From: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
To: <xen-devel@lists.xenproject.org>
Cc: Ayan Kumar Halder <ayan.kumar.halder@amd.com>,
Stefano Stabellini <sstabellini@kernel.org>,
Julien Grall <julien@xen.org>,
Bertrand Marquis <bertrand.marquis@arm.com>,
Michal Orzel <michal.orzel@amd.com>,
"Volodymyr Babchuk" <Volodymyr_Babchuk@epam.com>,
Luca Fancellu <luca.fancellu@arm.com>
Subject: [PATCH v5 1/3] arm/mpu: Move the functions to arm64 specific files
Date: Thu, 19 Jun 2025 12:31:50 +0100 [thread overview]
Message-ID: <20250619113152.2723066-2-ayan.kumar.halder@amd.com> (raw)
In-Reply-To: <20250619113152.2723066-1-ayan.kumar.halder@amd.com>
prepare_selector(), read_protection_region() and write_protection_region()
differ significantly between arm32 and arm64. Thus, move these functions
to their sub-arch specific folder.
Also the macro GENERATE_{WRITE/READ}_PR_REG_CASE are moved, in order to
keep them in the same file of their usage and improve readability.
Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Michal Orzel <michal.orzel@amd.com>
---
Changes from -
v2 - New patch introduced in v3.
v3 - 1. Add Luca's R-b.
v4 - 1. Reorder entries in mpu/Makefile alphabetically.
2. Add Michal's A-b.
xen/arch/arm/mpu/Makefile | 1 +
xen/arch/arm/mpu/arm64/Makefile | 1 +
xen/arch/arm/mpu/arm64/mm.c | 130 ++++++++++++++++++++++++++++++++
xen/arch/arm/mpu/mm.c | 117 ----------------------------
4 files changed, 132 insertions(+), 117 deletions(-)
create mode 100644 xen/arch/arm/mpu/arm64/Makefile
create mode 100644 xen/arch/arm/mpu/arm64/mm.c
diff --git a/xen/arch/arm/mpu/Makefile b/xen/arch/arm/mpu/Makefile
index 808e3e2cb3..09326a5248 100644
--- a/xen/arch/arm/mpu/Makefile
+++ b/xen/arch/arm/mpu/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_ARM_64) += arm64/
obj-$(CONFIG_ARM_32) += domain-page.o
obj-y += mm.o
obj-y += p2m.o
diff --git a/xen/arch/arm/mpu/arm64/Makefile b/xen/arch/arm/mpu/arm64/Makefile
new file mode 100644
index 0000000000..b18cec4836
--- /dev/null
+++ b/xen/arch/arm/mpu/arm64/Makefile
@@ -0,0 +1 @@
+obj-y += mm.o
diff --git a/xen/arch/arm/mpu/arm64/mm.c b/xen/arch/arm/mpu/arm64/mm.c
new file mode 100644
index 0000000000..ed643cad40
--- /dev/null
+++ b/xen/arch/arm/mpu/arm64/mm.c
@@ -0,0 +1,130 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <xen/bug.h>
+#include <xen/types.h>
+#include <asm/mpu.h>
+#include <asm/sysregs.h>
+#include <asm/system.h>
+
+/*
+ * The following are needed for the cases: GENERATE_WRITE_PR_REG_CASE
+ * and GENERATE_READ_PR_REG_CASE with num==0
+ */
+#define PRBAR0_EL2 PRBAR_EL2
+#define PRLAR0_EL2 PRLAR_EL2
+
+#define PRBAR_EL2_(n) PRBAR##n##_EL2
+#define PRLAR_EL2_(n) PRLAR##n##_EL2
+
+#define GENERATE_WRITE_PR_REG_CASE(num, pr) \
+ case num: \
+ { \
+ WRITE_SYSREG(pr->prbar.bits & ~MPU_REGION_RES0, PRBAR_EL2_(num)); \
+ WRITE_SYSREG(pr->prlar.bits & ~MPU_REGION_RES0, PRLAR_EL2_(num)); \
+ break; \
+ }
+
+#define GENERATE_READ_PR_REG_CASE(num, pr) \
+ case num: \
+ { \
+ pr->prbar.bits = READ_SYSREG(PRBAR_EL2_(num)); \
+ pr->prlar.bits = READ_SYSREG(PRLAR_EL2_(num)); \
+ break; \
+ }
+
+/*
+ * Armv8-R supports direct access and indirect access to the MPU regions through
+ * registers:
+ * - indirect access involves changing the MPU region selector, issuing an isb
+ * barrier and accessing the selected region through specific registers
+ * - direct access involves accessing specific registers that point to
+ * specific MPU regions, without changing the selector, avoiding the use of
+ * a barrier.
