qemu/hw/spapr_hcall.c
David Gibson ed120055c7 Implement PAPR VPA functions for pSeries shared processor partitions
Shared-processor partitions are those where a CPU is time-sliced between
partitions, rather than being permanently dedicated to a single
partition.  qemu emulated partitions, since they are just scheduled with
the qemu user process, behave mostly like shared processor partitions.

In order to better support shared processor partitions (splpar), PAPR
defines the "VPA" (Virtual Processor Area), a shared memory communication
channel between the hypervisor and partitions.  There are also two
additional shared memory communication areas for specialized purposes
associated with the VPA.

A VPA is not essential for operating an splpar, though it can be necessary
for obtaining accurate performance measurements in the presence of
runtime partition switching.

Most importantly, however, the VPA is a prerequisite for PAPR's H_CEDE,
hypercall, which allows a partition OS to give up it's shared processor
timeslices to other partitions when idle.

This patch implements the VPA and H_CEDE hypercalls in qemu.  We don't
implement any of the more advanced statistics which can be communicated
through the VPA.  However, this is enough to make normal pSeries kernels
do an effective power-save idle on an emulated pSeries, significantly
reducing the host load of a qemu emulated pSeries running an idle guest OS.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-04-01 18:34:57 +02:00

526 lines
14 KiB
C

#include "sysemu.h"
#include "cpu.h"
#include "qemu-char.h"
#include "sysemu.h"
#include "qemu-char.h"
#include "exec-all.h"
#include "exec.h"
#include "helper_regs.h"
#include "hw/spapr.h"
#define HPTES_PER_GROUP 8
#define HPTE_V_SSIZE_SHIFT 62
#define HPTE_V_AVPN_SHIFT 7
#define HPTE_V_AVPN 0x3fffffffffffff80ULL
#define HPTE_V_AVPN_VAL(x) (((x) & HPTE_V_AVPN) >> HPTE_V_AVPN_SHIFT)
#define HPTE_V_COMPARE(x, y) (!(((x) ^ (y)) & 0xffffffffffffff80UL))
#define HPTE_V_BOLTED 0x0000000000000010ULL
#define HPTE_V_LOCK 0x0000000000000008ULL
#define HPTE_V_LARGE 0x0000000000000004ULL
#define HPTE_V_SECONDARY 0x0000000000000002ULL
#define HPTE_V_VALID 0x0000000000000001ULL
#define HPTE_R_PP0 0x8000000000000000ULL
#define HPTE_R_TS 0x4000000000000000ULL
#define HPTE_R_KEY_HI 0x3000000000000000ULL
#define HPTE_R_RPN_SHIFT 12
#define HPTE_R_RPN 0x3ffffffffffff000ULL
#define HPTE_R_FLAGS 0x00000000000003ffULL
#define HPTE_R_PP 0x0000000000000003ULL
#define HPTE_R_N 0x0000000000000004ULL
#define HPTE_R_G 0x0000000000000008ULL
#define HPTE_R_M 0x0000000000000010ULL
#define HPTE_R_I 0x0000000000000020ULL
#define HPTE_R_W 0x0000000000000040ULL
#define HPTE_R_WIMG 0x0000000000000078ULL
#define HPTE_R_C 0x0000000000000080ULL
#define HPTE_R_R 0x0000000000000100ULL
#define HPTE_R_KEY_LO 0x0000000000000e00ULL
#define HPTE_V_1TB_SEG 0x4000000000000000ULL
#define HPTE_V_VRMA_MASK 0x4001ffffff000000ULL
#define HPTE_V_HVLOCK 0x40ULL
static inline int lock_hpte(void *hpte, target_ulong bits)
{
uint64_t pteh;
pteh = ldq_p(hpte);
/* We're protected by qemu's global lock here */
if (pteh & bits) {
return 0;
}
stq_p(hpte, pteh | HPTE_V_HVLOCK);
return 1;
}
static target_ulong compute_tlbie_rb(target_ulong v, target_ulong r,
target_ulong pte_index)
{
target_ulong rb, va_low;
