diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-12-05 17:47:59 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-12-05 17:47:59 -0800 |
| commit | 11efc1cb7016e300047822fd60e0f4b4158bd56d (patch) | |
| tree | 1bf4295f1e5d5ce3e90b7716d4b755d5b08f56f5 /lib/cache_maint.c | |
| parent | 208eed95fc710827b100266c9450ae84d46727bd (diff) | |
| parent | 68f9bbf4dfc356ccc6586ba6e7dd79576c48f7f0 (diff) | |
Merge tag 'soc-drivers-6.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull more SoC driver updates from Arnd Bergmann:
"These updates came a little late, or were based on a later 6.18-rc tag
than the others:
- A new driver for cache management on cxl devices with memory shared
in a coherent cluster. This is part of the drivers/cache/ tree, but
unlike the other drivers that back the dma-mapping interfaces, this
one is needed only during CPU hotplug.
- A shared branch for reset controllers using swnode infrastructure
- Added support for new SoC variants in the Amlogic soc_device
identification
- Minor updates in Freescale, Microchip, Samsung, and Apple SoC
drivers"
* tag 'soc-drivers-6.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (24 commits)
soc: samsung: exynos-pmu: fix device leak on regmap lookup
soc: samsung: exynos-pmu: Fix structure initialization
soc: fsl: qbman: use kmalloc_array() instead of kmalloc()
soc: fsl: qbman: add WQ_PERCPU to alloc_workqueue users
MAINTAINERS: Update email address for Christophe Leroy
MAINTAINERS: refer to intended file in STANDALONE CACHE CONTROLLER DRIVERS
cache: Support cache maintenance for HiSilicon SoC Hydra Home Agent
cache: Make top level Kconfig menu a boolean dependent on RISCV
MAINTAINERS: Add Jonathan Cameron to drivers/cache and add lib/cache_maint.c + header
arm64: Select GENERIC_CPU_CACHE_MAINTENANCE
lib: Support ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION
soc: amlogic: meson-gx-socinfo: add new SoCs id
dt-bindings: arm: amlogic: meson-gx-ao-secure: support more SoCs
memregion: Support fine grained invalidate by cpu_cache_invalidate_memregion()
memregion: Drop unused IORES_DESC_* parameter from cpu_cache_invalidate_memregion()
dt-bindings: cache: sifive,ccache0: add a pic64gx compatible
MAINTAINERS: rename Microchip RISC-V entry
MAINTAINERS: add new soc drivers to Microchip RISC-V entry
soc: microchip: add mfd drivers for two syscon regions on PolarFire SoC
dt-bindings: soc: microchip: document the simple-mfd syscon on PolarFire SoC
...
Diffstat (limited to 'lib/cache_maint.c')
| -rw-r--r-- | lib/cache_maint.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/lib/cache_maint.c b/lib/cache_maint.c new file mode 100644 index 000000000000..9256a9ffc34c --- /dev/null +++ b/lib/cache_maint.c @@ -0,0 +1,138 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Generic support for Memory System Cache Maintenance operations. + * + * Coherency maintenance drivers register with this simple framework that will + * iterate over each registered instance to first kick off invalidation and + * then to wait until it is complete. + * + * If no implementations are registered yet cpu_cache_has_invalidate_memregion() + * will return false. If this runs concurrently with unregistration then a + * race exists but this is no worse than the case where the operations instance + * responsible for a given memory region has not yet registered. + */ +#include <linux/cache_coherency.h> +#include <linux/cleanup.h> +#include <linux/container_of.h> +#include <linux/export.h> +#include <linux/kref.h> +#include <linux/list.h> +#include <linux/memregion.h> +#include <linux/module.h> +#include <linux/rwsem.h> +#include <linux/slab.h> + +static LIST_HEAD(cache_ops_instance_list); +static DECLARE_RWSEM(cache_ops_instance_list_lock); + +static void __cache_coherency_ops_instance_free(struct kref *kref) +{ + struct cache_coherency_ops_inst *cci = + container_of(kref, struct cache_coherency_ops_inst, kref); + kfree(cci); +} + +void cache_coherency_ops_instance_put(struct cache_coherency_ops_inst *cci) +{ + kref_put(&cci->kref, __cache_coherency_ops_instance_free); +} +EXPORT_SYMBOL_GPL(cache_coherency_ops_instance_put); + +static int cache_inval_one(struct cache_coherency_ops_inst *cci, void *data) +{ + if (!cci->ops) + return -EINVAL; + + return cci->ops->wbinv(cci, data); +} + +static int cache_inval_done_one(struct cache_coherency_ops_inst *cci) +{ + if (!cci->ops) + return -EINVAL; + + if (!cci->ops->done) + return 0; + + return cci->ops->done(cci); +} + +static int cache_invalidate_memregion(phys_addr_t addr, size_t size) +{ + int ret; + struct cache_coherency_ops_inst *cci; + struct cc_inval_params params = { + .addr = addr, + .size = size, + }; + + guard(rwsem_read)(&cache_ops_instance_list_lock); + list_for_each_entry(cci, &cache_ops_instance_list, node) { + ret = cache_inval_one(cci, ¶ms); + if (ret) + return ret; + } + list_for_each_entry(cci, &cache_ops_instance_list, node) { + ret = cache_inval_done_one(cci); + if (ret) + return ret; + } + + return 0; +} + +struct cache_coherency_ops_inst * +_cache_coherency_ops_instance_alloc(const struct cache_coherency_ops *ops, + size_t size) +{ + struct cache_coherency_ops_inst *cci; + + if (!ops || !ops->wbinv) + return NULL; + + cci = kzalloc(size, GFP_KERNEL); + if (!cci) + return NULL; + + cci->ops = ops; + INIT_LIST_HEAD(&cci->node); + kref_init(&cci->kref); + + return cci; +} +EXPORT_SYMBOL_NS_GPL(_cache_coherency_ops_instance_alloc, "CACHE_COHERENCY"); + +int cache_coherency_ops_instance_register(struct cache_coherency_ops_inst *cci) +{ + guard(rwsem_write)(&cache_ops_instance_list_lock); + list_add(&cci->node, &cache_ops_instance_list); + + return 0; +} +EXPORT_SYMBOL_NS_GPL(cache_coherency_ops_instance_register, "CACHE_COHERENCY"); + +void cache_coherency_ops_instance_unregister(struct cache_coherency_ops_inst *cci) +{ + guard(rwsem_write)(&cache_ops_instance_list_lock); + list_del(&cci->node); +} +EXPORT_SYMBOL_NS_GPL(cache_coherency_ops_instance_unregister, "CACHE_COHERENCY"); + +int cpu_cache_invalidate_memregion(phys_addr_t start, size_t len) +{ + return cache_invalidate_memregion(start, len); +} +EXPORT_SYMBOL_NS_GPL(cpu_cache_invalidate_memregion, "DEVMEM"); + +/* + * Used for optimization / debug purposes only as removal can race + * + * Machines that do not support invalidation, e.g. VMs, will not have any + * operations instance to register and so this will always return false. + */ +bool cpu_cache_has_invalidate_memregion(void) +{ + guard(rwsem_read)(&cache_ops_instance_list_lock); + return !list_empty(&cache_ops_instance_list); +} +EXPORT_SYMBOL_NS_GPL(cpu_cache_has_invalidate_memregion, "DEVMEM"); |