+ * For Arm64 the PR{B,L}AR_ELx (for n=0) and PR{B,L}AR<n>_ELx (for n=1..15) are
+ * used for the direct access to the regions selected by
+ * PRSELR_EL2.REGION<7:4>:n, so 16 regions can be directly accessed when the
+ * selector is a multiple of 16, giving access to all the supported memory
+ * regions.
+ */
+static void prepare_selector(uint8_t *sel)
+{
+ uint8_t cur_sel = *sel;
+
+ /*
+ * {read,write}_protection_region works using the direct access to the 0..15
+ * regions, so in order to save the isb() overhead, change the PRSELR_EL2
+ * only when needed, so when the upper 4 bits of the selector will change.
+ */
+ cur_sel &= 0xF0U;
+ if ( READ_SYSREG(PRSELR_EL2) != cur_sel )
+ {
+ WRITE_SYSREG(cur_sel, PRSELR_EL2);
+ isb();
+ }
+ *sel &= 0xFU;
+}
+
+void read_protection_region(pr_t *pr_read, uint8_t sel)
+{
+ prepare_selector(&sel);
+
+ switch ( sel )
+ {
+ GENERATE_READ_PR_REG_CASE(0, pr_read);
+ GENERATE_READ_PR_REG_CASE(1, pr_read);
+ GENERATE_READ_PR_REG_CASE(2, pr_read);
+ GENERATE_READ_PR_REG_CASE(3, pr_read);
+ GENERATE_READ_PR_REG_CASE(4, pr_read);
+ GENERATE_READ_PR_REG_CASE(5, pr_read);
+ GENERATE_READ_PR_REG_CASE(6, pr_read);
+ GENERATE_READ_PR_REG_CASE(7, pr_read);
+ GENERATE_READ_PR_REG_CASE(8, pr_read);
+ GENERATE_READ_PR_REG_CASE(9, pr_read);
+ GENERATE_READ_PR_REG_CASE(10, pr_read);
+ GENERATE_READ_PR_REG_CASE(11, pr_read);
+ GENERATE_READ_PR_REG_CASE(12, pr_read);
+ GENERATE_READ_PR_REG_CASE(13, pr_read);
+ GENERATE_READ_PR_REG_CASE(14, pr_read);
+ GENERATE_READ_PR_REG_CASE(15, pr_read);
+ default:
+ BUG(); /* Can't happen */
+ break;
+ }
+}
+
+void write_protection_region(const pr_t *pr_write, uint8_t sel)
+{
+ prepare_selector(&sel);
+
+ switch ( sel )
+ {
+ GENERATE_WRITE_PR_REG_CASE(0, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(1, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(2, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(3, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(4, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(5, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(6, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(7, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(8, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(9, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(10, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(11, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(12, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(13, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(14, pr_write);
+ GENERATE_WRITE_PR_REG_CASE(15, pr_write);
+ default:
+ BUG(); /* Can't happen */
+ break;
+ }
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/arch/arm/mpu/mm.c b/xen/arch/arm/mpu/mm.c
index 3d37beab57..7ab68fc8c7 100644
--- a/xen/arch/arm/mpu/mm.c
+++ b/xen/arch/arm/mpu/mm.c
@@ -29,35 +29,6 @@ DECLARE_BITMAP(xen_mpumap_mask, MAX_MPU_REGION_NR) \
/* EL2 Xen MPU memory region mapping table. */
pr_t __cacheline_aligned __section(".data") xen_mpumap[MAX_MPU_REGION_NR];
-#ifdef CONFIG_ARM_64
-/*
- * The following are needed for the cases: GENERATE_WRITE_PR_REG_CASE
- * and GENERATE_READ_PR_REG_CASE with num==0
- */
-#define PRBAR0_EL2 PRBAR_EL2
-#define PRLAR0_EL2 PRLAR_EL2
-
-#define PRBAR_EL2_(n) PRBAR##n##_EL2
-#define PRLAR_EL2_(n) PRLAR##n##_EL2
-
-#endif /* CONFIG_ARM_64 */
-
-#define GENERATE_WRITE_PR_REG_CASE(num, pr) \
- case num: \
- { \
- WRITE_SYSREG(pr->prbar.bits & ~MPU_REGION_RES0, PRBAR_EL2_(num)); \
- WRITE_SYSREG(pr->prlar.bits & ~MPU_REGION_RES0, PRLAR_EL2_(num)); \
- break; \
- }
-
-#define GENERATE_READ_PR_REG_CASE(num, pr) \
- case num: \
- { \
- pr->prbar.bits = READ_SYSREG(PRBAR_EL2_(num)); \
- pr->prlar.bits = READ_SYSREG(PRLAR_EL2_(num)); \
- break; \
- }
-
static void __init __maybe_unused build_assertions(void)
{
/*
@@ -69,94 +40,6 @@ static void __init __maybe_unused build_assertions(void)
}
#ifdef CONFIG_ARM_64
-/*
- * Armv8-R supports direct access and indirect access to the MPU regions through
- * registers:
- * - indirect access involves changing the MPU region selector, issuing an isb
- * barrier and accessing the selected region through specific registers
- * - direct access involves accessing specific registers that point to
- * specific MPU regions, without changing the selector, avoiding the use of
- * a barrier.