rb = (v & ~0x7fULL) << 16; /* AVA field */
va_low = pte_index >> 3;
if (v & HPTE_V_SECONDARY) {
va_low = ~va_low;
}
/* xor vsid from AVA */
if (!(v & HPTE_V_1TB_SEG)) {
va_low ^= v >> 12;
} else {
va_low ^= v >> 24;
}
va_low &= 0x7ff;
if (v & HPTE_V_LARGE) {
rb |= 1; /* L field */
#if 0 /* Disable that P7 specific bit for now */
if (r & 0xff000) {
/* non-16MB large page, must be 64k */
/* (masks depend on page size) */
rb |= 0x1000; /* page encoding in LP field */
rb |= (va_low & 0x7f) << 16; /* 7b of VA in AVA/LP field */
rb |= (va_low & 0xfe); /* AVAL field */
}
#endif
} else {
/* 4kB page */
rb |= (va_low & 0x7ff) << 12; /* remaining 11b of AVA */
}
rb |= (v >> 54) & 0x300; /* B field */
return rb;
}
static target_ulong h_enter(CPUState *env, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong flags = args[0];
target_ulong pte_index = args[1];
target_ulong pteh = args[2];
target_ulong ptel = args[3];
target_ulong porder;
target_ulong i, pa;
uint8_t *hpte;
/* only handle 4k and 16M pages for now */
porder = 12;
if (pteh & HPTE_V_LARGE) {
#if 0 /* We don't support 64k pages yet */
if ((ptel & 0xf000) == 0x1000) {
/* 64k page */
porder = 16;
} else
#endif
if ((ptel & 0xff000) == 0) {
/* 16M page */
porder = 24;
/* lowest AVA bit must be 0 for 16M pages */
if (pteh & 0x80) {
return H_PARAMETER;
}
} else {
return H_PARAMETER;
}
}
pa = ptel & HPTE_R_RPN;
/* FIXME: bounds check the pa? */
/* Check WIMG */
if ((ptel & HPTE_R_WIMG) != HPTE_R_M) {
return H_PARAMETER;
}
pteh &= ~0x60ULL;
if ((pte_index * HASH_PTE_SIZE_64) & ~env->htab_mask) {
return H_PARAMETER;
}
if (likely((flags & H_EXACT) == 0)) {
pte_index &= ~7ULL;
hpte = env->external_htab + (pte_index * HASH_PTE_SIZE_64);
for (i = 0; ; ++i) {
if (i == 8) {
return H_PTEG_FULL;
}
if (((ldq_p(hpte) & HPTE_V_VALID) == 0) &&
lock_hpte(hpte, HPTE_V_HVLOCK | HPTE_V_VALID)) {
break;
}
hpte += HASH_PTE_SIZE_64;
}
} else {
i = 0;
hpte = env->external_htab + (pte_index * HASH_PTE_SIZE_64);
if (!lock_hpte(hpte, HPTE_V_HVLOCK | HPTE_V_VALID)) {
return H_PTEG_FULL;
}
}
stq_p(hpte + (HASH_PTE_SIZE_64/2), ptel);
/* eieio(); FIXME: need some sort of barrier for smp? */
stq_p(hpte, pteh);
assert(!(ldq_p(hpte) & HPTE_V_HVLOCK));
args[0] = pte_index + i;
return H_SUCCESS;
}
static target_ulong h_remove(CPUState *env, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong flags = args[0];
target_ulong pte_index = args[1];
target_ulong avpn = args[2];
uint8_t *hpte;
target_ulong v, r, rb;
if ((pte_index * HASH_PTE_SIZE_64) & ~env->htab_mask) {
return H_PARAMETER;
}
hpte = env->external_htab + (pte_index * HASH_PTE_SIZE_64);
while (!lock_hpte(hpte, HPTE_V_HVLOCK)) {
/* We have no real concurrency in qemu soft-emulation, so we
* will never actually have a contested lock */
assert(0);
}
v = ldq_p(hpte);
r = ldq_p(hpte + (HASH_PTE_SIZE_64/2));
if ((v & HPTE_V_VALID) == 0 ||
((flags & H_AVPN) && (v & ~0x7fULL) != avpn) ||
((flags & H_ANDCOND) && (v & avpn) != 0)) {
stq_p(hpte, v & ~HPTE_V_HVLOCK);
assert(!(ldq_p(hpte) & HPTE_V_HVLOCK));
return H_NOT_FOUND;
}
args[0] = v & ~HPTE_V_HVLOCK;
args[1] = r;
stq_p(hpte, 0);
rb = compute_tlbie_rb(v, r, pte_index);
ppc_tlb_invalidate_one(env, rb);
assert(!(ldq_p(hpte) & HPTE_V_HVLOCK));
return H_SUCCESS;
}
static target_ulong h_protect(CPUState *env, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong flags = args[0];
