diff --git a/Documentation/arm64/booting.rst b/Documentation/arm64/booting.rst index a3f1a47b6f1c..e50186092948 100644 --- a/Documentation/arm64/booting.rst +++ b/Documentation/arm64/booting.rst @@ -173,7 +173,9 @@ Before jumping into the kernel, the following conditions must be met: - Caches, MMUs The MMU must be off. + Instruction cache may be on or off. + The address range corresponding to the loaded kernel image must be cleaned to the PoC. In the presence of a system cache or other coherent masters with caches enabled, this will typically require @@ -238,6 +240,7 @@ Before jumping into the kernel, the following conditions must be met: - The DT or ACPI tables must describe a GICv2 interrupt controller. For CPUs with pointer authentication functionality: + - If EL3 is present: - SCR_EL3.APK (bit 16) must be initialised to 0b1 @@ -249,18 +252,22 @@ Before jumping into the kernel, the following conditions must be met: - HCR_EL2.API (bit 41) must be initialised to 0b1 For CPUs with Activity Monitors Unit v1 (AMUv1) extension present: + - If EL3 is present: - CPTR_EL3.TAM (bit 30) must be initialised to 0b0 - CPTR_EL2.TAM (bit 30) must be initialised to 0b0 - AMCNTENSET0_EL0 must be initialised to 0b1111 - AMCNTENSET1_EL0 must be initialised to a platform specific value - having 0b1 set for the corresponding bit for each of the auxiliary - counters present. + + - CPTR_EL3.TAM (bit 30) must be initialised to 0b0 + - CPTR_EL2.TAM (bit 30) must be initialised to 0b0 + - AMCNTENSET0_EL0 must be initialised to 0b1111 + - AMCNTENSET1_EL0 must be initialised to a platform specific value + having 0b1 set for the corresponding bit for each of the auxiliary + counters present. + - If the kernel is entered at EL1: - AMCNTENSET0_EL0 must be initialised to 0b1111 - AMCNTENSET1_EL0 must be initialised to a platform specific value - having 0b1 set for the corresponding bit for each of the auxiliary - counters present. + + - AMCNTENSET0_EL0 must be initialised to 0b1111 + - AMCNTENSET1_EL0 must be initialised to a platform specific value + having 0b1 set for the corresponding bit for each of the auxiliary + counters present. The requirements described above for CPU mode, caches, MMUs, architected timers, coherency and system registers apply to all CPUs. All CPUs must @@ -304,7 +311,8 @@ following manner: Documentation/devicetree/bindings/arm/psci.yaml. - Secondary CPU general-purpose register settings - x0 = 0 (reserved for future use) - x1 = 0 (reserved for future use) - x2 = 0 (reserved for future use) - x3 = 0 (reserved for future use) + + - x0 = 0 (reserved for future use) + - x1 = 0 (reserved for future use) + - x2 = 0 (reserved for future use) + - x3 = 0 (reserved for future use)