linux.git/drivers/misc/sram.c, branch v6.12.80

misc: sram: Convert to platform remove callback returning void

2024-03-05T14:28:52+00:00

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König 
Acked-by: Arnd Bergmann 
Link: https://lore.kernel.org/r/946ebc33a01bf700171257cd219fbe8626bc0c99.1708508896.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman

misc: Explicitly include correct DT includes

2023-08-04T13:39:04+00:00

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Acked-by: Andrew Donnellan  # cxl
Signed-off-by: Rob Herring 
Link: https://lore.kernel.org/r/20230718143102.1065481-1-robh@kernel.org
Signed-off-by: Greg Kroah-Hartman

misc/genalloc: Name subpools by of_node_full_name()

2023-07-26T07:45:01+00:00

A previous commit tried to come up with more generic subpool
names, but this isn't quite working: the node name was used
elsewhere to match pools to consumers which regressed the
nVidia Tegra 2/3 video decoder.

Revert back to an earlier approach using of_node_full_name()
instead of just the name to make sure the pool name is more
unique, and change both sites using this in the kernel.

It is not perfect since two SRAM nodes could have the same
subpool name but it makes the situation better than before.

Reported-by: Dmitry Osipenko 
Fixes: 21e5a2d10c8f ("misc: sram: Generate unique names for subpools")
Signed-off-by: Linus Walleij 
Tested-by: Dmitry Osipenko 
Link: https://lore.kernel.org/r/20230622074520.3058027-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman

misc: sram: Generate unique names for subpools

2023-05-17T07:15:25+00:00

The current code will, if we do not specify unique labels
for the SRAM subnodes, fail to register several nodes named
the same.

Example:

sram@40020000 {
  (...)
  sram@0 {
    (...)
  };
  sram@1000 {
    (...)
  };
};

Since the child->name in both cases will be "sram" the
gen_pool_create() will fail because the name is not unique.

Use dev_name() for the device as this will have bus ID
set to the fully translated address for the node, and that
will always be unique.

Signed-off-by: Linus Walleij 
Link: https://lore.kernel.org/r/20230417-ux500-sram-v2-2-6e62ad551faa@linaro.org

misc/sram: Use of_property_read_bool() for boolean properties

2023-03-17T14:23:25+00:00

It is preferred to use typed property access functions (i.e.
of_property_read_ functions) rather than low-level
of_get_property/of_find_property functions for reading properties.
Convert reading boolean properties to to of_property_read_bool().

Signed-off-by: Rob Herring 
Reviewed-by: Arnd Bergmann 
Link: https://lore.kernel.org/r/20230310144713.1543544-1-robh@kernel.org
Signed-off-by: Greg Kroah-Hartman

misc: sram: Improve and simplify clk handling

2023-03-09T16:31:53+00:00

The current code tries to get an associated clk, ignores any errors in the
process and if there is a clock enables it unconditionally for the whole
lifetime of the sram device.

Instead use an "optional" variant of devm_clk_get() which handles the case
where no clk is needed for the sram device and do proper error handling
for the remaining error cases. Also use an "enabled" variant of
devm_clk_get() to simplify. With that .probe() is the only function using
struct sram_dev::clk, so it can be replaced by a local variable.

Signed-off-by: Uwe Kleine-König 
Reviewed-by: Philipp Zabel 
Link: https://lore.kernel.org/r/20230302091251.1852454-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman

misc: sram: Add compatible string for Tegra234 SYSRAM

2021-12-08T14:16:05+00:00

We want to use the same behavior as on Tegra186 and Tegra194, so add
this the compatible string for Tegra234 SYSRAM to the list.

Signed-off-by: Mikko Perttunen 
Signed-off-by: Thierry Reding 
Link: https://lore.kernel.org/r/20211208140541.520238-1-thierry.reding@gmail.com
Signed-off-by: Greg Kroah-Hartman

misc: sram: Only map reserved areas in Tegra SYSRAM

2021-08-05T12:27:46+00:00

On Tegra186 and later, a portion of the SYSRAM may be reserved for use
by TZ. Non-TZ memory accesses to this portion, including speculative
accesses, trigger SErrors that bring down the system. This does also
happen in practice occasionally (due to speculative accesses).

To fix the issue, add a flag to the SRAM driver to only map the
device tree-specified reserved areas depending on a flag set
based on the compatibility string. This would not affect non-Tegra
systems that rely on the entire thing being memory mapped.

If 64K pages are being used, we cannot exactly map the 4K regions
that are placed in SYSRAM - ioremap code instead aligns to closest
64K pages. However, since in practice the non-accessible memory area
is 64K aligned, these mappings do not overlap with the non-accessible
memory area and things work out.

Reviewed-by: Mian Yousaf Kaukab 
Signed-off-by: Mikko Perttunen 
Link: https://lore.kernel.org/r/20210715103423.1811101-1-mperttunen@nvidia.com
Signed-off-by: Greg Kroah-Hartman

driver core: Drop helper devm_platform_ioremap_resource_wc()

2021-05-27T13:51:33+00:00

Since the macro was introduced in 2019 (commit bb6243b4f73d ("drivers:
platform: provide devm_platform_ioremap_resource_wc()") there is only a
single user which hardly justifies the function for the small task it
provides.

So drop the helper and open-code it in the only user. Adapt the non-wc
case accordingly.

For a all-mod-config build on amd64 this change introduces the following
changes according to bloat-o-meter:

add/remove: 0/1 grow/shrink: 1/0 up/down: 20/-252 (-232)
Function                                     old     new   delta
devm_platform_ioremap_resource_wc            252       -    -252
sram_probe                                   796     816     +20

Signed-off-by: Uwe Kleine-König 
Link: https://lore.kernel.org/r/20210525103711.956438-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman

treewide: Change list_sort to use const pointers

2021-04-08T23:04:22+00:00

list_sort() internally casts the comparison function passed to it
to a different type with constant struct list_head pointers, and
uses this pointer to call the functions, which trips indirect call
Control-Flow Integrity (CFI) checking.

Instead of removing the consts, this change defines the
list_cmp_func_t type and changes the comparison function types of
all list_sort() callers to use const pointers, thus avoiding type
mismatches.

Suggested-by: Nick Desaulniers 
Signed-off-by: Sami Tolvanen 
Reviewed-by: Nick Desaulniers 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Kees Cook 
Tested-by: Nick Desaulniers 
Tested-by: Nathan Chancellor 
Signed-off-by: Kees Cook 
Link: https://lore.kernel.org/r/20210408182843.1754385-10-samitolvanen@google.com