platforms/pseries/hvCall.S

0001 /* SPDX-License-Identifier: GPL-2.0-or-later */
0002 /*
0003  * This file contains the generic code to perform a call to the
0004  * pSeries LPAR hypervisor.
0005  */
0006 #include <linux/jump_label.h>
0007 #include <asm/hvcall.h>
0008 #include <asm/processor.h>
0009 #include <asm/ppc_asm.h>
0010 #include <asm/asm-offsets.h>
0011 #include <asm/ptrace.h>
0012 #include <asm/feature-fixups.h>
0013
0014     .section    ".text"
0015
0016 #ifdef CONFIG_TRACEPOINTS
0017
0018 #ifndef CONFIG_JUMP_LABEL
0019     .section    ".toc","aw"
0020
0021     .globl hcall_tracepoint_refcount
0022 hcall_tracepoint_refcount:
0023     .8byte  0
0024
0025     .section    ".text"
0026 #endif
0027
0028 /*
0029  * precall must preserve all registers.  use unused STK_PARAM()
0030  * areas to save snapshots and opcode.
0031  */
0032 #define HCALL_INST_PRECALL(FIRST_REG)               \
0033     mflr    r0;                     \
0034     std r3,STK_PARAM(R3)(r1);               \
0035     std r4,STK_PARAM(R4)(r1);               \
0036     std r5,STK_PARAM(R5)(r1);               \
0037     std r6,STK_PARAM(R6)(r1);               \
0038     std r7,STK_PARAM(R7)(r1);               \
0039     std r8,STK_PARAM(R8)(r1);               \
0040     std r9,STK_PARAM(R9)(r1);               \
0041     std r10,STK_PARAM(R10)(r1);             \
0042     std r0,16(r1);                  \
0043     addi    r4,r1,STK_PARAM(FIRST_REG);         \
0044     stdu    r1,-STACK_FRAME_OVERHEAD(r1);           \
0045     bl  __trace_hcall_entry;                \
0046     ld  r3,STACK_FRAME_OVERHEAD+STK_PARAM(R3)(r1);  \
0047     ld  r4,STACK_FRAME_OVERHEAD+STK_PARAM(R4)(r1);  \
0048     ld  r5,STACK_FRAME_OVERHEAD+STK_PARAM(R5)(r1);  \
0049     ld  r6,STACK_FRAME_OVERHEAD+STK_PARAM(R6)(r1);  \
0050     ld  r7,STACK_FRAME_OVERHEAD+STK_PARAM(R7)(r1);  \
0051     ld  r8,STACK_FRAME_OVERHEAD+STK_PARAM(R8)(r1);  \
0052     ld  r9,STACK_FRAME_OVERHEAD+STK_PARAM(R9)(r1);  \
0053     ld  r10,STACK_FRAME_OVERHEAD+STK_PARAM(R10)(r1)
0054
0055 /*
0056  * postcall is performed immediately before function return which
0057  * allows liberal use of volatile registers.
0058  */
0059 #define __HCALL_INST_POSTCALL                   \
0060     ld  r0,STACK_FRAME_OVERHEAD+STK_PARAM(R3)(r1);  \
0061     std r3,STACK_FRAME_OVERHEAD+STK_PARAM(R3)(r1);  \
0062     mr  r4,r3;                      \
0063     mr  r3,r0;                      \
0064     bl  __trace_hcall_exit;             \
0065     ld  r0,STACK_FRAME_OVERHEAD+16(r1);         \
0066     addi    r1,r1,STACK_FRAME_OVERHEAD;         \
0067     ld  r3,STK_PARAM(R3)(r1);               \
0068     mtlr    r0
0069
0070 #define HCALL_INST_POSTCALL_NORETS              \
0071     li  r5,0;                       \
0072     __HCALL_INST_POSTCALL
0073
0074 #define HCALL_INST_POSTCALL(BUFREG)             \
0075     mr  r5,BUFREG;                  \
0076     __HCALL_INST_POSTCALL
0077
0078 #ifdef CONFIG_JUMP_LABEL
0079 #define HCALL_BRANCH(LABEL)                 \
0080     ARCH_STATIC_BRANCH(LABEL, hcall_tracepoint_key)
0081 #else
0082
0083 /*
0084  * We branch around this in early init (eg when populating the MMU
0085  * hashtable) by using an unconditional cpu feature.