- * For Arm64 the PR{B,L}AR_ELx (for n=0) and PR{B,L}AR<n>_ELx (for n=1..15) are
- * used for the direct access to the regions selected by
- * PRSELR_EL2.REGION<7:4>:n, so 16 regions can be directly accessed when the
- * selector is a multiple of 16, giving access to all the supported memory
- * regions.
- */
-static void prepare_selector(uint8_t *sel)
-{
- uint8_t cur_sel = *sel;
-
- /*
- * {read,write}_protection_region works using the direct access to the 0..15
- * regions, so in order to save the isb() overhead, change the PRSELR_EL2
- * only when needed, so when the upper 4 bits of the selector will change.
- */
- cur_sel &= 0xF0U;
- if ( READ_SYSREG(PRSELR_EL2) != cur_sel )
- {
- WRITE_SYSREG(cur_sel, PRSELR_EL2);
- isb();
- }
- *sel &= 0xFU;
-}
-
-void read_protection_region(pr_t *pr_read, uint8_t sel)
-{
- prepare_selector(&sel);
-
- switch ( sel )
- {
- GENERATE_READ_PR_REG_CASE(0, pr_read);
- GENERATE_READ_PR_REG_CASE(1, pr_read);
- GENERATE_READ_PR_REG_CASE(2, pr_read);
- GENERATE_READ_PR_REG_CASE(3, pr_read);
- GENERATE_READ_PR_REG_CASE(4, pr_read);
- GENERATE_READ_PR_REG_CASE(5, pr_read);
- GENERATE_READ_PR_REG_CASE(6, pr_read);
- GENERATE_READ_PR_REG_CASE(7, pr_read);
- GENERATE_READ_PR_REG_CASE(8, pr_read);
- GENERATE_READ_PR_REG_CASE(9, pr_read);
- GENERATE_READ_PR_REG_CASE(10, pr_read);
- GENERATE_READ_PR_REG_CASE(11, pr_read);
- GENERATE_READ_PR_REG_CASE(12, pr_read);
- GENERATE_READ_PR_REG_CASE(13, pr_read);
- GENERATE_READ_PR_REG_CASE(14, pr_read);
- GENERATE_READ_PR_REG_CASE(15, pr_read);
- default:
- BUG(); /* Can't happen */
- break;
- }
-}
-
-void write_protection_region(const pr_t *pr_write, uint8_t sel)
-{
- prepare_selector(&sel);
-
- switch ( sel )
- {
- GENERATE_WRITE_PR_REG_CASE(0, pr_write);
- GENERATE_WRITE_PR_REG_CASE(1, pr_write);
- GENERATE_WRITE_PR_REG_CASE(2, pr_write);
- GENERATE_WRITE_PR_REG_CASE(3, pr_write);
- GENERATE_WRITE_PR_REG_CASE(4, pr_write);
- GENERATE_WRITE_PR_REG_CASE(5, pr_write);
- GENERATE_WRITE_PR_REG_CASE(6, pr_write);
- GENERATE_WRITE_PR_REG_CASE(7, pr_write);
- GENERATE_WRITE_PR_REG_CASE(8, pr_write);
- GENERATE_WRITE_PR_REG_CASE(9, pr_write);
- GENERATE_WRITE_PR_REG_CASE(10, pr_write);
- GENERATE_WRITE_PR_REG_CASE(11, pr_write);
- GENERATE_WRITE_PR_REG_CASE(12, pr_write);
- GENERATE_WRITE_PR_REG_CASE(13, pr_write);
- GENERATE_WRITE_PR_REG_CASE(14, pr_write);
- GENERATE_WRITE_PR_REG_CASE(15, pr_write);
- default:
- BUG(); /* Can't happen */
- break;
- }
-}
-
pr_t pr_of_addr(paddr_t base, paddr_t limit, unsigned int flags)
{
unsigned int attr_idx = PAGE_AI_MASK(flags);
--
2.25.1
next prev parent reply other threads:[~2025-06-19 11:32 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-06-19 11:31 [PATCH v5 0/3] Enable R52 support for the first chunk of MPU support Ayan Kumar Halder
2025-06-19 11:31 ` Ayan Kumar Halder [this message]
2025-06-19 11:31 ` [PATCH v5 2/3] arm/mpu: Define arm32 system registers Ayan Kumar Halder
2025-06-19 11:31 ` [PATCH v5 3/3] arm/mpu: Enable read/write to protection regions for arm32 Ayan Kumar Halder
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