[ Upstream commit 1262cc8893ecb0eb2c21e042d0d268cc180edb61 ]
During boot, I get this kernel warning:
WARNING: CPU: 0 PID: 19001 at kernel/dma/debug.c:1301 debug_dma_map_sg+0x284/0x3dc etnaviv etnaviv: DMA-API: mapping sg segment longer than device claims to support [len=3145728] [max=65536] Modules linked in: ip6t_REJECT nf_reject_ipv6 ip6t_rpfilter xt_tcpudp ipt_REJECT nf_reject_ipv4 xt_conntrack ip_set nfnetlink ebtable_broute ebtable_nat ip6table_raw ip6table_nat nf_nat_ipv6 ip6table_mangle iptable_raw iptable_nat nf_nat_ipv4 nf_nat nf_conntrack nf_defrag_ipv4 nf_defrag_ipv6 libcrc32c iptable_mangle ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter caam_jr error snd_soc_imx_spdif imx_thermal snd_soc_imx_audmux nvmem_imx_ocotp snd_soc_sgtl5000 caam imx_sdma virt_dma coda rc_cec v4l2_mem2mem snd_soc_fsl_ssi snd_soc_fsl_spdif imx_vdoa imx_pcm_dma videobuf2_dma_contig etnaviv dw_hdmi_cec gpu_sched dw_hdmi_ahb_audio imx6q_cpufreq nfsd sch_fq_codel ip_tables x_tables CPU: 0 PID: 19001 Comm: Xorg Not tainted 4.20.0+ #307 Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) [<c0019658>] (unwind_backtrace) from [<c001489c>] (show_stack+0x10/0x14) [<c001489c>] (show_stack) from [<c07fb420>] (dump_stack+0x9c/0xd4) [<c07fb420>] (dump_stack) from [<c00312dc>] (__warn+0xf8/0x124) [<c00312dc>] (__warn) from [<c00313d0>] (warn_slowpath_fmt+0x38/0x48) [<c00313d0>] (warn_slowpath_fmt) from [<c00b14e8>] (debug_dma_map_sg+0x284/0x3dc) [<c00b14e8>] (debug_dma_map_sg) from [<c046eb40>] (drm_gem_map_dma_buf+0xc4/0x13c) [<c046eb40>] (drm_gem_map_dma_buf) from [<c04c3314>] (dma_buf_map_attachment+0x38/0x5c) [<c04c3314>] (dma_buf_map_attachment) from [<c046e728>] (drm_gem_prime_import_dev+0x74/0x104) [<c046e728>] (drm_gem_prime_import_dev) from [<c046e5bc>] (drm_gem_prime_fd_to_handle+0x84/0x17c) [<c046e5bc>] (drm_gem_prime_fd_to_handle) from [<c046edd0>] (drm_prime_fd_to_handle_ioctl+0x38/0x4c) [<c046edd0>] (drm_prime_fd_to_handle_ioctl) from [<c0460efc>] (drm_ioctl_kernel+0x90/0xc8) [<c0460efc>] (drm_ioctl_kernel) from [<c0461114>] (drm_ioctl+0x1e0/0x3b0) [<c0461114>] (drm_ioctl) from [<c01cae20>] (do_vfs_ioctl+0x90/0xa48) [<c01cae20>] (do_vfs_ioctl) from [<c01cb80c>] (ksys_ioctl+0x34/0x60) [<c01cb80c>] (ksys_ioctl) from [<c0009000>] (ret_fast_syscall+0x0/0x28) Exception stack(0xd81a9fa8 to 0xd81a9ff0) 9fa0: b6c69c88 bec613f8 00000009 c00c642e bec613f8 b86c4600 9fc0: b6c69c88 bec613f8 c00c642e 00000036 012762e0 01276348 00000300 012d91f8 9fe0: b6989f18 bec613dc b697185c b667be5c irq event stamp: 47905 hardirqs last enabled at (47913): [<c0098824>] console_unlock+0x46c/0x680 hardirqs last disabled at (47922): [<c0098470>] console_unlock+0xb8/0x680 softirqs last enabled at (47754): [<c000a484>] __do_softirq+0x344/0x540 softirqs last disabled at (47701): [<c0038700>] irq_exit+0x124/0x144 ---[ end trace af477747acbcc642 ]---
The reason is the contiguous buffer exceeds the default maximum segment size of 64K as specified by dma_get_max_seg_size() in linux/dma-mapping.h. Fix this by providing our own segment size, which is set to 2GiB to cover the window found in MMUv1 GPUs.
Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: Lucas Stach l.stach@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/etnaviv/etnaviv_drv.c | 5 +++++ drivers/gpu/drm/etnaviv/etnaviv_drv.h | 1 + 2 files changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c index 18c27f795cf61..3156450723bad 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c @@ -515,6 +515,9 @@ static int etnaviv_bind(struct device *dev) } drm->dev_private = priv;
+ dev->dma_parms = &priv->dma_parms; + dma_set_max_seg_size(dev, SZ_2G); + mutex_init(&priv->gem_lock); INIT_LIST_HEAD(&priv->gem_list); priv->num_gpus = 0; @@ -552,6 +555,8 @@ static void etnaviv_unbind(struct device *dev)
component_unbind_all(dev, drm);
+ dev->dma_parms = NULL; + drm->dev_private = NULL; kfree(priv);
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.h b/drivers/gpu/drm/etnaviv/etnaviv_drv.h index 4bf698de59969..51b7bdf5748bc 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.h +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.h @@ -43,6 +43,7 @@ struct etnaviv_file_private {
struct etnaviv_drm_private { int num_gpus; + struct device_dma_parameters dma_parms; struct etnaviv_gpu *gpu[ETNA_MAX_PIPES];
/* list of GEM objects: */