arch/mips/include/asm/mach-loongson64/cpucfg-emul.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_MACH_LOONGSON64_CPUCFG_EMUL_H_
   3 #define _ASM_MACH_LOONGSON64_CPUCFG_EMUL_H_
   4
   5 #include <asm/cpu-info.h>
   6
   7 #ifdef CONFIG_CPU_LOONGSON3_CPUCFG_EMULATION
   8
   9 #include <loongson_regs.h>
  10
  11 #define LOONGSON_FPREV_MASK 0x7
  12
  13 void loongson3_cpucfg_synthesize_data(struct cpuinfo_mips *c);
  14
  15 static inline bool loongson3_cpucfg_emulation_enabled(struct cpuinfo_mips *c)
  16 {
  17         /* All supported cores have non-zero LOONGSON_CFG1 data. */
  18         return c->loongson3_cpucfg_data[0] != 0;
  19 }
  20
  21 static inline u32 loongson3_cpucfg_read_synthesized(struct cpuinfo_mips *c,
  22         __u64 sel)
  23 {
  24         switch (sel) {
  25         case LOONGSON_CFG0:
  26                 return c->processor_id;
  27         case LOONGSON_CFG1:
  28         case LOONGSON_CFG2:
  29         case LOONGSON_CFG3:
  30                 return c->loongson3_cpucfg_data[sel - 1];
  31         case LOONGSON_CFG4:
  32         case LOONGSON_CFG5:
  33                 /* CPUCFG selects 4 and 5 are related to the input clock
  34                  * signal.
  35                  *
  36                  * Unimplemented for now.
  37                  */
  38                 return 0;
  39         case LOONGSON_CFG6:
  40                 /* CPUCFG select 6 is for the undocumented Safe Extension. */
  41                 return 0;
  42         case LOONGSON_CFG7:
  43                 /* CPUCFG select 7 is for the virtualization extension.
  44                  * We don't know if the two currently known features are
  45                  * supported on older cores according to the public
  46                  * documentation, so leave this at zero.
  47                  */
  48                 return 0;
  49         }
  50
  51         /*
  52          * Return 0 for unrecognized CPUCFG selects, which is real hardware
  53          * behavior observed on Loongson 3A R4.
  54          */
  55         return 0;
  56 }
  57 #else
  58 static inline void loongson3_cpucfg_synthesize_data(struct cpuinfo_mips *c)
  59 {
  60 }
  61
  62 static inline bool loongson3_cpucfg_emulation_enabled(struct cpuinfo_mips *c)
  63 {
  64         return false;
  65 }
  66
  67 static inline u32 loongson3_cpucfg_read_synthesized(struct cpuinfo_mips *c,
  68         __u64 sel)
  69 {
  70         return 0;
  71 }
  72 #endif
  73
  74 #endif /* _ASM_MACH_LOONGSON64_CPUCFG_EMUL_H_ */