The ARM32 has PLx Privilege Levels instead of Exception Levels present
on ARM64. Introduce current_pl() function which reports the current PL
on ARM32.
Introduce current_el() for ARM32 as well and current_pl() for ARM64
which each call the other matching function. This is mainly mean to
allow code like this to compile and retain compile time code coverage:
if (IS_ENABLED(CONFIG_ARM64) && current_el() != 3) { ... }
if (!IS_ENABLED(CONFIG_ARM64) && current_pl() != 0) { ... }
Signed-off-by: Marek Vasut <[email protected]>
---
Cc: Ilias Apalodimas <[email protected]>
Cc: Jerome Forissier <[email protected]>
Cc: Tom Rini <[email protected]>
Cc: [email protected]
---
arch/arm/include/asm/system.h | 39 +++++++++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)
diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h
index 4c1b81483c9..9e3ad57073d 100644
--- a/arch/arm/include/asm/system.h
+++ b/arch/arm/include/asm/system.h
@@ -171,6 +171,12 @@ static inline unsigned int current_el(void)
return 3 & (el >> 2);
}
+static inline unsigned int current_pl(void)
+{
+ /* Aarch32 compatibility */
+ return current_el();
+};
+
static inline unsigned long get_sctlr(void)
{
unsigned int el;
@@ -466,6 +472,39 @@ static inline int is_hyp(void)
#endif
}
+static inline int is_usr(void)
+{
+ return (get_cpsr() & 0x1f) == 0x10;
+}
+
+static inline unsigned int current_pl(void)
+{
+ /*
+ * ARM DDI 0406C.d ID040418 , page 140 chapter A3.6.1 "Processor
+ * privilege levels, execution privilege, and access privilege",
+ * clarifies the PLx levels as follows (abbreviated):
+ * The characteristics of the privilege levels are:
+ * - PL0 - The privilege level of application software, that
+ * executes in User mode.
+ * - PL1 - Software execution in all modes other than User mode
+ * and Hyp mode is at PL1.
+ * - PL2 - Software executing in Hyp mode executes at PL2.
+ */
+ if (is_hyp()) /* HYP */
+ return 2;
+
+ if (is_usr()) /* USR */
+ return 0;
+
+ return 1; /* The rest */
+}
+
+static inline unsigned int current_el(void)
+{
+ /* Aarch64 compatibility */
+ return current_pl();
+};
+
static inline unsigned int get_cr(void)
{
unsigned int val;
--
2.51.0