0086  */
0087 #define HCALL_BRANCH(LABEL)                 \
0088 BEGIN_FTR_SECTION;                      \
0089     b   1f;                     \
0090 END_FTR_SECTION(0, 1);                      \
0091     ld  r12,hcall_tracepoint_refcount@toc(r2);      \
0092     std r12,32(r1);                 \
0093     cmpdi   r12,0;                      \
0094     bne-    LABEL;                      \
0095 1:
0096 #endif
0097
0098 #else
0099 #define HCALL_INST_PRECALL(FIRST_ARG)
0100 #define HCALL_INST_POSTCALL_NORETS
0101 #define HCALL_INST_POSTCALL(BUFREG)
0102 #define HCALL_BRANCH(LABEL)
0103 #endif
0104
0105 _GLOBAL_TOC(plpar_hcall_norets_notrace)
0106     HMT_MEDIUM
0107
0108     mfcr    r0
0109     stw r0,8(r1)
0110     HVSC                /* invoke the hypervisor */
0111
0112     li  r4,0
0113     stb r4,PACASRR_VALID(r13)
0114
0115     lwz r0,8(r1)
0116     mtcrf   0xff,r0
0117     blr             /* return r3 = status */
0118
0119 _GLOBAL_TOC(plpar_hcall_norets)
0120     HMT_MEDIUM
0121
0122     mfcr    r0
0123     stw r0,8(r1)
0124     HCALL_BRANCH(plpar_hcall_norets_trace)
0125     HVSC                /* invoke the hypervisor */
0126
0127     li  r4,0
0128     stb r4,PACASRR_VALID(r13)
0129
0130     lwz r0,8(r1)
0131     mtcrf   0xff,r0
0132     blr             /* return r3 = status */
0133
0134 #ifdef CONFIG_TRACEPOINTS
0135 plpar_hcall_norets_trace:
0136     HCALL_INST_PRECALL(R4)
0137     HVSC
0138     HCALL_INST_POSTCALL_NORETS
0139
0140     li  r4,0
0141     stb r4,PACASRR_VALID(r13)
0142
0143     lwz r0,8(r1)
0144     mtcrf   0xff,r0
0145     blr
0146 #endif
0147
0148 _GLOBAL_TOC(plpar_hcall)
0149     HMT_MEDIUM
0150
0151     mfcr    r0
0152     stw r0,8(r1)
0153
0154     HCALL_BRANCH(plpar_hcall_trace)
0155
0156     std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */
0157
0158     mr  r4,r5
0159     mr  r5,r6
0160     mr  r6,r7
0161     mr  r7,r8
0162     mr  r8,r9
0163     mr  r9,r10
0164
0165     HVSC                /* invoke the hypervisor */
0166
0167     ld  r12,STK_PARAM(R4)(r1)
0168     std r4,  0(r12)
0169     std r5,  8(r12)
0170     std r6, 16(r12)
0171     std r7, 24(r12)
0172
0173     li  r4,0
0174     stb r4,PACASRR_VALID(r13)
0175
0176     lwz r0,8(r1)
0177     mtcrf   0xff,r0
0178
0179     blr             /* return r3 = status */
0180
0181 #ifdef CONFIG_TRACEPOINTS
0182 plpar_hcall_trace:
0183     HCALL_INST_PRECALL(R5)
0184
0185     std r4,STK_PARAM(R4)(r1)
0186     mr  r0,r4
0187
0188     mr  r4,r5
0189     mr  r5,r6
0190     mr  r6,r7
0191     mr  r7,r8
0192     mr  r8,r9
0193     mr  r9,r10
0194
0195     HVSC
0196
0197     ld  r12,STK_PARAM(R4)(r1)
0198     std r4,0(r12)
0199     std r5,8(r12)
0200     std r6,16(r12)
0201     std r7,24(r12)
0202
0203     HCALL_INST_POSTCALL(r12)
0204
0205     li  r4,0
0206     stb r4,PACASRR_VALID(r13)
0207
0208     lwz r0,8(r1)
0209     mtcrf   0xff,r0
0210
0211     blr
0212 #endif
0213
0214 /*
0215  * plpar_hcall_raw can be called in real mode. kexec/kdump need some
0216  * hypervisor calls to be executed in real mode. So plpar_hcall_raw
0217  * does not access the per cpu hypervisor call statistics variables,
0218  * since these variables may not be present in the RMO region.
