From 0a36ef3c588659af5e0ec4ed646b2bae222912f0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Adri=C3=A1n=20Larumbe?= Date: Tue, 9 Jul 2024 13:15:12 +0100 Subject: [PATCH] drm/panthor: flush FW AS caches in slow reset path MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In the off-chance that waiting for the firmware to signal its booted status timed out in the fast reset path, one must flush the cache lines for the entire FW VM address space before reloading the regions, otherwise stale values eventually lead to a scheduler job timeout. Signed-off-by: Adrián Larumbe --- drivers/gpu/drm/panthor/panthor_fw.c | 8 +++++++- drivers/gpu/drm/panthor/panthor_mmu.c | 19 ++++++++++++++++--- drivers/gpu/drm/panthor/panthor_mmu.h | 1 + 3 files changed, 24 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/panthor/panthor_fw.c b/drivers/gpu/drm/panthor/panthor_fw.c index 857f3f11258aa..ef232c0c20493 100644 --- a/drivers/gpu/drm/panthor/panthor_fw.c +++ b/drivers/gpu/drm/panthor/panthor_fw.c @@ -1089,6 +1089,12 @@ int panthor_fw_post_reset(struct panthor_device *ptdev) panthor_fw_stop(ptdev); ptdev->fw->fast_reset = false; drm_err(&ptdev->base, "FW fast reset failed, trying a slow reset"); + + ret = panthor_vm_flush_all(ptdev->fw->vm); + if (ret) { + drm_err(&ptdev->base, "FW slow reset failed (couldn't flush FW's AS l2cache)"); + return ret; + } } /* Reload all sections, including RO ones. We're not supposed @@ -1099,7 +1105,7 @@ int panthor_fw_post_reset(struct panthor_device *ptdev) ret = panthor_fw_start(ptdev); if (ret) { - drm_err(&ptdev->base, "FW slow reset failed"); + drm_err(&ptdev->base, "FW slow reset failed (couldn't start the FW )"); return ret; } diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c index 15be29ff46c39..4f0f9cf6426b6 100644 --- a/drivers/gpu/drm/panthor/panthor_mmu.c +++ b/drivers/gpu/drm/panthor/panthor_mmu.c @@ -873,14 +873,27 @@ static int panthor_vm_flush_range(struct panthor_vm *vm, u64 iova, u64 size) if (!drm_dev_enter(&ptdev->base, &cookie)) return 0; - /* Flush the PTs only if we're already awake */ - if (pm_runtime_active(ptdev->base.dev)) - ret = mmu_hw_do_operation(vm, iova, size, AS_COMMAND_FLUSH_PT); + /* + * If we made it this far, that means the device is awake, because + * upon device suspension, all active VMs are given an AS id of -1 + */ + ret = mmu_hw_do_operation(vm, iova, size, AS_COMMAND_FLUSH_PT); drm_dev_exit(cookie); return ret; } +/** + * panthor_vm_flush_all() - Flush L2 caches for the entirety of a VM's AS + * @vm: VM whose cache to flush + * + * Return: 0 on success, a negative error code if flush failed. + */ +int panthor_vm_flush_all(struct panthor_vm *vm) +{ + return panthor_vm_flush_range(vm, vm->base.mm_start, vm->base.mm_range); +} + static int panthor_vm_unmap_pages(struct panthor_vm *vm, u64 iova, u64 size) { struct panthor_device *ptdev = vm->ptdev; diff --git a/drivers/gpu/drm/panthor/panthor_mmu.h b/drivers/gpu/drm/panthor/panthor_mmu.h index e6a2198b009b7..10635cc8a94df 100644 --- a/drivers/gpu/drm/panthor/panthor_mmu.h +++ b/drivers/gpu/drm/panthor/panthor_mmu.h @@ -31,6 +31,7 @@ panthor_vm_get_bo_for_va(struct panthor_vm *vm, u64 va, u64 *bo_offset); int panthor_vm_active(struct panthor_vm *vm); void panthor_vm_idle(struct panthor_vm *vm); int panthor_vm_as(struct panthor_vm *vm); +int panthor_vm_flush_all(struct panthor_vm *vm); struct panthor_heap_pool * panthor_vm_get_heap_pool(struct panthor_vm *vm, bool create);