target_ulong pte_index = args[1];
target_ulong avpn = args[2];
uint8_t *hpte;
target_ulong v, r, rb;
if ((pte_index * HASH_PTE_SIZE_64) & ~env->htab_mask) {
return H_PARAMETER;
}
hpte = env->external_htab + (pte_index * HASH_PTE_SIZE_64);
while (!lock_hpte(hpte, HPTE_V_HVLOCK)) {
/* We have no real concurrency in qemu soft-emulation, so we
* will never actually have a contested lock */
assert(0);
}
v = ldq_p(hpte);
r = ldq_p(hpte + (HASH_PTE_SIZE_64/2));
if ((v & HPTE_V_VALID) == 0 ||
((flags & H_AVPN) && (v & ~0x7fULL) != avpn)) {
stq_p(hpte, v & ~HPTE_V_HVLOCK);
assert(!(ldq_p(hpte) & HPTE_V_HVLOCK));
return H_NOT_FOUND;
}
r &= ~(HPTE_R_PP0 | HPTE_R_PP | HPTE_R_N |
HPTE_R_KEY_HI | HPTE_R_KEY_LO);
r |= (flags << 55) & HPTE_R_PP0;
r |= (flags << 48) & HPTE_R_KEY_HI;
r |= flags & (HPTE_R_PP | HPTE_R_N | HPTE_R_KEY_LO);
rb = compute_tlbie_rb(v, r, pte_index);
stq_p(hpte, v & ~HPTE_V_VALID);
ppc_tlb_invalidate_one(env, rb);
stq_p(hpte + (HASH_PTE_SIZE_64/2), r);
/* Don't need a memory barrier, due to qemu's global lock */
stq_p(hpte, v & ~HPTE_V_HVLOCK);
assert(!(ldq_p(hpte) & HPTE_V_HVLOCK));
return H_SUCCESS;
}
static target_ulong h_set_dabr(CPUState *env, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
/* FIXME: actually implement this */
return H_HARDWARE;
}
#define FLAGS_REGISTER_VPA 0x0000200000000000ULL
#define FLAGS_REGISTER_DTL 0x0000400000000000ULL
#define FLAGS_REGISTER_SLBSHADOW 0x0000600000000000ULL
#define FLAGS_DEREGISTER_VPA 0x0000a00000000000ULL
#define FLAGS_DEREGISTER_DTL 0x0000c00000000000ULL
#define FLAGS_DEREGISTER_SLBSHADOW 0x0000e00000000000ULL
#define VPA_MIN_SIZE 640
#define VPA_SIZE_OFFSET 0x4
#define VPA_SHARED_PROC_OFFSET 0x9
#define VPA_SHARED_PROC_VAL 0x2
static target_ulong register_vpa(CPUState *env, target_ulong vpa)
{
uint16_t size;
uint8_t tmp;
if (vpa == 0) {
hcall_dprintf("Can't cope with registering a VPA at logical 0\n");
return H_HARDWARE;
}
if (vpa % env->dcache_line_size) {
return H_PARAMETER;
}
/* FIXME: bounds check the address */
size = lduw_phys(vpa + 0x4);
if (size < VPA_MIN_SIZE) {
return H_PARAMETER;
}
/* VPA is not allowed to cross a page boundary */
if ((vpa / 4096) != ((vpa + size - 1) / 4096)) {
return H_PARAMETER;
}
env->vpa = vpa;
tmp = ldub_phys(env->vpa + VPA_SHARED_PROC_OFFSET);
tmp |= VPA_SHARED_PROC_VAL;
stb_phys(env->vpa + VPA_SHARED_PROC_OFFSET, tmp);
return H_SUCCESS;
}
static target_ulong deregister_vpa(CPUState *env, target_ulong vpa)
{
if (env->slb_shadow) {
return H_RESOURCE;
}
if (env->dispatch_trace_log) {
return H_RESOURCE;
}
env->vpa = 0;
return H_SUCCESS;
}
static target_ulong register_slb_shadow(CPUState *env, target_ulong addr)
{
uint32_t size;
if (addr == 0) {
hcall_dprintf("Can't cope with SLB shadow at logical 0\n");
return H_HARDWARE;
}
size = ldl_phys(addr + 0x4);
if (size < 0x8) {
return H_PARAMETER;
}
if ((addr / 4096) != ((addr + size - 1) / 4096)) {
return H_PARAMETER;
}
if (!env->vpa) {
return H_RESOURCE;
}
env->slb_shadow = addr;
return H_SUCCESS;
}
static target_ulong deregister_slb_shadow(CPUState *env, target_ulong addr)
{
env->slb_shadow = 0;
return H_SUCCESS;
}
static target_ulong register_dtl(CPUState *env, target_ulong addr)
{
uint32_t size;
if (addr == 0) {
hcall_dprintf("Can't cope with DTL at logical 0\n");
return H_HARDWARE;
}