0219  */
0220 _GLOBAL(plpar_hcall_raw)
0221     HMT_MEDIUM
0222
0223     mfcr    r0
0224     stw r0,8(r1)
0225
0226     std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */
0227
0228     mr  r4,r5
0229     mr  r5,r6
0230     mr  r6,r7
0231     mr  r7,r8
0232     mr  r8,r9
0233     mr  r9,r10
0234
0235     HVSC                /* invoke the hypervisor */
0236
0237     ld  r12,STK_PARAM(R4)(r1)
0238     std r4,  0(r12)
0239     std r5,  8(r12)
0240     std r6, 16(r12)
0241     std r7, 24(r12)
0242
0243     li  r4,0
0244     stb r4,PACASRR_VALID(r13)
0245
0246     lwz r0,8(r1)
0247     mtcrf   0xff,r0
0248
0249     blr             /* return r3 = status */
0250
0251 _GLOBAL_TOC(plpar_hcall9)
0252     HMT_MEDIUM
0253
0254     mfcr    r0
0255     stw r0,8(r1)
0256
0257     HCALL_BRANCH(plpar_hcall9_trace)
0258
0259     std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */
0260
0261     mr  r4,r5
0262     mr  r5,r6
0263     mr  r6,r7
0264     mr  r7,r8
0265     mr  r8,r9
0266     mr  r9,r10
0267     ld  r10,STK_PARAM(R11)(r1)   /* put arg7 in R10 */
0268     ld  r11,STK_PARAM(R12)(r1)   /* put arg8 in R11 */
0269     ld  r12,STK_PARAM(R13)(r1)    /* put arg9 in R12 */
0270
0271     HVSC                /* invoke the hypervisor */
0272
0273     mr  r0,r12
0274     ld  r12,STK_PARAM(R4)(r1)
0275     std r4,  0(r12)
0276     std r5,  8(r12)
0277     std r6, 16(r12)
0278     std r7, 24(r12)
0279     std r8, 32(r12)
0280     std r9, 40(r12)
0281     std r10,48(r12)
0282     std r11,56(r12)
0283     std r0, 64(r12)
0284
0285     li  r4,0
0286     stb r4,PACASRR_VALID(r13)
0287
0288     lwz r0,8(r1)
0289     mtcrf   0xff,r0
0290
0291     blr             /* return r3 = status */
0292
0293 #ifdef CONFIG_TRACEPOINTS
0294 plpar_hcall9_trace:
0295     HCALL_INST_PRECALL(R5)
0296
0297     std r4,STK_PARAM(R4)(r1)
0298     mr  r0,r4
0299
0300     mr  r4,r5
0301     mr  r5,r6
0302     mr  r6,r7
0303     mr  r7,r8
0304     mr  r8,r9
0305     mr  r9,r10
0306     ld  r10,STACK_FRAME_OVERHEAD+STK_PARAM(R11)(r1)
0307     ld  r11,STACK_FRAME_OVERHEAD+STK_PARAM(R12)(r1)
0308     ld  r12,STACK_FRAME_OVERHEAD+STK_PARAM(R13)(r1)
0309
0310     HVSC
0311
0312     mr  r0,r12
0313     ld  r12,STACK_FRAME_OVERHEAD+STK_PARAM(R4)(r1)
0314     std r4,0(r12)
0315     std r5,8(r12)
0316     std r6,16(r12)
0317     std r7,24(r12)
0318     std r8,32(r12)
0319     std r9,40(r12)
0320     std r10,48(r12)
0321     std r11,56(r12)
0322     std r0,64(r12)
0323
0324     HCALL_INST_POSTCALL(r12)
0325
0326     li  r4,0
0327     stb r4,PACASRR_VALID(r13)
0328
0329     lwz r0,8(r1)
0330     mtcrf   0xff,r0
0331
0332     blr
0333 #endif
0334
0335 /* See plpar_hcall_raw to see why this is needed */
0336 _GLOBAL(plpar_hcall9_raw)
0337     HMT_MEDIUM
0338
0339     mfcr    r0
0340     stw r0,8(r1)
0341
0342     std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */
0343
0344     mr  r4,r5
0345     mr  r5,r6
0346     mr  r6,r7
0347     mr  r7,r8
0348     mr  r8,r9
0349     mr  r9,r10
0350     ld  r10,STK_PARAM(R11)(r1)   /* put arg7 in R10 */
0351     ld  r11,STK_PARAM(R12)(r1)   /* put arg8 in R11 */
0352     ld  r12,STK_PARAM(R13)(r1)    /* put arg9 in R12 */
0353
0354     HVSC                /* invoke the hypervisor */
0355
0356     mr  r0,r12
0357     ld  r12,STK_PARAM(R4)(r1)
0358     std r4,  0(r12)
0359     std r5,  8(r12)
0360     std r6, 16(r12)
0361     std r7, 24(r12)
0362     std r8, 32(r12)
0363     std r9, 40(r12)
0364     std r10,48(r12)
0365     std r11,56(r12)
0366     std r0, 64(r12)
0367
0368     li  r4,0
0369     stb r4,PACASRR_VALID(r13)
0370
0371     lwz r0,8(r1)
0372     mtcrf   0xff,r0
0373
0374     blr             /* return r3 = status */