xen/riscv: add <asm/csr.h> header

The following changes were made in comparison with <asm/csr.h> from
Linux:
  * remove all defines as they are defined in riscv_encoding.h
  * leave only csr_* macros

Origin: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ d2d11f342b17
Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

diff --git a/xen/arch/riscv/include/asm/csr.h b/xen/arch/riscv/include/asm/csr.h
new file mode 100644 (file)
index 0000000..8215562
--- /dev/null
+++ b/xen/arch/riscv/include/asm/csr.h
@@ -0,0 +1,84 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (C) 2015 Regents of the University of California
+ */
+
+#ifndef _ASM_RISCV_CSR_H
+#define _ASM_RISCV_CSR_H
+
+#include <asm/asm.h>
+#include <xen/const.h>
+#include <asm/riscv_encoding.h>
+
+#ifndef __ASSEMBLY__
+
+#define csr_read(csr)                                           \
+({                                                              \
+    register unsigned long __v;                                 \
+    __asm__ __volatile__ ( "csrr %0, " __ASM_STR(csr)           \
+                           : "=r" (__v)                         \
+                           : : "memory" );                      \
+    __v;                                                        \
+})
+
+#define csr_write(csr, val)                                     \
+({                                                              \
+    unsigned long __v = (unsigned long)(val);                   \
+    __asm__ __volatile__ ( "csrw " __ASM_STR(csr) ", %0"        \
+                           : /* no outputs */                   \
+                           : "rK" (__v)                         \
+                           : "memory" );                        \
+})
+
+#define csr_swap(csr, val)                                      \
+({                                                              \
+    unsigned long __v = (unsigned long)(val);                   \
+    __asm__ __volatile__ ( "csrrw %0, " __ASM_STR(csr) ", %1"   \
+                           : "=r" (__v)                         \
+                           : "rK" (__v)                         \
+                           : "memory" );                        \
+    __v;                                                        \
+})
+
+#define csr_read_set(csr, val)                                  \
+({                                                              \
+    unsigned long __v = (unsigned long)(val);                   \
+    __asm__ __volatile__ ( "csrrs %0, " __ASM_STR(csr) ", %1"   \
+                           : "=r" (__v)                         \
+                           : "rK" (__v)                         \
+                           : "memory" );                        \
+    __v;                                                        \
+})
+
+#define csr_set(csr, val)                                       \
+({                                                              \
+    unsigned long __v = (unsigned long)(val);                   \
+    __asm__ __volatile__ ( "csrs " __ASM_STR(csr) ", %0"        \
+                           : /* no outputs */                   \
+                           : "rK" (__v)                         \
+                           : "memory" );                        \
+})
+
+#define csr_read_clear(csr, val)                                \
+({                                                              \
+    unsigned long __v = (unsigned long)(val);                   \
+    __asm__ __volatile__ ( "csrrc %0, " __ASM_STR(csr) ", %1"   \
+                           : "=r" (__v)                         \
+                           : "rK" (__v)                         \
+                           : "memory" );                        \
+    __v;                                                        \
+})
+
+#define csr_clear(csr, val)                                     \
+({                                                              \
+    unsigned long __v = (unsigned long)(val);                   \
+    __asm__ __volatile__ ( "csrc " __ASM_STR(csr) ", %0"        \
+                           : /* no outputs */                   \
+                           : "rK" (__v)                         \
+                           : "memory" );                        \
+})
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_CSR_H */