MIPS: Add MSA register definitions & access
This patch introduces definitions for the MSA control registers and
functions which allow access to both the control & vector registers. If
the toolchain being used to build the kernel includes support for MSA
then this patch will make use of that support & use MSA instructions
directly. However toolchain support for MSA is very new & far from a
point where it can be reasonably expected that everyone building the
kernel uses a toolchain with support. Thus fallbacks using .word
assembler directives are also provided for now as a temporary measure.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6429/
Patchwork: https://patchwork.linux-mips.org/patch/6607/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/msa.h b/arch/mips/include/asm/msa.h
new file mode 100644
index 0000000..0a614fb
--- /dev/null
+++ b/arch/mips/include/asm/msa.h
@@ -0,0 +1,175 @@
+/*
+ * Copyright (C) 2013 Imagination Technologies
+ * Author: Paul Burton <paul.burton@imgtec.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+#ifndef _ASM_MSA_H
+#define _ASM_MSA_H
+
+#include <asm/mipsregs.h>
+
+static inline void enable_msa(void)
+{
+ if (cpu_has_msa) {
+ set_c0_config5(MIPS_CONF5_MSAEN);
+ enable_fpu_hazard();
+ }
+}
+
+static inline void disable_msa(void)
+{
+ if (cpu_has_msa) {
+ clear_c0_config5(MIPS_CONF5_MSAEN);
+ disable_fpu_hazard();
+ }
+}
+
+static inline int is_msa_enabled(void)
+{
+ if (!cpu_has_msa)
+ return 0;
+
+ return read_c0_config5() & MIPS_CONF5_MSAEN;
+}
+
+#ifdef TOOLCHAIN_SUPPORTS_MSA
+
+#define __BUILD_MSA_CTL_REG(name, cs) \
+static inline unsigned int read_msa_##name(void) \
+{ \
+ unsigned int reg; \
+ __asm__ __volatile__( \
+ " .set push\n" \
+ " .set msa\n" \
+ " cfcmsa %0, $" #cs "\n" \
+ " .set pop\n" \
+ : "=r"(reg)); \
+ return reg; \
+} \
+ \
+static inline void write_msa_##name(unsigned int val) \
+{ \
+ __asm__ __volatile__( \
+ " .set push\n" \
+ " .set msa\n" \
+ " cfcmsa $" #cs ", %0\n" \
+ " .set pop\n" \
+ : : "r"(val)); \
+}
+
+#else /* !TOOLCHAIN_SUPPORTS_MSA */
+
+/*
+ * Define functions using .word for the c[ft]cmsa instructions in order to
+ * allow compilation with toolchains that do not support MSA. Once all
+ * toolchains in use support MSA these can be removed.
+ */
+
+#define __BUILD_MSA_CTL_REG(name, cs) \
+static inline unsigned int read_msa_##name(void) \
+{ \
+ unsigned int reg; \
+ __asm__ __volatile__( \
+ " .set push\n" \
+ " .set noat\n" \
+ " .word 0x787e0059 | (" #cs " << 11)\n" \
+ " move %0, $1\n" \
+ " .set pop\n" \
+ : "=r"(reg)); \
+ return reg; \
+} \
+ \
+static inline void write_msa_##name(unsigned int val) \
+{ \
+ __asm__ __volatile__( \
+ " .set push\n" \
+ " .set noat\n" \
+ " move $1, %0\n" \
+ " .word 0x783e0819 | (" #cs " << 6)\n" \
+ " .set pop\n" \
+ : : "r"(val)); \
+}
+
+#endif /* !TOOLCHAIN_SUPPORTS_MSA */
