From dc6e780a7a1222ad521e21bdf3832fa3e923b087 Mon Sep 17 00:00:00 2001
From: David Belanger <david.belanger@amd.com>
Date: Wed, 16 Feb 2022 12:07:28 -0500
Subject: drm/amdkfd: EOP Removal - Handle size 0 correctly
Git-commit: 1526ec9a3ed90e7ad36de7ef8aa2768b60af14df
Patch-mainline: v6.5-rc1
References: jsc#PED-3527 jsc#PED-5475 jsc#PED-6068 jsc#PED-6070 jsc#PED-6116 jsc#PED-6120 jsc#PED-5065 jsc#PED-5477 jsc#PED-5511 jsc#PED-6041 jsc#PED-6069 jsc#PED-6071
On GC 9.4.3, we are removing the EOP buffer.
If we specify 0 for the size, CP_HQD_EOP_CONTROL ends up with
incorrect value as order_size_2 calculations does not handle 0.
Fix it by using zero for the MQD entry for EOP size 0.
v2: Reworked code with a conditional assignment and fixed style issues.
Signed-off-by: David Belanger <david.belanger@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c b/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c
index 5c9b3392758e..2e2a0f8586f7 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c
@@ -257,9 +257,14 @@ static void update_mqd(struct mqd_manager *mm, void *mqd,
* Limit is 0xFF EOP entries (= 0x7F8 dwords). CP will not submit
* more than (EOP entry count - 1) so a queue size of 0x800 dwords
* is safe, giving a maximum field value of 0xA.
+ *
+ * Also, do calculation only if EOP is used (size > 0), otherwise
+ * the order_base_2 calculation provides incorrect result.
+ *
*/
- m->cp_hqd_eop_control = min(0xA,
- order_base_2(q->eop_ring_buffer_size / 4) - 1);
+ m->cp_hqd_eop_control = q->eop_ring_buffer_size ?
+ min(0xA, order_base_2(q->eop_ring_buffer_size / 4) - 1) : 0;
+
m->cp_hqd_eop_base_addr_lo =
lower_32_bits(q->eop_ring_buffer_address >> 8);
m->cp_hqd_eop_base_addr_hi =
--
2.42.0