target/ppc: Add support for Radix partition-scoped translation

The Radix tree translation model currently supports process-scoped
translation for the PowerNV machine (Hypervisor mode) and for the
pSeries machine (Guest mode). Guests running under an emulated
Hypervisor (PowerNV machine) require a new type of Radix translation,
called partition-scoped, which is missing today.

The Radix tree translation is a 2 steps process. The first step,
process-scoped translation, converts an effective Address to a guest
real address, and the second step, partition-scoped translation,
converts a guest real address to a host real address.

There are difference cases to covers :

* Hypervisor real mode access: no Radix translation.

* Hypervisor or host application access (quadrant 0 and 3) with
  relocation on: process-scoped translation.

* Guest OS real mode access: only partition-scoped translation.

* Guest OS real or guest application access (quadrant 0 and 3) with
  relocation on: both process-scoped translation and partition-scoped
  translations.

* Hypervisor access in quadrant 1 and 2 with relocation on: both
  process-scoped translation and partition-scoped translations.

The radix tree partition-scoped translation is performed using tables
pointed to by the first double-word of the Partition Table Entries and
process-scoped translation uses tables pointed to by the Process Table
Entries (second double-word of the Partition Table Entries).

Both partition-scoped and process-scoped translations process are
identical and thus the radix tree traversing code is largely reused.
However, errors in partition-scoped translations generate hypervisor
exceptions.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20200403140056.59465-5-clg@kaod.org>
[dwg: Fixup from Greg Kurz folded in]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Cédric Le Goater 2020-04-03 16:00:56 +02:00 committed by David Gibson
parent 6bffd48b9e
commit d04ea940c5
3 changed files with 180 additions and 18 deletions

View file

@ -463,6 +463,9 @@ typedef struct ppc_v3_pate_t {
#define DSISR_AMR 0x00200000
/* Unsupported Radix Tree Configuration */
#define DSISR_R_BADCONFIG 0x00080000
#define DSISR_ATOMIC_RC 0x00040000
/* Unable to translate address of (guest) pde or process/page table entry */
#define DSISR_PRTABLE_FAULT 0x00020000
/* SRR1 error code fields */

View file

@ -506,9 +506,10 @@ static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp)
case POWERPC_EXCP_ISEG: /* Instruction segment exception */
case POWERPC_EXCP_TRACE: /* Trace exception */
break;
case POWERPC_EXCP_HISI: /* Hypervisor instruction storage exception */
msr |= env->error_code;
case POWERPC_EXCP_HDECR: /* Hypervisor decrementer exception */
case POWERPC_EXCP_HDSI: /* Hypervisor data storage exception */
case POWERPC_EXCP_HISI: /* Hypervisor instruction storage exception */
case POWERPC_EXCP_HDSEG: /* Hypervisor data segment exception */
case POWERPC_EXCP_HISEG: /* Hypervisor instruction segment exception */
case POWERPC_EXCP_SDOOR_HV: /* Hypervisor Doorbell interrupt */

