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| author | Dave Airlie <airlied@redhat.com> | 2026-09-26 07:57:59 +1000 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2026-09-26 07:58:24 +1000 |
| commit | a9ed3aa9b87ee41e8ab3ff471b1331c154767e45 (patch) | |
| tree | cc62d74e0eb4905246978674461e78e2f9df2afd /drivers/soc/apple/tunable.c | |
| download | linux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.tar.gz linux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.zip | |
Merge tag 'drm-misc-fixes-2026-09-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixesgrafted
A number of fixes:
- bridge:
- samsung-dsim: fix GPIO lifetime
- client: Null pointer dereference fix
- imagination: error handling fix, page handling fix
- nouveau: fix reference leaks, double-frees, out-of-bounds accesses,
use-after-frees, don't reject config without SCDC, a number of
workarounds
- virtio: fix memory leak, reference leaks, null pointer dereference,
add pixel blend mode, cache coherency fix
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <self@mripard.dev>
Link: https://patch.msgid.link/arU22zzqUGDEco1y@houat
Diffstat (limited to 'drivers/soc/apple/tunable.c')
| -rw-r--r-- | drivers/soc/apple/tunable.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/soc/apple/tunable.c b/drivers/soc/apple/tunable.c new file mode 100644 index 000000000..659323839 --- /dev/null +++ b/drivers/soc/apple/tunable.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple Silicon hardware tunable support + * + * Each tunable is a list with each entry containing a offset into the MMIO + * region, a mask of bits to be cleared and a set of bits to be set. These + * tunables are passed along by the previous boot stages and vary from device + * to device such that they cannot be hardcoded in the individual drivers. + * + * Copyright (C) The Asahi Linux Contributors + */ + +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/overflow.h> +#include <linux/soc/apple/tunable.h> + +struct apple_tunable *devm_apple_tunable_parse(struct device *dev, + struct device_node *np, + const char *name, + struct resource *res) +{ + struct apple_tunable *tunable; + struct property *prop; + const __be32 *p; + size_t sz; + int i; + + if (resource_size(res) < 4) + return ERR_PTR(-EINVAL); + + prop = of_find_property(np, name, NULL); + if (!prop) + return ERR_PTR(-ENOENT); + + if (prop->length % (3 * sizeof(u32))) + return ERR_PTR(-EINVAL); + sz = prop->length / (3 * sizeof(u32)); + + tunable = devm_kzalloc(dev, struct_size(tunable, values, sz), GFP_KERNEL); + if (!tunable) + return ERR_PTR(-ENOMEM); + tunable->sz = sz; + + for (i = 0, p = NULL; i < tunable->sz; ++i) { + p = of_prop_next_u32(prop, p, &tunable->values[i].offset); + p = of_prop_next_u32(prop, p, &tunable->values[i].mask); + p = of_prop_next_u32(prop, p, &tunable->values[i].value); + + /* Sanity checks to catch bugs in our bootloader */ + if (tunable->values[i].offset % 4) + return ERR_PTR(-EINVAL); + if (tunable->values[i].offset > (resource_size(res) - 4)) + return ERR_PTR(-EINVAL); + } + + return tunable; +} +EXPORT_SYMBOL(devm_apple_tunable_parse); + +void apple_tunable_apply(void __iomem *regs, struct apple_tunable *tunable) +{ + size_t i; + + for (i = 0; i < tunable->sz; ++i) { + u32 val, old_val; + + old_val = readl(regs + tunable->values[i].offset); + val = old_val & ~tunable->values[i].mask; + val |= tunable->values[i].value; + if (val != old_val) + writel(val, regs + tunable->values[i].offset); + } +} +EXPORT_SYMBOL(apple_tunable_apply); + +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_AUTHOR("Sven Peter <sven@kernel.org>"); +MODULE_DESCRIPTION("Apple Silicon hardware tunable support"); |
