linux-toradex.git/drivers/gpu/drm/ast, branch v4.4.93

drm/ast: Handle configuration without P2A bridge

2017-07-05T12:37:15+00:00

commit 71f677a91046599ece96ebab21df956ce909c456 upstream.

The ast driver configures a window to enable access into BMC
memory space in order to read some configuration registers.

If this window is disabled, which it can be from the BMC side,
the ast driver can't function.

Closing this window is a necessity for security if a machine's
host side and BMC side are controlled by different parties;
i.e. a cloud provider offering machines "bare metal".

A recent patch went in to try to check if that window is open
but it does so by trying to access the registers in question
and testing if the result is 0xffffffff.

This method will trigger a PCIe error when the window is closed
which on some systems will be fatal (it will trigger an EEH
for example on POWER which will take out the device).

This patch improves this in two ways:

 - First, if the firmware has put properties in the device-tree
containing the relevant configuration information, we use these.

 - Otherwise, a bit in one of the SCU scratch registers (which
are readable via the VGA register space and writeable by the BMC)
will indicate if the BMC has closed the window. This bit has been
defined by Y.C Chen from Aspeed.

If the window is closed and the configuration isn't available from
the device-tree, some sane defaults are used. Those defaults are
hopefully sufficient for standard video modes used on a server.

Signed-off-by: Russell Currey 
Acked-by: Joel Stanley 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Dave Airlie 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

drm/ast: Fixed system hanged if disable P2A

2017-06-17T04:39:38+00:00

[ Upstream commit 6c971c09f38704513c426ba6515f22fb3d6c87d5 ]

The original ast driver will access some BMC configuration through P2A bridge
that can be disabled since AST2300 and after.
It will cause system hanged if P2A bridge is disabled.
Here is the update to fix it.

Signed-off-by: Y.C. Chen 
Signed-off-by: Dave Airlie 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

drm/ast: Fix AST2400 POST failure without BMC FW or VBIOS

2017-03-15T01:57:14+00:00

commit 3856081eede297b617560b85e948cfb00bb395ec upstream.

The current POST code for the AST2300/2400 family doesn't work properly
if the chip hasn't been initialized previously by either the BMC own FW
or the VBIOS. This fixes it.

Signed-off-by: Y.C. Chen 
Signed-off-by: Benjamin Herrenschmidt 
Tested-by: Y.C. Chen 
Acked-by: Joel Stanley 
Signed-off-by: Dave Airlie 
Signed-off-by: Greg Kroah-Hartman

drm/ast: Call open_key before enable_mmio in POST code

2017-03-15T01:57:14+00:00

commit 9bb92f51558f2ef5f56c257bdcea0588f31d857e upstream.

open_key enables access the registers used by enable_mmio

Signed-off-by: Y.C. Chen 
Signed-off-by: Benjamin Herrenschmidt 
Acked-by: Joel Stanley 
Tested-by: Y.C. Chen 
Signed-off-by: Dave Airlie 
Signed-off-by: Greg Kroah-Hartman

drm/ast: Fix test for VGA enabled

2017-03-15T01:57:14+00:00

commit 905f21a49d388de3e99438235f3301cabf0c0ef4 upstream.

The test to see if VGA was already enabled is doing an unnecessary
second test from a register that may or may not have been initialized
to a valid value. Remove it.

Signed-off-by: Y.C. Chen 
Signed-off-by: Benjamin Herrenschmidt 
Acked-by: Joel Stanley 
Tested-by: Y.C. Chen 
Signed-off-by: Dave Airlie 
Signed-off-by: Greg Kroah-Hartman

drivers/gpu/drm/ast: Fix infinite loop if read fails

2017-01-09T07:07:46+00:00

commit 298360af3dab45659810fdc51aba0c9f4097e4f6 upstream.

ast_get_dram_info() configures a window in order to access BMC memory.
A BMC register can be configured to disallow this, and if so, causes
an infinite loop in the ast driver which renders the system unusable.

Fix this by erroring out if an error is detected.  On powerpc systems with
EEH, this leads to the device being fenced and the system continuing to
operate.

Signed-off-by: Russell Currey 
Reviewed-by: Joel Stanley 
Signed-off-by: Daniel Vetter 
Link: http://patchwork.freedesktop.org/patch/msgid/20161215051241.20815-1-ruscur@russell.cc
Signed-off-by: Greg Kroah-Hartman

drm/ast: Fix incorrect register check for DRAM width

2016-03-09T23:34:51+00:00

commit 2d02b8bdba322b527c5f5168ce1ca10c2d982a78 upstream.

During DRAM initialization on certain ASpeed devices, an incorrect
bit (bit 10) was checked in the "SDRAM Bus Width Status" register
to determine DRAM width.

Query bit 6 instead in accordance with the Aspeed AST2050 datasheet v1.05.

Signed-off-by: Timothy Pearson 
Signed-off-by: Dave Airlie 
Signed-off-by: Greg Kroah-Hartman

drm/ast: Initialized data needed to map fbdev memory

2015-11-11T02:27:31+00:00

Due to a missing initialization there was no way to map fbdev memory.
Thus for example using the Xserver with the fbdev driver failed.
This fix adds initialization for fix.smem_start and fix.smem_len
in the fb_info structure, which fixes this problem.

Requested-by: Benjamin Herrenschmidt 
Cc: stable@vger.kernel.org
Signed-off-by: Egbert Eich 
[pulled from SuSE tree by me - airlied]
Signed-off-by: Dave Airlie

drm/ast: Don't grab dev->struct_mutex for in mmap offset ioctl

2015-08-10T11:36:55+00:00

Since David Herrmann's mmap vma manager rework we don't need to grab
dev->struct_mutex any more to prevent races when looking up the mmap
offset. Drop it and instead don't forget to use the unref_unlocked
variant (since the drm core still cares).

Reviewed-by: Thierry Reding 
Signed-off-by: Daniel Vetter

drm/ast: Use new drm_fb_helper functions

2015-08-06T12:12:57+00:00

Use the newly created wrapper drm_fb_helper functions instead of calling
core fbdev functions directly. They also simplify the fb_info creation.

Cleaned up the error handling in astfb_create a bit.

v2:
- removed unused variable 'device' in astfb_create

Cc: David Airlie 
Cc: "Y.C. Chen" 
Cc: Alex Deucher 

Signed-off-by: Archit Taneja 
Signed-off-by: Daniel Vetter