[PATCH] drm/msm: Set dma maximum segment size for mdss

[Stephen Boyd]

Quoting Sean Paul (2018-11-06 13:32:32)
> From: Sean Paul <seanpaul at chromium.org>
> 
> Turning on CONFIG_DMA_API_DEBUG_SG results in the following error:
> 
> [   12.078665] msm ae00000.mdss: DMA-API: mapping sg segment longer than device claims to support [len=3526656] [max=65536]
> [   12.089870] WARNING: CPU: 6 PID: 334 at /mnt/host/source/src/third_party/kernel/v4.19/kernel/dma/debug.c:1301 debug_dma_map_sg+0x1dc/0x318
> [   12.102655] Modules linked in: joydev
> [   12.106442] CPU: 6 PID: 334 Comm: frecon Not tainted 4.19.0 #2
> [   12.112450] Hardware name: Google Cheza (rev3+) (DT)
> [   12.117566] pstate: 60400009 (nZCv daif +PAN -UAO)
> [   12.122506] pc : debug_dma_map_sg+0x1dc/0x318
> [   12.126995] lr : debug_dma_map_sg+0x1dc/0x318
> [   12.131487] sp : ffffff800cc3ba80
> [   12.134913] x29: ffffff800cc3ba80 x28: 0000000000000000
> [   12.140395] x27: 0000000000000004 x26: 0000000000000004
> [   12.145868] x25: ffffff8008e55b18 x24: 0000000000000000
> [   12.151337] x23: 00000000ffffffff x22: ffffff800921c000
> [   12.156809] x21: ffffffc0fa75b080 x20: ffffffc0f7195090
> [   12.162280] x19: ffffffc0f1c53280 x18: 0000000000000000
> [   12.167749] x17: 0000000000000000 x16: 0000000000000000
> [   12.173218] x15: 0000000000000000 x14: 0720072007200720
> [   12.178689] x13: 0720072007200720 x12: 0720072007200720
> [   12.184161] x11: 0720072007200720 x10: 0720072007200720
> [   12.189641] x9 : ffffffc0f1fc6b60 x8 : 0000000000000000
> [   12.195110] x7 : ffffff8008132ce0 x6 : 0000000000000000
> [   12.200585] x5 : 0000000000000000 x4 : ffffff8008134734
> [   12.206058] x3 : ffffff800cc3b830 x2 : ffffffc0f1fc6240
> [   12.211532] x1 : 25045a74f48a7400 x0 : 25045a74f48a7400
> [   12.217006] Call trace:
> [   12.219535]  debug_dma_map_sg+0x1dc/0x318
> [   12.223671]  get_pages+0x19c/0x20c
> [   12.227177]  msm_gem_fault+0x64/0xfc
> [   12.230874]  __do_fault+0x3c/0x140
> [   12.234383]  __handle_mm_fault+0x70c/0xdb8
> [   12.238603]  handle_mm_fault+0xac/0xc4
> [   12.242473]  do_page_fault+0x1bc/0x3d4
> [   12.246342]  do_translation_fault+0x54/0x88
> [   12.250652]  do_mem_abort+0x60/0xf0
> [   12.254250]  el0_da+0x20/0x24
> [   12.257317] irq event stamp: 67260
> [   12.260828] hardirqs last  enabled at (67259): [<ffffff8008132d0c>] console_unlock+0x214/0x608
> [   12.269693] hardirqs last disabled at (67260): [<ffffff8008080e0c>] do_debug_exception+0x5c/0x178
> [   12.278820] softirqs last  enabled at (67256): [<ffffff8008081664>] __do_softirq+0x4d4/0x520
> [   12.287510] softirqs last disabled at (67249): [<ffffff80080be574>] irq_exit+0xa8/0x100
> [   12.295742] ---[ end trace e63cfc40c313ffab ]---

Tested-by: Stephen Boyd <swboyd at chromium.org>