Commit Graph

20 Commits

Author SHA1 Message Date
Vladimir Zapolskiy d449d69d21 misc: sram: fix check of devm_ioremap*() return value
Both devm_ioremap() and devm_ioremap_wc() functions return either
a pointer to valid iomem region or NULL, check for IS_ERR() is improper
and may result in oops on error path. Now on error -ENOMEM is returned.

Fixes: 0ab163ad1e ("misc: sram: switch to ioremap_wc from ioremap")
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 14:15:56 -07:00
Marcin Wojtas eb43e02313 misc: sram: add optional ioremap without write combining
Some SRAM users may require non-bufferable access to the memory, which is
impossible, because devm_ioremap_wc() is used for setting sram->virt_base.

This commit adds optional flag 'no-memory-wc', which allow to choose remap
method, using DT property. Documentation is updated accordingly.

Signed-off-by: Marcin Wojtas <mw@semihalf.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14 12:19:45 -04:00
Vladimir Zapolskiy 525d12f27b misc: sram: partition base address belongs to __iomem space
The change fixes a warning found by sparse:

  drivers/misc/sram.c:134:20: warning: incorrect type in assignment (different address spaces)
  drivers/misc/sram.c:134:20:    expected void *base
  drivers/misc/sram.c:134:20:    got void [noderef] <asn:2>*

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18 19:00:36 -07:00
Vladimir Zapolskiy b4c3fcb3c7 misc: sram: extend usage of reserved partitions
This change adds functionality to operate on reserved SRAM partitions
described in device tree file. Two partition properties are added,
"pool" and "export", the first one allows to share a specific partition
for usage by a kernel consumer in the same manner as it is done for
the whole SRAM device, and "export" property provides access to some
SRAM area from userspace over sysfs interface. Practically it is
possible to specify both properties for an SRAM partition, however
simultaneous access from a kernel consumer and from userspace is not
serialized, but still the combination may be useful for debugging
purpose.

The change opens the following scenarios of SRAM usage:
* updates in a particular SRAM area specified by offset and size are
  done by bootloader, then this information is utilized by the kernel,
* a particular SRAM area is rw accessed from userspace, the stored
  data is persistent on soft reboots,
* a device driver secures SRAM area for its purposes,
* etc.

Note, strictly speaking the added optional properties describe policy
of SRAM usage, rather than hardware, but here the policy mostly
resembles flash partitions in devicetree, which is undoubtedly
a very popular option but it does not describe hardware.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:51:47 -07:00
Vladimir Zapolskiy 7385817359 genalloc: add name arg to gen_pool_get() and devm_gen_pool_create()
This change modifies gen_pool_get() and devm_gen_pool_create() client
interfaces adding one more argument "name" of a gen_pool object.

Due to implementation gen_pool_get() is capable to retrieve only one
gen_pool associated with a device even if multiple gen_pools are created,
fortunately right at the moment it is sufficient for the clients, hence
provide NULL as a valid argument on both producer devm_gen_pool_create()
and consumer gen_pool_get() sides.

Because only one created gen_pool per device is addressable, explicitly
add a restriction to devm_gen_pool_create() to create only one gen_pool
per device, this implies two possible error codes returned by the
function, account it on client side (only misc/sram).  This completes
client side changes related to genalloc updates.

[akpm@linux-foundation.org: gen_pool_get() cleanup]
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Vladimir Zapolskiy 98ce2d27a3 misc: sram: sort and clean up included headers
Most of the included header files are already included as
dependencies.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12 17:03:57 -07:00
Vladimir Zapolskiy a0a5be0b36 misc: sram: move reserved block logic out of probe function
No functional change, but now previously overloaded sram_probe() is
greatly simplified and perceptible, reserved regions logic also has
its own space.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12 17:03:56 -07:00
Vladimir Zapolskiy 665d82fbbc misc: sram: add private struct device and virt_base members
No functional change, this is a preceding change to simplify
separation of reserved partition handling logic from probe()
function.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12 17:03:56 -07:00
Vladimir Zapolskiy 4914f1c717 misc: sram: report correct SRAM pool size
Since some space in SRAM may be reserved, report the left free space
in the allocated memory pool instead of total physical size of the
SRAM device.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12 17:03:56 -07:00
Vladimir Zapolskiy d687b1fa67 misc: sram: bump error message level on unclean driver unbinding
Report an error level message to a user, if the driver is unbound
while there are still some pool allocations.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12 17:03:56 -07:00
Vladimir Zapolskiy b13365bbec misc: sram: fix device node reference leak on error
A pointer device node reference should be decremented on manual exit
from for_each_available_child_of_node() loop.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12 17:03:56 -07:00
Vladimir Zapolskiy ee895ccdf7 misc: sram: fix enabled clock leak on error path
If devm_gen_pool_create() fails, the previously enabled sram->clk is
not disabled on probe() exit.

