[PATCH v6 04/11] lib: utils/cache: Add fdt cmo helpers
Nick Hu
nick.hu at sifive.com
Thu Sep 4 19:24:37 PDT 2025
Add the helpers to build up the cache hierarchy via FDT and provide some
cmo functions for the user who want to flush the entire cache.
Signed-off-by: Nick Hu <nick.hu at sifive.com>
Reviewed-by: Samuel Holland <samuel.holland at sifive.com>
Reviewed-by: Anup Patel <anup at brainfault.org>
---
include/sbi_utils/cache/fdt_cmo_helper.h | 40 +++++++++++
lib/utils/cache/fdt_cmo_helper.c | 112 +++++++++++++++++++++++++++++++
lib/utils/cache/objects.mk | 1 +
platform/generic/platform.c | 3 +-
4 files changed, 155 insertions(+), 1 deletion(-)
diff --git a/include/sbi_utils/cache/fdt_cmo_helper.h b/include/sbi_utils/cache/fdt_cmo_helper.h
new file mode 100644
index 0000000000000000000000000000000000000000..a6a28db9ede2722d8261d2e077eeb7710cff0893
--- /dev/null
+++ b/include/sbi_utils/cache/fdt_cmo_helper.h
@@ -0,0 +1,40 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2025 SiFive Inc.
+ */
+
+#ifndef __FDT_CMO_HELPER_H__
+#define __FDT_CMO_HELPER_H__
+
+#ifdef CONFIG_FDT_CACHE
+/**
+ * Flush the private first level cache of the current hart
+ *
+ * @return 0 on success, or a negative error code on failure
+ */
+int fdt_cmo_private_flc_flush_all(void);
+
+/**
+ * Flush the last level cache of the current hart
+ *
+ * @return 0 on success, or a negative error code on failure
+ */
+int fdt_cmo_llc_flush_all(void);
+
+/**
+ * Initialize the cache devices for each hart
+ *
+ * @param fdt devicetree blob
+ * @param cold_boot cold init or warm init
+ *
+ * @return 0 on success, or a negative error code on failure
+ */
+int fdt_cmo_init(bool cold_boot);
+
+#else
+
+static inline int fdt_cmo_init(bool cold_boot) { return 0; }
+
+#endif /* CONFIG_FDT_CACHE */
+#endif /* __FDT_CMO_HELPER_H__ */
diff --git a/lib/utils/cache/fdt_cmo_helper.c b/lib/utils/cache/fdt_cmo_helper.c
new file mode 100644
index 0000000000000000000000000000000000000000..6d2e853dd735735092c57db2398f97a64de3ab5e
--- /dev/null
+++ b/lib/utils/cache/fdt_cmo_helper.c
@@ -0,0 +1,112 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2025 SiFive Inc.
+ */
+
+#include <libfdt.h>
+#include <sbi/sbi_error.h>
+#include <sbi/sbi_scratch.h>
+#include <sbi_utils/cache/fdt_cache.h>
+#include <sbi_utils/cache/fdt_cmo_helper.h>
+#include <sbi_utils/fdt/fdt_helper.h>
+
+static unsigned long flc_offset;
+
+#define get_hart_flc(_s) \
+ sbi_scratch_read_type(_s, struct cache_device *, flc_offset)
+#define set_hart_flc(_s, _p) \
+ sbi_scratch_write_type(_s, struct cache_device *, flc_offset, _p)
+
+int fdt_cmo_private_flc_flush_all(void)
+{
+ struct cache_device *flc = get_hart_flc(sbi_scratch_thishart_ptr());
+
+ if (!flc || !flc->cpu_private)
+ return SBI_ENODEV;
+
+ return cache_flush_all(flc);
