[Intel-gfx] [PATCH 22/39] drm/i915/tgl: implement WaProgramMgsrForCorrectSliceSpecificMmioReads

[Lucas De Marchi]

>From my tests this workaround is needed otherwise we read the wrong
number of slices later on. It's sent as a FIXME since I couldn't find
any documentation saying this applies to TGL. Fix the following warning:

[   82.905527] WARN_ON_ONCE((mcr & mcr_slice_subslice_mask) != default_mcr_s_ss_
select)
[   82.905618] WARNING: CPU: 3 PID: 1118 at drivers/gpu/drm/i915/intel_engine_cs
.c:927 intel_engine_get_instdone+0x4c4/0x530 [i915]
[   82.905629] Modules linked in: i915
[   82.905642] CPU: 3 PID: 1118 Comm: cat Tainted: G     U  W         4.17.0-rc7
-demarchi+ #7
[   82.905653] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[   82.905711] RIP: 0010:intel_engine_get_instdone+0x4c4/0x530 [i915]
[   82.905722] RSP: 0018:ffffb5a381317be8 EFLAGS: 00010092
[   82.905734] RAX: 0000000000000048 RBX: 0000000008000000 RCX: ffffffff9165c748
[   82.905745] RDX: 0000000000000001 RSI: 0000000000000086 RDI: 0000000000000087
[   82.905756] RBP: 0000000000000001 R08: 297463656c65735f R09: 00000000000003c2
[   82.905768] R10: 5f746c7561666564 R11: 73735f735f72636d R12: 0000000000000000
[   82.905779] R13: 0000000000000000 R14: ffff98b598a00000 R15: 0000000000000000
[   82.905791] FS:  00007f6e6fa5e500(0000) GS:ffff98b5bfb80000(0000) knlGS:00000
00000000000
[   82.905802] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   82.905813] CR2: 00007f6e6fa3b000 CR3: 0000000232606000 CR4: 00000000000006e0
[   82.905824] Call Trace:
[   82.905883]  i915_hangcheck_info+0xf7/0x3d0 [i915]
[   82.905898]  seq_read+0x15b/0x440
[   82.905911]  ? __handle_mm_fault+0xaf9/0x1270
[   82.905923]  full_proxy_read+0x53/0x80
[   82.905936]  __vfs_read+0x26/0x140
[   82.905949]  vfs_read+0x8a/0x140
[   82.905961]  ksys_read+0x3f/0xa0
[   82.905974]  do_syscall_64+0x5b/0x160
[   82.905986]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   82.905998] RIP: 0033:0x7f6e6f585701
[   82.906009] RSP: 002b:00007ffff94652e8 EFLAGS: 00000246 ORIG_RAX: 00000000000

CC: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
---
 drivers/gpu/drm/i915/gt/intel_workarounds.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index b58e1e6e610f..a227a0272f3c 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -768,7 +768,7 @@ wa_init_mcr(struct drm_i915_private *i915, struct i915_wa_list *wal)
 	 * by default, to make sure we correctly read certain registers
 	 * later on (in the range 0xB100 - 0xB3FF).
 	 *
-	 * WaProgramMgsrForCorrectSliceSpecificMmioReads:cnl,icl
+	 * WaProgramMgsrForCorrectSliceSpecificMmioReads:cnl,icl,tgl
 	 * Before any MMIO read into slice/subslice specific registers, MCR
 	 * packet control register needs to be programmed to point to any
 	 * enabled s/ss pair. Otherwise, incorrect values will be returned.
@@ -900,6 +900,7 @@ icl_gt_workarounds_init(struct drm_i915_private *i915, struct i915_wa_list *wal)
 static void
 tgl_gt_workarounds_init(struct drm_i915_private *i915, struct i915_wa_list *wal)
 {
+	wa_init_mcr(i915, wal);
 }
 
 static void
-- 
2.21.0