC+LFc51qH?= =?us-ascii?Q?UYRKZMmhz85zx3IbbU0yzfDYjrx5jmEqkX2xA9sBjWJ4XvW8keESxYHufLDV?= =?us-ascii?Q?m6Og+xZ5bX5ue7I6opaCjC5ToZr9H3AiDiBpGkvd3UBete2gjWIbFax5mWgD?= =?us-ascii?Q?qJfnd4XqKa/tH24Sijynvhxlg9tUzl3XBVtkgW45Kfsfjn4AUZz+W9FdhxxR?= =?us-ascii?Q?LZM5i5ZQyFTCmDoDl9s9j8zwmIg9G4BSjYWjYd+ryTUbaMh3HeQ7/teRLr/K?= =?us-ascii?Q?E+cysFvOhSBmoOhferFNWmCOV1MA62TmKoDZh68q8Gy5De03lRlZT8BrZT5b?= =?us-ascii?Q?0BYxzbgIhEjcJrsVetViMPHxs5elyIMsESY8vqo6Rtr2vqIVBKmKvEIjHbqn?= =?us-ascii?Q?Qk5fscAIV2tCx41NKkuoWeyywadsQLcTI/L1Q4cCSJbUgFn+1hhefj0+j+xw?= =?us-ascii?Q?O1UiO2l376ZXge0kkGZYPJ4Xk2WkUooDBoE5oxr+iJ0qqXDwZnxv1QdkP5HS?= =?us-ascii?Q?eN66AcdJdgfxkSvz6p05aloW35y6v9Vn0r+7E8pV6WAiQYG3vfsJDQtEZsp1?= =?us-ascii?Q?won89URN7DJe5grRM7lqEjMLT5gNQxT1uXCZpzKmMeLGJyPnYdo2EMZP3y2I?= =?us-ascii?Q?jpgzZz6wINDFIJ7oAYrb8faDSsuCFcl/6fy/d6kHaEJ1/fDBZpTI4OXF8MbG?= =?us-ascii?Q?mNDWXDwu+pCbjTrZKRWKhrvan60NZLIyuVqVyVfC70xc01KA36CfFnVrObuz?= =?us-ascii?Q?bgudjJJS4HlCDTcDE2PZcMfBvkf5gtQ0KASXQ8Y/zFJzDjBZjbTRiIwPAA7r?= =?us-ascii?Q?8yKy9qZzykiGsEuxLO104XgekPzEM52U2XtX5XzO/tF3c/P8J5JJxZqPvsFu?= =?us-ascii?Q?5xxgQiWo34BchdISnHgJt87wc1nJJYE0nJGzOygmITJW7//pPf8zHX1KrVGS?= =?us-ascii?Q?5e81GdG/akKwckvHDYGtGxR/+ByVR6QWPb11djnH9bnCpwTMSFewA7mpYM7u?= =?us-ascii?Q?EjIjf8PMimkoDtDi+kbwq3kq2Rle1L2TR7R/8NWdeac21vF+tJTdkfwnj/an?= =?us-ascii?Q?KA+QkpKaLRBvlOgR+nccsje3T6libDAFWIx59Yy92f2DZt3RCY3RiejZQtVy?= =?us-ascii?Q?gXO28VsKT0Z9IMiDLW1bEcjIg7syYu2QNT2lurmYgnUUg7BCC/B2SCHeTBsZ?= =?us-ascii?Q?hwOV8VK6DifiqRPODj2Usp+XDx5KGMyGInHUDbd3fxXiIkQ2YtiSrznxTz2i?= =?us-ascii?Q?8XenUzfF1jH2tgVJr8h7Vho1ZsR6fnJUpYVVFoPQOyRt38+j96dHhhACbyGh?= =?us-ascii?Q?oPok9CxlTjuYvCDnDJSFW3n5T1dIxkliMUFL61NGYf2WnP2t?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ac81baf4-4f0f-44eb-7b76-08deb1a41c21 X-MS-Exchange-CrossTenant-AuthSource: MW4PR12MB7000.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 May 2026 10:32:33.8982 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: DgwpcwDMiUrezqyxmSYYBj+2lVJ9qWupT8oTivWAq0983QopL6e3xKP1Vx8FDEureVWAMTH0XCh8jJnUsDXo6Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB7179 When the fence list is empty, host1x_intr_update_hw_state() falls through to host1x_intr_disable_syncpt_intr() which does two MMIO writes to disable the syncpoint interrupt and clear its status. The ISR has already disabled and acked the interrupt before calling host1x_intr_handle_interrupt(), making these two writes redundant. Skip the update_hw_state() call if no fences remain. Measured Syncpoint wait latency (50000 samples): Average latency: 10.6 us -> 9.4 us 99.99 pct latency: 51.90 us -> 36.58 us Signed-off-by: Tanmay Patil --- drivers/gpu/host1x/intr.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/host1x/intr.c b/drivers/gpu/host1x/intr.c index f77a678949e9..723297250768 100644 --- a/drivers/gpu/host1x/intr.c +++ b/drivers/gpu/host1x/intr.c @@ -92,8 +92,12 @@ void host1x_intr_handle_interrupt(struct host1x *host, unsigned int id) host1x_fence_signal(fence); } - /* Re-enable interrupt if necessary */ - host1x_intr_update_hw_state(host, sp); + /* + * Re-enable interrupt if necessary. The ISR already disabled the interrupt, + * so if no fences remain, no update is needed. + */ + if (!list_empty(&sp->fences.list)) + host1x_intr_update_hw_state(host, sp); spin_unlock(&sp->fences.lock); } -- 2.54.0