+}
+
+int fdt_cmo_llc_flush_all(void)
+{
+ struct cache_device *llc = get_hart_flc(sbi_scratch_thishart_ptr());
+
+ if (!llc)
+ return SBI_ENODEV;
+
+ while (llc->next)
+ llc = llc->next;
+
+ return cache_flush_all(llc);
+}
+
+static int fdt_cmo_cold_init(const void *fdt)
+{
+ struct sbi_scratch *scratch;
+ struct cache_device *dev;
+ int cpu_offset, cpus_offset, rc;
+ u32 hartid;
+
+ cpus_offset = fdt_path_offset(fdt, "/cpus");
+ if (cpus_offset < 0)
+ return SBI_EINVAL;
+
+ fdt_for_each_subnode(cpu_offset, fdt, cpus_offset) {
+ rc = fdt_parse_hart_id(fdt, cpu_offset, &hartid);
+ if (rc)
+ continue;
+
+ scratch = sbi_hartid_to_scratch(hartid);
+ if (!scratch)
+ continue;
+
+ rc = fdt_next_cache_get(fdt, cpu_offset, &dev);
+ if (rc)
+ return rc;
+
+ set_hart_flc(scratch, dev);
+ }
+
+ return SBI_OK;
+}
+
+static int fdt_cmo_warm_init(void)
+{
+ struct cache_device *cur = get_hart_flc(sbi_scratch_thishart_ptr());
+ int rc;
+
+ while (cur) {
+ if (cur->ops && cur->ops->warm_init) {
+ rc = cur->ops->warm_init(cur);
+ if (rc)
+ return rc;
+ }
+
+ cur = cur->next;
+ }
+
+ return SBI_OK;
+}
+
+int fdt_cmo_init(bool cold_boot)
+{
+ const void *fdt = fdt_get_address();
+ int rc;
+
+ if (cold_boot) {
+ flc_offset = sbi_scratch_alloc_type_offset(struct cache_device *);
+ if (!flc_offset)
+ return SBI_ENOMEM;
+
+ rc = fdt_cmo_cold_init(fdt);
+ if (rc)
+ return rc;
+ }
+
+ rc = fdt_cmo_warm_init();
+ if (rc)
+ return rc;
+
+ return SBI_OK;
+}
diff --git a/lib/utils/cache/objects.mk b/lib/utils/cache/objects.mk
index a343eb8c4bd495a1596845c1fd02420277023430..6829a966784732127d93180b3eb46ed24de5bc7d 100644
--- a/lib/utils/cache/objects.mk
+++ b/lib/utils/cache/objects.mk
@@ -6,6 +6,7 @@
libsbiutils-objs-$(CONFIG_FDT_CACHE) += cache/fdt_cache.o
libsbiutils-objs-$(CONFIG_FDT_CACHE) += cache/fdt_cache_drivers.carray.o
+libsbiutils-objs-$(CONFIG_FDT_CACHE) += cache/fdt_cmo_helper.o
carray-fdt_cache_drivers-$(CONFIG_FDT_CACHE_SIFIVE_CCACHE) += fdt_sifive_ccache
libsbiutils-objs-$(CONFIG_FDT_CACHE_SIFIVE_CCACHE) += cache/fdt_sifive_ccache.o
diff --git a/platform/generic/platform.c b/platform/generic/platform.c
index 91140958a0f4294428221c91fe2792eb6b1b02d5..e66f99fa8a88d1badd3843305e34486a548bf465 100644
--- a/platform/generic/platform.c
+++ b/platform/generic/platform.c
@@ -17,6 +17,7 @@
#include <sbi/sbi_string.h>
#include <sbi/sbi_system.h>
#include <sbi/sbi_tlb.h>
+#include <sbi_utils/cache/fdt_cmo_helper.h>
#include <sbi_utils/fdt/fdt_domain.h>
#include <sbi_utils/fdt/fdt_driver.h>
#include <sbi_utils/fdt/fdt_fixup.h>
@@ -230,7 +231,7 @@ int generic_early_init(bool cold_boot)
fdt_driver_init_all(fdt, fdt_early_drivers);
}
- return 0;
+ return fdt_cmo_init(cold_boot);
}
int generic_final_init(bool cold_boot)
--
2.34.1
More information about the opensbi
mailing list