linux-stable.git/drivers/crypto/caam/ctrl.c, branch v4.7.2

remove lots of IS_ERR_VALUE abuses

2016-05-27T22:26:11+00:00

Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.

However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.

Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.

This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.

Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err < 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.

I was using this definition for testing:

 #define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL && \
       unlikely((unsigned long long)(x) >= (unsigned long long)(typeof(x))-MAX_ERRNO))

which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.

I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.

[ Updated the 9p parts as per Al Viro  - Linus ]

Signed-off-by: Arnd Bergmann 
Cc: Andrzej Hajda 
Cc: Andrew Morton 
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla  # For nvmem part
Signed-off-by: Linus Torvalds

crypto: caam - enable LARGE_BURST for enhancing DMA transactions size

2016-01-25T14:39:03+00:00

Increasing CAAM DMA engine transaction size either
-reduces the number of required transactions or
-adds the ability to transfer more data with same transaction count

Signed-off-by: Horia Geant? 
Signed-off-by: Herbert Xu

crypto: caam - make write transactions bufferable on PPC platforms

2016-01-25T13:47:44+00:00

Previous change (see "Fixes" tag) to the MCFGR register
clears AWCACHE[0] ("bufferable" AXI3 attribute) (which is "1" at POR).

This makes all writes non-bufferable, causing a ~ 5% performance drop
for PPC-based platforms.

Rework previous change such that MCFGR[AWCACHE]=4'b0011
(bufferable + cacheable) for all platforms.
Note: For ARM-based platforms, AWCACHE[0] is ignored
by the interconnect IP.

Cc:  # 4.3+
Fixes: f10967495144 ("crypto: caam - fix snooping for write transactions")
Signed-off-by: Horia Geant? 
Signed-off-by: Herbert Xu

crypto: caam - Use the preferred style for memory allocations

2015-08-24T14:07:42+00:00

"The preferred form for passing a size of a struct is the following:

        p = kmalloc(sizeof(*p), ...);
....

The preferred form for allocating a zeroed array is the following:

        p = kcalloc(n, sizeof(...), ...); "

,so do as suggested.

Signed-off-by: Fabio Estevam 
Reviewed-by: Horia Geant? 
Signed-off-by: Herbert Xu

crypto: caam - Propagate the real error code in caam_probe

2015-08-24T14:07:41+00:00

Instead of propagating a 'fake' error code, just propagate the real
one in the case of caam_drv_identify_clk() failure.

Signed-off-by: Fabio Estevam 
Reviewed-by: Horia Geant? 
Signed-off-by: Herbert Xu

crypto: caam - Fix the error handling in caam_probe

2015-08-24T14:07:39+00:00

In the error path we should disable the resources that were previously
acquired, so fix the error handling accordingly.

Signed-off-by: Fabio Estevam 
Reviewed-by: Horia Geant? 
Signed-off-by: Herbert Xu

crypto: caam - fix writing to JQCR_MS when using service interface

2015-08-24T14:07:38+00:00

Most significant part of JQCR (Job Queue Control Register) contains
bits that control endianness: ILE - Immediate Little Endian,
DWS - Double Word Swap.
The bits are automatically set by the Job Queue Controller HW.

Unfortunately these bits are cleared in SW when submitting descriptors
via the register-based service interface.
>From LS1021A:
JQCR_MS = 08080100 - before writing: ILE | DWS | SRC (JR0)
JQCR_MS = 30000100 - after writing: WHL | FOUR | SRC (JR0)

This would cause problems on little endian caam for descriptors
containing immediata data or double-word pointers.
Currently there is no problem since the only descriptors ran through
this interface are the ones that (un)instantiate RNG.

Signed-off-by: Horia Geant? 
Signed-off-by: Herbert Xu

crypto: caam - add support for LS1021A

2015-08-18T02:30:39+00:00

LS1021A is a QorIQ SoC having little endian CAAM.

There are a few differences b/w QorIQ and i.MX from CAAM perspective:

1. i.MX platforms are somewhat special wrt. 64-bit registers:
-big endian format at 64-bit level: MSW at address+0 and LSW at address+4
-little endian format at 32-bit level (within MSW and LSW)
and thus need special handling.

2. No CCM (clock controller module) for QorIQ.
No CAAM clocks to enable / disable.

A new Kconfig option - CRYPTO_DEV_FSL_CAAM_LE - is added to indicate
CAAM is little endian (*). It is hidden from the user (to avoid
misconfiguration); when adding support for a new platform with LE CAAM,
either the Kconfig needs to be updated or the corresponding defconfig
needs to indicate that CAAM is LE.
(*) Using a DT property to provide CAAM endianness would not allow
for the ifdeffery.

In order to keep changes to a minimum, the following changes
are postponed:
-endianness fix of the last word in the S/G (rsvd2, bpid, offset),
fields are always 0 anyway;
-S/G format fix for i.MX7 (yes, i.MX7 support was not added yet,
but still...)

Signed-off-by: Horia Geant? 
Signed-off-by: Herbert Xu

crypto: caam - Remove unneeded 'ret' variable

2015-08-13T07:13:29+00:00

Variable 'ret' is only used for returning the value 0.

We can make it simpler and just return 0 instead.

The semantic patch that makes this change is available
in scripts/coccinelle/misc/returnvar.cocci.

Signed-off-by: Fabio Estevam 
Signed-off-by: Herbert Xu

crypto: caam - Enable and disable clocks on Freescale i.MX platforms

2015-08-10T15:18:56+00:00

ARM-based systems may disable clocking to the CAAM device on the
Freescale i.MX platform for power management purposes.  This patch
enables the required clocks when the CAAM module is initialized and
disables the required clocks when the CAAM module is shut down.

Signed-off-by: Victoria Milhoan 
Tested-by: Horia Geantă 
Signed-off-by: Herbert Xu