[xen master] xen/riscv: add minimal stuff to processor.h to build full Xen

[patchbot@xxxxxxx]

commit d654612e985297fe745f3260295ffd34f5b01b2d
Author:     Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
AuthorDate: Mon Mar 25 10:47:49 2024 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Mar 25 10:47:49 2024 +0100

    xen/riscv: add minimal stuff to processor.h to build full Xen
    
    The cpu_relax() function, introduced in this commit, is anticipated to
    support _zihintpause by the CPU.
    
    Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
    Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/arch/riscv/include/asm/processor.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/xen/arch/riscv/include/asm/processor.h 
b/xen/arch/riscv/include/asm/processor.h
index 6db681d805..6846151717 100644
--- a/xen/arch/riscv/include/asm/processor.h
+++ b/xen/arch/riscv/include/asm/processor.h
@@ -12,6 +12,9 @@
 
 #ifndef __ASSEMBLY__
 
+/* TODO: need to be implemeted */
+#define smp_processor_id() 0
+
 /* On stack VCPU state */
 struct cpu_user_regs
 {
@@ -53,6 +56,23 @@ struct cpu_user_regs
     unsigned long pregs;
 };
 
+/* TODO: need to implement */
+#define cpu_to_core(cpu)   0
+#define cpu_to_socket(cpu) 0
+
+static inline void cpu_relax(void)
+{
+#ifdef __riscv_zihintpause
+    /* Reduce instruction retirement. */
+    __asm__ __volatile__ ( "pause" );
+#else
+    /* Encoding of the pause instruction */
+    __asm__ __volatile__ ( ".insn 0x0100000F" );
+#endif
+
+    barrier();
+}
+
 static inline void wfi(void)
 {
     __asm__ __volatile__ ("wfi");
--
generated by git-patchbot for /home/xen/git/xen.git#master