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authorSang-Heon Jeon <ekffu200098@gmail.com>2026-08-24 01:18:14 +0900
committerJulia Lawall <Julia.Lawall@inria.fr>2026-08-23 22:12:11 +0200
commit2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c (patch)
treedcc4da1d99f17541c5590ac63c77da4bf372a4ab /drivers/soc/apple/tunable.c
downloadlinux-stable-2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c.tar.gz
linux-stable-2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c.zip
coccinelle: alloc_cast: drop removed allocatorsgrafted
- pci_alloc_consistent() and pci_zalloc_consistent() were removed by commit 7968778914e5 ("PCI: Remove the deprecated "pci-dma-compat.h" API") - kmem_alloc() was removed by commit f078d4ea8276 ("xfs: convert kmem_alloc() to kmalloc()") - kmem_zalloc() was removed by commit 10634530f7ba ("xfs: convert kmem_zalloc() to kzalloc()") - kmem_zone_alloc() and kmem_zone_zalloc() were removed by commit bae633a4a283 ("xfs: remove xfs_zone_{alloc,zalloc} helpers") So drop them from the rules. No functional change. Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Diffstat (limited to 'drivers/soc/apple/tunable.c')
-rw-r--r--drivers/soc/apple/tunable.c80
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");