View file

@ -103,6 +103,27 @@ static void ppc_radix64_raise_si(PowerPCCPU *cpu, int rwx, vaddr eaddr,
}
}
static void ppc_radix64_raise_hsi(PowerPCCPU *cpu, int rwx, vaddr eaddr,
hwaddr g_raddr, uint32_t cause)
{
CPUState *cs = CPU(cpu);
CPUPPCState *env = &cpu->env;
if (rwx == 2) { /* H Instruction Storage Interrupt */
cs->exception_index = POWERPC_EXCP_HISI;
env->spr[SPR_ASDR] = g_raddr;
env->error_code = cause;
} else { /* H Data Storage Interrupt */
cs->exception_index = POWERPC_EXCP_HDSI;
if (rwx == 1) { /* Write -> Store */
cause |= DSISR_ISSTORE;
}
env->spr[SPR_HDSISR] = cause;
env->spr[SPR_HDAR] = eaddr;
env->spr[SPR_ASDR] = g_raddr;
env->error_code = 0;
}
}
static bool ppc_radix64_check_prot(PowerPCCPU *cpu, int rwx, uint64_t pte,
int *fault_cause, int *prot,
@ -243,6 +264,37 @@ static bool validate_pate(PowerPCCPU *cpu, uint64_t lpid, ppc_v3_pate_t *pate)
return true;
}
static int ppc_radix64_partition_scoped_xlate(PowerPCCPU *cpu, int rwx,
vaddr eaddr, hwaddr g_raddr,
ppc_v3_pate_t pate,
hwaddr *h_raddr, int *h_prot,
int *h_page_size, bool pde_addr,
bool cause_excp)
{
int fault_cause = 0;
hwaddr pte_addr;
uint64_t pte;
*h_page_size = PRTBE_R_GET_RTS(pate.dw0);
/* No valid pte or access denied due to protection */
if (ppc_radix64_walk_tree(CPU(cpu)->as, g_raddr, pate.dw0 & PRTBE_R_RPDB,
pate.dw0 & PRTBE_R_RPDS, h_raddr, h_page_size,
&pte, &fault_cause, &pte_addr) ||
ppc_radix64_check_prot(cpu, rwx, pte, &fault_cause, h_prot, true)) {
if (pde_addr) /* address being translated was that of a guest pde */
fault_cause |= DSISR_PRTABLE_FAULT;
if (cause_excp) {
ppc_radix64_raise_hsi(cpu, rwx, eaddr, g_raddr, fault_cause);
}
return 1;
}
/* Update Reference and Change Bits */
ppc_radix64_set_rc(cpu, rwx, pte, pte_addr, h_prot);
return 0;
}
static int ppc_radix64_process_scoped_xlate(PowerPCCPU *cpu, int rwx,
vaddr eaddr, uint64_t pid,
ppc_v3_pate_t pate, hwaddr *g_raddr,
@ -250,9 +302,10 @@ static int ppc_radix64_process_scoped_xlate(PowerPCCPU *cpu, int rwx,
bool cause_excp)
{
CPUState *cs = CPU(cpu);
uint64_t offset, size, prtbe_addr, prtbe0, pte;
int fault_cause = 0;
hwaddr pte_addr;
CPUPPCState *env = &cpu->env;
uint64_t offset, size, prtbe_addr, prtbe0, base_addr, nls, index, pte;
int fault_cause = 0, h_page_size, h_prot;
hwaddr h_raddr, pte_addr;
int ret;
/* Index Process Table by PID to Find Corresponding Process Table Entry */
@ -266,18 +319,85 @@ static int ppc_radix64_process_scoped_xlate(PowerPCCPU *cpu, int rwx,
return 1;
}
prtbe_addr = (pate.dw1 & PATE1_R_PRTB) + offset;
prtbe0 = ldq_phys(cs->as, prtbe_addr);
if (cpu->vhyp) {
prtbe0 = ldq_phys(cs->as, prtbe_addr);
} else {
/*
* Process table addresses are subject to partition-scoped
* translation
*
* On a Radix host, the partition-scoped page table for LPID=0
* is only used to translate the effective addresses of the
* process table entries.
*/
ret = ppc_radix64_partition_scoped_xlate(cpu, 0, eaddr, prtbe_addr,
pate, &h_raddr, &h_prot,
&h_page_size, 1, 1);
if (ret) {
return ret;
}
prtbe0 = ldq_phys(cs->as, h_raddr);
}
/* Walk Radix Tree from Process Table Entry to Convert EA to RA */
*g_page_size = PRTBE_R_GET_RTS(prtbe0);
ret = ppc_radix64_walk_tree(cs->as, eaddr & R_EADDR_MASK,
prtbe0 & PRTBE_R_RPDB, prtbe0 & PRTBE_R_RPDS,
g_raddr, g_page_size, &pte, &fault_cause,
&pte_addr);
base_addr = prtbe0 & PRTBE_R_RPDB;
nls = prtbe0 & PRTBE_R_RPDS;
if (msr_hv || cpu->vhyp) {
/*
* Can treat process table addresses as real addresses
*/
