genode/repos/base-hw/src/core/spec/cortex_a15/cpu.h
Alexander Boettcher de06eefbac hw: evaluate write fault on RO page
rm_fault.run triggers write on read-only ROM provided by core, which
fails without this patch:

arm - "raised unhandled data abort"
x86 - (silent/invisible) busy loop because write fault gets never resolved
2017-08-17 11:04:22 +02:00

276 lines
6.7 KiB
C++

/*
* \brief CPU driver for core
* \author Martin stein
* \author Stefan Kalkowski
* \date 2011-11-03
*/
/*
* Copyright (C) 2011-2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
#ifndef _CORE__SPEC__CORTEX_A15__CPU_H_
#define _CORE__SPEC__CORTEX_A15__CPU_H_
/* core includes */
#include <spec/arm_v7/cpu_support.h>
namespace Genode { class Cpu; }
class Genode::Cpu : public Arm_v7_cpu
{
public:
/**
* Translation table base register 0 (64-bit format)
*/
struct Ttbr0 : Ttbr0_64bit
{
enum Memory_region { NON_CACHEABLE = 0, CACHEABLE = 1 };
/**
* Return initialized value
*
* \param table base of targeted translation table
*/
static access_t init(addr_t const table, unsigned const id)
{
access_t v = Ttbr_64bit::Ba::masked((access_t)table);
Ttbr_64bit::Asid::set(v, id);
return v;
}
static Genode::uint32_t init(addr_t const table) {
return table; }
};
/*********************************
** Virtualization extensions **
*********************************/
/**
* Hypervisor system trap register
*/
struct Hstr : Register<32>
{
/* System coprocessor primary register access trap */
template <unsigned R>
struct T : Bitfield<R, 1> {};
static access_t init()
{
/*
* allow cache (7), TLB (8) maintenance, and performance
* monitor (9), process/thread ID register (13) and timer (14)
* access.
*/
access_t v = 0;
T<0>::set(v, 1);
T<1>::set(v, 1);
T<2>::set(v, 1);
T<3>::set(v, 1);
T<5>::set(v, 1);
T<6>::set(v, 1);
T<10>::set(v, 1);
T<11>::set(v, 1);
T<12>::set(v, 1);
T<15>::set(v, 1);
return v;
};
};
/**
* Hypervisor control register
*/
struct Hcr : Register<32>
{
struct Vm : Bitfield<0, 1> {}; /* VT MMU enabled */
struct Fmo : Bitfield<3, 1> {}; /* FIQ cannot been masked */
struct Imo : Bitfield<4, 1> {}; /* IRQ cannot been masked */
struct Amo : Bitfield<5, 1> {}; /* A bit cannot been masked */
struct Twi : Bitfield<13, 1> {}; /* trap on WFI instruction */
struct Twe : Bitfield<14, 1> {}; /* trap on WFE instruction */
struct Tidcp : Bitfield<20, 1> {}; /* trap lockdown */
struct Tac : Bitfield<21, 1> {}; /* trap ACTLR accesses */
struct Tvm : Bitfield<26, 1> {}; /* trap virtual memory ctrls */
static access_t init()
{
access_t v = 0;
Vm::set(v, 1);
Fmo::set(v, 1);
Imo::set(v, 1);
Amo::set(v, 1);
Twi::set(v, 1);
Twe::set(v, 1);
Tidcp::set(v, 1);
Tac::set(v, 1);
Tvm::set(v, 1);
return v;
};
};
/**
* Extend basic CPU state by members relevant for 'base-hw' only
*
* Note: this class redefines Genode::Arm::Context
*/
struct Context : Genode::Cpu_state
{
Ttbr0::access_t ttbr0 = 0;
addr_t sctlr = 0;
addr_t ttbrc = 0;
addr_t mair0 = 0;
/**
* Return base of assigned translation table
*/
addr_t translation_table() const {
return Ttbr_64bit::Ba::masked(ttbr0); }
/**
* Assign translation-table base 'table'
*/
void translation_table(addr_t const table) {
Ttbr_64bit::Ba::set(ttbr0, (Ttbr_64bit::access_t)(table >> 5)); }
/**
* Assign protection domain
*/
void protection_domain(Genode::uint8_t const id) {
Ttbr_64bit::Asid::set(ttbr0, id); }
};
/**
* An usermode execution state
*
* FIXME: this class largely overlaps with Genode::Arm::User_context
*/
struct User_context : Context
{
User_context()
{
Psr::access_t v = 0;
Psr::M::set(v, Psr::M::USR);
Psr::F::set(v, 1);
Psr::A::set(v, 1);
cpsr = v;
}
/**
* Support for kernel calls
*/
void user_arg_0(unsigned const arg) { r0 = arg; }
void user_arg_1(unsigned const arg) { r1 = arg; }
void user_arg_2(unsigned const arg) { r2 = arg; }
void user_arg_3(unsigned const arg) { r3 = arg; }
void user_arg_4(unsigned const arg) { r4 = arg; }
void user_arg_5(unsigned const arg) { r5 = arg; }
void user_arg_6(unsigned const arg) { r6 = arg; }
void user_arg_7(unsigned const arg) { r7 = arg; }
unsigned user_arg_0() const { return r0; }
unsigned user_arg_1() const { return r1; }
unsigned user_arg_2() const { return r2; }
unsigned user_arg_3() const { return r3; }
unsigned user_arg_4() const { return r4; }
unsigned user_arg_5() const { return r5; }
unsigned user_arg_6() const { return r6; }
unsigned user_arg_7() const { return r7; }
/**
* Initialize thread context
*
* \param table physical base of appropriate translation table
* \param pd_id kernel name of appropriate protection domain
*/
void init_thread(addr_t const table, unsigned const pd_id)
{
protection_domain(pd_id);
translation_table(table);
}
/**
* Return if the context is in a page fault due to translation miss
*
* \param va holds the virtual fault-address if call returns 1
* \param w holds wether it's a write fault if call returns 1
*/
bool in_fault(addr_t & va, addr_t & w) const
{
/* permission fault on page, 2nd level */
static constexpr Fsr::access_t permission = 0b1111;
switch (cpu_exception) {
case PREFETCH_ABORT:
{
/* check if fault was caused by a translation miss */
Fsr::access_t const fs = Fsr::Fs::get(Ifsr::read());
if ((fs & 0b11100) != 0b100) return false;
/* fetch fault data */
w = 0;
va = ip;
return true;
}
case DATA_ABORT:
{
/* check if fault was caused by translation miss */
Fsr::access_t const fs = Fsr::Fs::get(Dfsr::read());
if ((fs != permission) && (fs & 0b11100) != 0b100)
return false;
/* fetch fault data */
Dfsr::access_t const dfsr = Dfsr::read();
w = Dfsr::Wnr::get(dfsr);
va = Dfar::read();
return true;
}
default:
return false;
};
}
};
/**
* Return kernel name of the executing CPU
*/
static unsigned executing_id() { return Mpidr::Aff_0::get(Mpidr::read()); }
/**
* Return kernel name of the primary CPU
*/
static unsigned primary_id();
/**
* Write back dirty cache lines and invalidate all cache lines
*/
void clean_invalidate_data_cache() {
clean_invalidate_inner_data_cache(); }
/**
* Invalidate all cache lines
*/
void invalidate_data_cache() {
invalidate_inner_data_cache(); }
/*************
** Dummies **
*************/
void switch_to(User_context&) { }
bool retry_undefined_instr(Context&) { return false; }
};
#endif /* _CORE__SPEC__CORTEX_A15__CPU_H_ */