@@ -1,5 +1,6 @@
obj-y += lib/
obj-$(CONFIG_MMU) += mmu/
+obj-$(CONFIG_MPU) += mpu/
obj-$(CONFIG_EARLY_PRINTK) += debug.o
obj-y += domctl.o
new file mode 100644
@@ -0,0 +1 @@
+obj-y += head.o
new file mode 100644
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Start-of-day code for an Armv8-R MPU system.
+ */
+
+#include <asm/page.h>
+#include <asm/mpu/prepare_xen_region.inc>
+
+/*
+ * Set up the memory attribute type tables and enable EL2 MPU and data cache.
+ * If the Background region is enabled, then the MPU uses the default memory
+ * map as the Background region for generating the memory
+ * attributes when MPU is disabled.
+ * Since the default memory map of the Armv8-R AArch32 architecture is
+ * IMPLEMENTATION DEFINED, we intend to turn off the Background region here.
+ *
+ * Clobbers r0 - r1
+ */
+FUNC_LOCAL(enable_mpu)
+ /* Set up memory attribute type tables */
+ mov_w r0, MAIR0VAL
+ mov_w r1, MAIR1VAL
+ mcr CP32(r0, HMAIR0)
+ mcr CP32(r1, HMAIR1)
+
+ mrc CP32(r0, HSCTLR)
+ bic r0, r0, #SCTLR_ELx_BR /* Disable Background region */
+ orr r0, r0, #SCTLR_Axx_ELx_M /* Enable MPU */
+ orr r0, r0, #SCTLR_Axx_ELx_C /* Enable D-cache */
+ mcr CP32(r0, HSCTLR)
+ isb
+ mov pc, lr
+END(enable_mpu)
+
+/*
+ * Maps the various sections of Xen (decsribed in xen.lds.S) as different MPU
+ * regions.
+ *
+ * Clobbers r0 - r6
+ */
+FUNC(enable_boot_cpu_mm)
+ mov r6, lr
+ enable_boot_cpu r0, r1, r2, r3, r4, r5
+ mov pc, r6
+END(enable_boot_cpu_mm)
+
+/*
+ * Local variables:
+ * mode: ASM
+ * indent-tabs-mode: nil
+ * End:
+ */
@@ -4,6 +4,14 @@
#include <xen/stringify.h>
#include <asm/cpregs.h>
+#define REGION_TEXT_PRBAR 0x18 /* SH=11 AP=10 XN=0 */
+#define REGION_RO_PRBAR 0x1D /* SH=11 AP=10 XN=1 */
+#define REGION_DATA_PRBAR 0x19 /* SH=11 AP=00 XN=1 */
+#define REGION_DEVICE_PRBAR 0x11 /* SH=10 AP=00 XN=1 */
+
+#define REGION_NORMAL_PRLAR 0x0f /* NS=0 ATTR=111 EN=1 */
+#define REGION_DEVICE_PRLAR 0x09 /* NS=0 ATTR=100 EN=1 */
+
/* Layout as used in assembly, with src/dest registers mixed in */
#define __CP32(r, coproc, opc1, crn, crm, opc2) coproc, opc1, r, crn, crm, opc2
#define __CP64(r1, r2, coproc, opc, crm) coproc, opc, r1, r2, crm
@@ -16,6 +24,9 @@
#define LOAD_CP64(r, name...) "mrrc " __stringify(CP64(%r, %H##r, name)) ";"
#define STORE_CP64(r, name...) "mcrr " __stringify(CP64(%r, %H##r, name)) ";"
+#define LOAD_SYSREG(v, name) mrc CP32(v, name)
+#define STORE_SYSREG(v, name) mcr CP32(v, name)
+
/* Issue a CP operation which takes no argument,
* uses r0 as a placeholder register. */
#define CMD_CP32(name...) "mcr " __stringify(CP32(r0, name)) ";"
@@ -1,6 +1,10 @@
#ifndef __ASM_ARM_CPREGS_H
#define __ASM_ARM_CPREGS_H
+#ifdef CONFIG_MPU
+#include <asm/mpu/cpregs.h>
+#endif
+
/*
* AArch32 Co-processor registers.
*
new file mode 100644
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __ASM_ARM_MPU_CPREGS_H
+#define __ASM_ARM_MPU_CPREGS_H
+
+#define HMPUIR p15,4,c0,c0,4
+
+/* CP15 CR6: MPU Protection Region Base/Limit/Select Address Register */
+#define HPRSELR p15,4,c6,c2,1
+#define PRBAR_EL2 p15,4,c6,c3,0
+#define PRLAR_EL2 p15,4,c6,c8,1
+
+#define MPUIR_EL2 HMPUIR
+#define PRSELR_EL2 HPRSELR
+
+#endif /* __ASM_ARM_MPU_CPREGS_H */
+
+/*
+ * Local variables:
+ * mode: ASM
+ * indent-tabs-mode: nil
+ * End:
+ */
We have created the same boot-time MPU protection regions as Armv8-R AArch64. Also, we have defined REGION_* macros for arm32. The only difference from arm64 is that XN is 1-bit for arm32. The macros have been defined in arm32/sysregs.h. Though REGION_NORMAL_PRLAR and REGION_DEVICE_PRLAR are same between arm32 and arm64, we have duplicated them to keep the definitions at the same place as the other REGION_* macros. Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com> --- Changes from v1 - 1. enable_mpu() now sets HMAIR{0,1} registers. This is similar to what is being done in enable_mmu(). All the mm related configurations happen in this function. 2. Fixed some typos. v2 - 1. Include the common prepare_xen_region.inc in head.S. 2. Define LOAD_SYSREG()/STORE_SYSREG() for arm32. xen/arch/arm/arm32/Makefile | 1 + xen/arch/arm/arm32/mpu/Makefile | 1 + xen/arch/arm/arm32/mpu/head.S | 52 ++++++++++++++++++++++++ xen/arch/arm/include/asm/arm32/sysregs.h | 11 +++++ xen/arch/arm/include/asm/cpregs.h | 4 ++ xen/arch/arm/include/asm/mpu/cpregs.h | 23 +++++++++++ 6 files changed, 92 insertions(+) create mode 100644 xen/arch/arm/arm32/mpu/Makefile create mode 100644 xen/arch/arm/arm32/mpu/head.S create mode 100644 xen/arch/arm/include/asm/mpu/cpregs.h