ret = ppc_radix64_walk_tree(cs->as, eaddr & R_EADDR_MASK, base_addr,
nls, g_raddr, g_page_size, &pte,
&fault_cause, &pte_addr);
if (ret) {
/* No valid PTE */
if (cause_excp) {
ppc_radix64_raise_si(cpu, rwx, eaddr, fault_cause);
}
return ret;
}
} else {
uint64_t rpn, mask;
if (ret ||
ppc_radix64_check_prot(cpu, rwx, pte, &fault_cause, g_prot, false)) {
/* No valid pte or access denied due to protection */
index = (eaddr & R_EADDR_MASK) >> (*g_page_size - nls); /* Shift */
index &= ((1UL << nls) - 1); /* Mask */
pte_addr = base_addr + (index * sizeof(pte));
/*
* Each process table address is subject to a partition-scoped
* translation
*/
do {
ret = ppc_radix64_partition_scoped_xlate(cpu, 0, eaddr, pte_addr,
pate, &h_raddr, &h_prot,
&h_page_size, 1, 1);
if (ret) {
return ret;
}
ret = ppc_radix64_next_level(cs->as, eaddr & R_EADDR_MASK, &h_raddr,
&nls, g_page_size, &pte, &fault_cause);
if (ret) {
/* No valid pte */
if (cause_excp) {
ppc_radix64_raise_si(cpu, rwx, eaddr, fault_cause);
}
return ret;
}
pte_addr = h_raddr;
} while (!(pte & R_PTE_LEAF));
rpn = pte & R_PTE_RPN;
mask = (1UL << *g_page_size) - 1;
/* Or high bits of rpn and low bits to ea to form whole real addr */
*g_raddr = (rpn & ~mask) | (eaddr & mask);
}
if (ppc_radix64_check_prot(cpu, rwx, pte, &fault_cause, g_prot, false)) {
/* Access denied due to protection */
if (cause_excp) {
ppc_radix64_raise_si(cpu, rwx, eaddr, fault_cause);
}
@ -289,11 +409,29 @@ static int ppc_radix64_process_scoped_xlate(PowerPCCPU *cpu, int rwx,
return 0;
}
/*
* Radix tree translation is a 2 steps translation process:
*
* 1. Process-scoped translation: Guest Eff Addr -> Guest Real Addr
* 2. Partition-scoped translation: Guest Real Addr -> Host Real Addr
*
* MSR[HV]
* +-------------+----------------+---------------+
* | | HV = 0 | HV = 1 |
* +-------------+----------------+---------------+
* | Relocation | Partition | No |
* | = Off | Scoped | Translation |
* Relocation +-------------+----------------+---------------+
* | Relocation | Partition & | Process |
* | = On | Process Scoped | Scoped |
* +-------------+----------------+---------------+
*/
static int ppc_radix64_xlate(PowerPCCPU *cpu, vaddr eaddr, int rwx,
bool relocation,
hwaddr *raddr, int *psizep, int *protp,
bool cause_excp)
{
CPUPPCState *env = &cpu->env;
uint64_t lpid = 0, pid = 0;
ppc_v3_pate_t pate;
int psize, prot;
@ -325,11 +463,6 @@ static int ppc_radix64_xlate(PowerPCCPU *cpu, vaddr eaddr, int rwx,
}
return 1;
}
/* We don't support guest mode yet */
if (lpid != 0) {
error_report("PowerNV guest support Unimplemented");
exit(1);
}
}
*psizep = INT_MAX;
@ -340,6 +473,8 @@ static int ppc_radix64_xlate(PowerPCCPU *cpu, vaddr eaddr, int rwx,
*
* - Translates an effective address to a host real address in
* quadrants 0 and 3 when HV=1.
*
* - Translates an effective address to a guest real address.
*/
if (relocation) {
int ret = ppc_radix64_process_scoped_xlate(cpu, rwx, eaddr, pid,
@ -354,7 +489,30 @@ static int ppc_radix64_xlate(PowerPCCPU *cpu, vaddr eaddr, int rwx,
g_raddr = eaddr & R_EADDR_MASK;
}
*raddr = g_raddr;
if (cpu->vhyp) {
*raddr = g_raddr;
} else {
/*
* Perform partition-scoped translation if !HV or HV access to
* quadrants 1 or 2. Translates a guest real address to a host
* real address.
*/
if (lpid || !msr_hv) {
int ret;
ret = ppc_radix64_partition_scoped_xlate(cpu, rwx, eaddr, g_raddr,
pate, raddr, &prot, &psize,
0, cause_excp);
if (ret) {
return ret;
}
*psizep = MIN(*psizep, psize);
*protp &= prot;
} else {
*raddr = g_raddr;
}
}
return 0;
}