arch/powerpc/include/asm/dcr-native.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * (c) Copyright 2006 Benjamin Herrenschmidt, IBM Corp.
   4  *                    <benh@kernel.crashing.org>
   5  */
   6
   7 #ifndef _ASM_POWERPC_DCR_NATIVE_H
   8 #define _ASM_POWERPC_DCR_NATIVE_H
   9 #ifdef __KERNEL__
  10 #ifndef __ASSEMBLY__
  11
  12 #include <linux/spinlock.h>
  13 #include <asm/cputable.h>
  14 #include <asm/cpu_has_feature.h>
  15 #include <linux/stringify.h>
  16
  17 typedef struct {
  18         unsigned int base;
  19 } dcr_host_native_t;
  20
  21 static inline bool dcr_map_ok_native(dcr_host_native_t host)
  22 {
  23         return true;
  24 }
  25
  26 #define dcr_map_native(dev, dcr_n, dcr_c) \
  27         ((dcr_host_native_t){ .base = (dcr_n) })
  28 #define dcr_unmap_native(host, dcr_c)           do {} while (0)
  29 #define dcr_read_native(host, dcr_n)            mfdcr(dcr_n + host.base)
  30 #define dcr_write_native(host, dcr_n, value)    mtdcr(dcr_n + host.base, value)
  31
  32 /* Table based DCR accessors */
  33 extern void __mtdcr(unsigned int reg, unsigned int val);
  34 extern unsigned int __mfdcr(unsigned int reg);
  35
  36 /* mfdcrx/mtdcrx instruction based accessors. We hand code
  37  * the opcodes in order not to depend on newer binutils
  38  */
  39 static inline unsigned int mfdcrx(unsigned int reg)
  40 {
  41         unsigned int ret;
  42         asm volatile(".long 0x7c000206 | (%0 << 21) | (%1 << 16)"
  43                      : "=r" (ret) : "r" (reg));
  44         return ret;
  45 }
  46
  47 static inline void mtdcrx(unsigned int reg, unsigned int val)
  48 {
  49         asm volatile(".long 0x7c000306 | (%0 << 21) | (%1 << 16)"
  50                      : : "r" (val), "r" (reg));
  51 }
  52
  53 #define mfdcr(rn)                                               \
  54         ({unsigned int rval;                                    \
  55         if (__builtin_constant_p(rn) && rn < 1024)              \
  56                 asm volatile("mfdcr %0," __stringify(rn)        \
  57                               : "=r" (rval));                   \
  58         else if (likely(cpu_has_feature(CPU_FTR_INDEXED_DCR)))  \
  59                 rval = mfdcrx(rn);                              \
  60         else                                                    \
  61                 rval = __mfdcr(rn);                             \
  62         rval;})
  63
  64 #define mtdcr(rn, v)                                            \
  65 do {                                                            \
  66         if (__builtin_constant_p(rn) && rn < 1024)              \
  67                 asm volatile("mtdcr " __stringify(rn) ",%0"     \
  68                               : : "r" (v));                     \
  69         else if (likely(cpu_has_feature(CPU_FTR_INDEXED_DCR)))  \
  70                 mtdcrx(rn, v);                                  \
  71         else                                                    \
  72                 __mtdcr(rn, v);                                 \
  73 } while (0)
  74
  75 /* R/W of indirect DCRs make use of standard naming conventions for DCRs */
  76 extern spinlock_t dcr_ind_lock;
  77
  78 static inline unsigned __mfdcri(int base_addr, int base_data, int reg)
  79 {
  80         unsigned long flags;
  81         unsigned int val;
  82
  83         spin_lock_irqsave(&dcr_ind_lock, flags);
  84         if (cpu_has_feature(CPU_FTR_INDEXED_DCR)) {
  85                 mtdcrx(base_addr, reg);
  86                 val = mfdcrx(base_data);
  87         } else {
  88                 __mtdcr(base_addr, reg);
  89                 val = __mfdcr(base_data);
  90         }
  91         spin_unlock_irqrestore(&dcr_ind_lock, flags);
  92         return val;
  93 }
  94
  95 static inline void __mtdcri(int base_addr, int base_data, int reg,
  96                             unsigned val)
  97 {
  98         unsigned long flags;
  99
 100         spin_lock_irqsave(&dcr_ind_lock, flags);
 101         if (cpu_has_feature(CPU_FTR_INDEXED_DCR)) {
 102                 mtdcrx(base_addr, reg);
 103                 mtdcrx(base_data, val);
 104         } else {
 105                 __mtdcr(base_addr, reg);
 106                 __mtdcr(base_data, val);
 107         }
 108         spin_unlock_irqrestore(&dcr_ind_lock, flags);
 109 }
 110
 111 static inline void __dcri_clrset(int base_addr, int base_data, int reg,
 112                                  unsigned clr, unsigned set)
 113 {
 114         unsigned long flags;
 115         unsigned int val;
 116
 117         spin_lock_irqsave(&dcr_ind_lock, flags);
 118         if (cpu_has_feature(CPU_FTR_INDEXED_DCR)) {
 119                 mtdcrx(base_addr, reg);
 120                 val = (mfdcrx(base_data) & ~clr) | set;
 121                 mtdcrx(base_data, val);
 122         } else {
 123                 __mtdcr(base_addr, reg);
 124                 val = (__mfdcr(base_data) & ~clr) | set;
 125                 __mtdcr(base_data, val);
 126         }
 127         spin_unlock_irqrestore(&dcr_ind_lock, flags);
 128 }
 129
 130 #define mfdcri(base, reg)       __mfdcri(DCRN_ ## base ## _CONFIG_ADDR, \
 131                                          DCRN_ ## base ## _CONFIG_DATA, \
 132                                          reg)
 133
 134 #define mtdcri(base, reg, data) __mtdcri(DCRN_ ## base ## _CONFIG_ADDR, \
 135                                          DCRN_ ## base ## _CONFIG_DATA, \
 136                                          reg, data)
 137
 138 #define dcri_clrset(base, reg, clr, set)        __dcri_clrset(DCRN_ ## base ## _CONFIG_ADDR,    \
 139                                                               DCRN_ ## base ## _CONFIG_DATA,    \
 140                                                               reg, clr, set)
 141
 142 #endif /* __ASSEMBLY__ */
 143 #endif /* __KERNEL__ */
 144 #endif /* _ASM_POWERPC_DCR_NATIVE_H */