Because reserved block logic relies only on information from device tree,
there is no need to get and enable device clock in advance, especially
because not provided clock is not considered as an error, so it is
safe to place devm_clk_get() at the end of probe(). No functional
change.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12 17:03:56 -07:00
Abhilash Kesavan 0ab163ad1e misc: sram: switch to ioremap_wc from ioremap
Currently, the SRAM allocator returns device memory via ioremap.
This causes issues on ARM64 when the internal SoC SRAM allocated by
the generic sram driver is used for audio playback. The destination
buffer address (which is ioremapped SRAM) is not 64-bit aligned for
certain streams (e.g. 44.1k sampling rate). In such cases we get
unhandled alignment faults. Use ioremap_wc in place of ioremap which
gives us normal non-cacheable memory instead of device memory.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-16 21:11:32 +01:00
Fabian Frederick 6893d9b510 misc: constify of_device_id array
of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-16 21:10:28 +01:00
Heiko Stübner 2da19688f4 misc: sram: implement reserved sram areas
This implements support for defining reserved areas as subnodes,
to keep the genpool from using these.

Suggested-by: Rob Herring <robherring2@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Ulrich Prinz <ulrich.prinz@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-28 15:31:11 -08:00
Xiubo Li 590eca1e9f misc: sram: cleanup the code
Since the devm_gen_pool_create() is used, so the gen_pool_destroy()
here is redundant.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-07 15:10:19 -08:00
Heiko Stübner 5f90b9b484 misc: sram: fix error path in sram_probe
The pool is created thru devm_gen_pool_create, so the call to
gen_pool_destroy is not necessary.
Instead the sram-clock must be turned off again if it exists.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Ulrich Prinz <ulrich.prinz@googlemail.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-24 22:54:50 -07:00
Alexander Shiyan f3cbfa5d6e Misc: sram: Remove unneeded check
Patch removes unneeded check for resource since
devm_ioremap_resource do all for us.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17 16:41:49 -07:00
Laurent Navet 21b066f19a drivers: misc: use devm_ioremap_resource()
Replace a call to deprecated devm_request_and_ioremap by devm_ioremap_resource.

Found with coccicheck and this semantic patch:
 scripts/coccinelle/api/devm_request_and_ioremap.cocci.

Signed-off-by: Laurent Navet <laurent.navet@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-16 18:11:13 -07:00
Philipp Zabel 4984c6f5e5 misc: generic on-chip SRAM allocation driver
This driver requests and remaps a memory region as configured in the
device tree.  It serves memory from this region via the genalloc API.  It
optionally enables the SRAM clock.

Other drivers can retrieve the genalloc pool from a phandle pointing to
this drivers' device node in the device tree.

The allocation granularity is hard-coded to 32 bytes for now, to make the
SRAM driver useful for the 6502 remoteproc driver.  There is overhead for
bigger SRAMs, where only a much coarser allocation granularity is needed:
At 32 bytes minimum allocation size, a 256 KiB SRAM needs a 1 KiB bitmap
to track allocations.

[akpm@linux-foundation.org: fix Kconfig text, make sram_init static]
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Michal Simek <monstr@monstr.eu>
Cc: Dong Aisheng <dong.aisheng@linaro.org>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Huang Shijie <shijie8@gmail.com>
Cc: Javier Martin <javier.martin@vista-silicon.com>
Cc: Matt Porter <mporter@ti.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:13 -07:00