+
+#define MSA_IR 0
+#define MSA_CSR 1
+#define MSA_ACCESS 2
+#define MSA_SAVE 3
+#define MSA_MODIFY 4
+#define MSA_REQUEST 5
+#define MSA_MAP 6
+#define MSA_UNMAP 7
+
+__BUILD_MSA_CTL_REG(ir, 0)
+__BUILD_MSA_CTL_REG(csr, 1)
+__BUILD_MSA_CTL_REG(access, 2)
+__BUILD_MSA_CTL_REG(save, 3)
+__BUILD_MSA_CTL_REG(modify, 4)
+__BUILD_MSA_CTL_REG(request, 5)
+__BUILD_MSA_CTL_REG(map, 6)
+__BUILD_MSA_CTL_REG(unmap, 7)
+
+/* MSA Implementation Register (MSAIR) */
+#define MSA_IR_REVB 0
+#define MSA_IR_REVF (_ULCAST_(0xff) << MSA_IR_REVB)
+#define MSA_IR_PROCB 8
+#define MSA_IR_PROCF (_ULCAST_(0xff) << MSA_IR_PROCB)
+#define MSA_IR_WRPB 16
+#define MSA_IR_WRPF (_ULCAST_(0x1) << MSA_IR_WRPB)
+
+/* MSA Control & Status Register (MSACSR) */
+#define MSA_CSR_RMB 0
+#define MSA_CSR_RMF (_ULCAST_(0x3) << MSA_CSR_RMB)
+#define MSA_CSR_RM_NEAREST 0
+#define MSA_CSR_RM_TO_ZERO 1
+#define MSA_CSR_RM_TO_POS 2
+#define MSA_CSR_RM_TO_NEG 3
+#define MSA_CSR_FLAGSB 2
+#define MSA_CSR_FLAGSF (_ULCAST_(0x1f) << MSA_CSR_FLAGSB)
+#define MSA_CSR_FLAGS_IB 2
+#define MSA_CSR_FLAGS_IF (_ULCAST_(0x1) << MSA_CSR_FLAGS_IB)
+#define MSA_CSR_FLAGS_UB 3
+#define MSA_CSR_FLAGS_UF (_ULCAST_(0x1) << MSA_CSR_FLAGS_UB)
+#define MSA_CSR_FLAGS_OB 4
+#define MSA_CSR_FLAGS_OF (_ULCAST_(0x1) << MSA_CSR_FLAGS_OB)
+#define MSA_CSR_FLAGS_ZB 5
+#define MSA_CSR_FLAGS_ZF (_ULCAST_(0x1) << MSA_CSR_FLAGS_ZB)
+#define MSA_CSR_FLAGS_VB 6
+#define MSA_CSR_FLAGS_VF (_ULCAST_(0x1) << MSA_CSR_FLAGS_VB)
+#define MSA_CSR_ENABLESB 7
+#define MSA_CSR_ENABLESF (_ULCAST_(0x1f) << MSA_CSR_ENABLESB)
+#define MSA_CSR_ENABLES_IB 7
+#define MSA_CSR_ENABLES_IF (_ULCAST_(0x1) << MSA_CSR_ENABLES_IB)
+#define MSA_CSR_ENABLES_UB 8
+#define MSA_CSR_ENABLES_UF (_ULCAST_(0x1) << MSA_CSR_ENABLES_UB)
+#define MSA_CSR_ENABLES_OB 9
+#define MSA_CSR_ENABLES_OF (_ULCAST_(0x1) << MSA_CSR_ENABLES_OB)
+#define MSA_CSR_ENABLES_ZB 10
+#define MSA_CSR_ENABLES_ZF (_ULCAST_(0x1) << MSA_CSR_ENABLES_ZB)
+#define MSA_CSR_ENABLES_VB 11
+#define MSA_CSR_ENABLES_VF (_ULCAST_(0x1) << MSA_CSR_ENABLES_VB)
+#define MSA_CSR_CAUSEB 12
+#define MSA_CSR_CAUSEF (_ULCAST_(0x3f) << MSA_CSR_CAUSEB)
+#define MSA_CSR_CAUSE_IB 12
+#define MSA_CSR_CAUSE_IF (_ULCAST_(0x1) << MSA_CSR_CAUSE_IB)
+#define MSA_CSR_CAUSE_UB 13
+#define MSA_CSR_CAUSE_UF (_ULCAST_(0x1) << MSA_CSR_CAUSE_UB)
+#define MSA_CSR_CAUSE_OB 14
+#define MSA_CSR_CAUSE_OF (_ULCAST_(0x1) << MSA_CSR_CAUSE_OB)
+#define MSA_CSR_CAUSE_ZB 15
+#define MSA_CSR_CAUSE_ZF (_ULCAST_(0x1) << MSA_CSR_CAUSE_ZB)
+#define MSA_CSR_CAUSE_VB 16
+#define MSA_CSR_CAUSE_VF (_ULCAST_(0x1) << MSA_CSR_CAUSE_VB)
+#define MSA_CSR_CAUSE_EB 17
+#define MSA_CSR_CAUSE_EF (_ULCAST_(0x1) << MSA_CSR_CAUSE_EB)
+#define MSA_CSR_NXB 18
+#define MSA_CSR_NXF (_ULCAST_(0x1) << MSA_CSR_NXB)
+#define MSA_CSR_FSB 24
+#define MSA_CSR_FSF (_ULCAST_(0x1) << MSA_CSR_FSB)
+
+#endif /* _ASM_MSA_H */