size = ldl_phys(addr + 0x4);
if (size < 48) {
return H_PARAMETER;
}
if (!env->vpa) {
return H_RESOURCE;
}
env->dispatch_trace_log = addr;
env->dtl_size = size;
return H_SUCCESS;
}
static target_ulong deregister_dtl(CPUState *emv, target_ulong addr)
{
env->dispatch_trace_log = 0;
env->dtl_size = 0;
return H_SUCCESS;
}
static target_ulong h_register_vpa(CPUState *env, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong flags = args[0];
target_ulong procno = args[1];
target_ulong vpa = args[2];
target_ulong ret = H_PARAMETER;
CPUState *tenv;
for (tenv = first_cpu; tenv; tenv = tenv->next_cpu) {
if (tenv->cpu_index == procno) {
break;
}
}
if (!tenv) {
return H_PARAMETER;
}
switch (flags) {
case FLAGS_REGISTER_VPA:
ret = register_vpa(tenv, vpa);
break;
case FLAGS_DEREGISTER_VPA:
ret = deregister_vpa(tenv, vpa);
break;
case FLAGS_REGISTER_SLBSHADOW:
ret = register_slb_shadow(tenv, vpa);
break;
case FLAGS_DEREGISTER_SLBSHADOW:
ret = deregister_slb_shadow(tenv, vpa);
break;
case FLAGS_REGISTER_DTL:
ret = register_dtl(tenv, vpa);
break;
case FLAGS_DEREGISTER_DTL:
ret = deregister_dtl(tenv, vpa);
break;
}
return ret;
}
static target_ulong h_cede(CPUState *env, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
env->msr |= (1ULL << MSR_EE);
hreg_compute_hflags(env);
if (!cpu_has_work(env)) {
env->halted = 1;
}
return H_SUCCESS;
}
static target_ulong h_rtas(CPUState *env, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong rtas_r3 = args[0];
uint32_t token = ldl_phys(rtas_r3);
uint32_t nargs = ldl_phys(rtas_r3 + 4);
uint32_t nret = ldl_phys(rtas_r3 + 8);
return spapr_rtas_call(spapr, token, nargs, rtas_r3 + 12,
nret, rtas_r3 + 12 + 4*nargs);
}
spapr_hcall_fn papr_hypercall_table[(MAX_HCALL_OPCODE / 4) + 1];
spapr_hcall_fn kvmppc_hypercall_table[KVMPPC_HCALL_MAX - KVMPPC_HCALL_BASE];
void spapr_register_hypercall(target_ulong opcode, spapr_hcall_fn fn)
{
spapr_hcall_fn *slot;
if (opcode <= MAX_HCALL_OPCODE) {
assert((opcode & 0x3) == 0);
slot = &papr_hypercall_table[opcode / 4];
} else {
assert((opcode >= KVMPPC_HCALL_BASE) && (opcode <= KVMPPC_HCALL_MAX));
slot = &kvmppc_hypercall_table[opcode - KVMPPC_HCALL_BASE];
}
assert(!(*slot) || (fn == *slot));
*slot = fn;
}
target_ulong spapr_hypercall(CPUState *env, target_ulong opcode,
target_ulong *args)
{
if (msr_pr) {
hcall_dprintf("Hypercall made with MSR[PR]=1\n");
return H_PRIVILEGE;
}
if ((opcode <= MAX_HCALL_OPCODE)
&& ((opcode & 0x3) == 0)) {
spapr_hcall_fn fn = papr_hypercall_table[opcode / 4];
if (fn) {
return fn(env, spapr, opcode, args);
}
} else if ((opcode >= KVMPPC_HCALL_BASE) &&
(opcode <= KVMPPC_HCALL_MAX)) {
spapr_hcall_fn fn = kvmppc_hypercall_table[opcode - KVMPPC_HCALL_BASE];
if (fn) {
return fn(env, spapr, opcode, args);
}
}
hcall_dprintf("Unimplemented hcall 0x" TARGET_FMT_lx "\n", opcode);
return H_FUNCTION;
}
static void hypercall_init(void)
{
/* hcall-pft */
spapr_register_hypercall(H_ENTER, h_enter);
spapr_register_hypercall(H_REMOVE, h_remove);
spapr_register_hypercall(H_PROTECT, h_protect);
/* hcall-dabr */
spapr_register_hypercall(H_SET_DABR, h_set_dabr);
/* hcall-splpar */
spapr_register_hypercall(H_REGISTER_VPA, h_register_vpa);
spapr_register_hypercall(H_CEDE, h_cede);
/* qemu/KVM-PPC specific hcalls */
spapr_register_hypercall(KVMPPC_H_RTAS, h_rtas);
}
device_init(hypercall_init);