Mirrors/opensbi
3
0
Fork 1
mirror of https://github.com/riscv-software-src/opensbi.git synced 2026-05-23 14:21:32 +01:00
Code Issues Packages Projects Releases Wiki Activity

lib: utils: fdt_domain: add root-regions-inheritance policy

Browse Source 
Introduce root-regions-inheritance DT property to control
copying of root domain memregions. Support 'all' and 'm-only'
modes, always inheriting firmware and M-only regions; behavior
matches m-only policy when property is absent.

Signed-off-by: Yu-Chien Peter Lin <peter.lin@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260516072906.1427203-1-peter.lin@sifive.com
Signed-off-by: Anup Patel <anup@brainfault.org>
This commit is contained in:
Yu-Chien Peter Lin
2026-05-16 15:29:06 +08:00
committed by Anup Patel
parent 22d7e99ed2
commit f36acaeb80
2 changed files with 47 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files
docs/domain_support.md
+7
View File
@@ -159,6 +159,13 @@ The DT properties of a domain instance DT node are as follows:
* **possible-harts** (Optional) - The list of CPU DT node phandles for the
the domain instance. This list represents the possible HARTs of the
domain instance.
* **root-regions-inheritance** (Optional) - A string property controlling
how memory regions are inherited from **the ROOT domain**, which are then
overlaid with regions specified in the **regions** property for additional
restrictions. The allowed values are:
* "all" - inherit all memory regions from **the ROOT domain**
* "m-only" - inherit M-mode only memory regions from **the ROOT domain**
If this DT property is absent, behavior is the same as "m-only".
* **regions** (Optional) - The list of domain memory region DT node phandle
and access permissions for the domain instance. Each list entry is a pair
of DT node phandle and access permissions. The access permissions are
lib/utils/fdt/fdt_domain.c
+40 -13
View File
@@ -10,6 +10,7 @@
#include <libfdt.h>
#include <libfdt_env.h>
#include <sbi/sbi_console.h>
#include <sbi/sbi_domain.h>
#include <sbi/sbi_error.h>
#include <sbi/sbi_hartmask.h>
@@ -237,7 +238,9 @@ skip_device_disable:
fdt_nop_node(fdt, poffset);
}
#define FDT_DOMAIN_REGION_MAX_COUNT 16
#define FDT_DOMAIN_REGION_MAX_COUNT 16
#define FDT_ROOT_REGION_INHERIT_M_ONLY 0
#define FDT_ROOT_REGION_INHERIT_ALL 1
struct parse_region_data {
struct sbi_domain *dom;
@@ -309,12 +312,14 @@ static int __fdt_parse_domain(const void *fdt, int domain_offset, void *opaque)
u32 val32;
u64 val64;
const u32 *val;
const char *inherit;
struct sbi_domain *dom;
struct sbi_hartmask *mask;
struct sbi_hartmask assign_mask;
struct parse_region_data preg;
int *cold_domain_offset = opaque;
struct sbi_domain_memregion *reg;
int inheritance_mode = FDT_ROOT_REGION_INHERIT_M_ONLY;
int i, err = 0, len, cpus_offset, cpu_offset, doffset;
dom = sbi_zalloc(sizeof(*dom));
@@ -373,20 +378,42 @@ static int __fdt_parse_domain(const void *fdt, int domain_offset, void *opaque)
if (err)
goto fail_free_all;
/*
* Copy over root domain memregions which don't allow
* read, write and execute from lower privilege modes.
*
* These root domain memregions without read, write,
* and execute permissions include:
* 1) firmware region protecting the firmware memory
* 2) mmio regions protecting M-mode only mmio devices
*/
/* Determine root domain regions inheritance behavior. */
inherit = fdt_getprop(fdt, domain_offset,
"root-regions-inheritance", &len);
if (inherit && len > 0) {
if (!strcmp(inherit, "all"))
inheritance_mode = FDT_ROOT_REGION_INHERIT_ALL;
else if (!strcmp(inherit, "m-only"))
inheritance_mode = FDT_ROOT_REGION_INHERIT_M_ONLY;
else {
sbi_printf("%s: domain \"%s\" has unsupported "
"root-regions-inheritance=\"%s\"\n",
__func__, dom->name, inherit);
err = SBI_EINVAL;
goto fail_free_all;
}
}
/* Copy over root domain memregions according to inheritance_mode. */
sbi_domain_for_each_memregion(&root, reg) {
if ((reg->flags & SBI_DOMAIN_MEMREGION_SU_READABLE) ||
(reg->flags & SBI_DOMAIN_MEMREGION_SU_WRITABLE) ||
(reg->flags & SBI_DOMAIN_MEMREGION_SU_EXECUTABLE))
bool copy = false;
switch (inheritance_mode) {
case FDT_ROOT_REGION_INHERIT_ALL:
copy = true;
break;
case FDT_ROOT_REGION_INHERIT_M_ONLY:
if (SBI_DOMAIN_MEMREGION_IS_FIRMWARE(reg->flags) ||
SBI_DOMAIN_MEMREGION_M_ONLY_ACCESS(reg->flags)) {
copy = true;
}
break;
}
if (!copy)
continue;
if (preg.max_regions <= preg.region_count) {
err = SBI_EINVAL;
goto fail_free_all;