iommu/mediatek: Move attach_device after iommu-group is ready for M4Uv1
In the commit
05f80300dc8b ("iommu: Finish making iommu_group support
mandatory"), the iommu framework has supposed all the iommu drivers have
their owner iommu-group, it get rid of the FIXME workarounds while the
group is NULL. But the flow of Mediatek M4U gen1 looks a bit trick that
it will hang at this case:
==========================================
Unable to handle kernel NULL pointer dereference at virtual address
00000030
pgd =
c0004000
[
00000030] *pgd=
00000000
PC is at mutex_lock+0x28/0x54
LR is at iommu_attach_device+0xa4/0xd4
pc : [<
c07632e8>] lr : [<
c04736fc>] psr:
60000013
sp :
df0edbb8 ip :
df0edbc8 fp :
df0edbc4
r10:
c114da14 r9 :
df2a3e40 r8 :
00000003
r7 :
df27a210 r6 :
df2a90c4 r5 :
00000030 r4 :
00000000
r3 :
df0f8000 r2 :
fffff000 r1 :
df29c610 r0 :
00000030
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
xxx
(mutex_lock) from [<
c04736fc>] (iommu_attach_device+0xa4/0xd4)
(iommu_attach_device) from [<
c011b9dc>] (__arm_iommu_attach_device+0x28/0x90)
(__arm_iommu_attach_device) from [<
c011ba60>] (arm_iommu_attach_device+0x1c/0x30)
(arm_iommu_attach_device) from [<
c04759ac>] (mtk_iommu_add_device+0xfc/0x214)
(mtk_iommu_add_device) from [<
c0472aa4>] (add_iommu_group+0x3c/0x68)
(add_iommu_group) from [<
c047d044>] (bus_for_each_dev+0x78/0xac)
(bus_for_each_dev) from [<
c04734a4>] (bus_set_iommu+0xb0/0xec)
(bus_set_iommu) from [<
c0476310>] (mtk_iommu_probe+0x328/0x368)
(mtk_iommu_probe) from [<
c048189c>] (platform_drv_probe+0x5c/0xc0)
(platform_drv_probe) from [<
c047f510>] (driver_probe_device+0x2f4/0x4d8)
(driver_probe_device) from [<
c047f800>] (__driver_attach+0x10c/0x128)
(__driver_attach) from [<
c047d044>] (bus_for_each_dev+0x78/0xac)
(bus_for_each_dev) from [<
c047ec78>] (driver_attach+0x2c/0x30)
(driver_attach) from [<
c047e640>] (bus_add_driver+0x1e0/0x278)
(bus_add_driver) from [<
c048052c>] (driver_register+0x88/0x108)
(driver_register) from [<
c04817ec>] (__platform_driver_register+0x50/0x58)
(__platform_driver_register) from [<
c0b31380>] (m4u_init+0x24/0x28)
(m4u_init) from [<
c0101c38>] (do_one_initcall+0xf0/0x17c)
=========================
The root cause is that the device's iommu-group is NULL while
arm_iommu_attach_device is called. This patch prepare a new iommu-group
for the iommu consumer devices to fix this issue.
CC: Robin Murphy <robin.murphy@arm.com>
CC: Honghui Zhang <honghui.zhang@mediatek.com>
Fixes: 05f80300dc8b ("iommu: Finish making iommu_group support mandatory")
Reported-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>