genode/repos/base-hw/src/core/spec/riscv/cpu.h
Norman Feske eba9c15746 Follow practices suggested by "Effective C++"
The patch adjust the code of the base, base-<kernel>, and os repository.
To adapt existing components to fix violations of the best practices
suggested by "Effective C++" as reported by the -Weffc++ compiler
argument. The changes follow the patterns outlined below:

* A class with virtual functions can no longer publicly inherit base
  classed without a vtable. The inherited object may either be moved
  to a member variable, or inherited privately. The latter would be
  used for classes that inherit 'List::Element' or 'Avl_node'. In order
  to enable the 'List' and 'Avl_tree' to access the meta data, the
  'List' must become a friend.

* Instead of adding a virtual destructor to abstract base classes,
  we inherit the new 'Interface' class, which contains a virtual
  destructor. This way, single-line abstract base classes can stay
  as compact as they are now. The 'Interface' utility resides in
  base/include/util/interface.h.

* With the new warnings enabled, all member variables must be explicitly
  initialized. Basic types may be initialized with '='. All other types
  are initialized with braces '{ ... }' or as class initializers. If
  basic types and non-basic types appear in a row, it is nice to only
  use the brace syntax (also for basic types) and align the braces.

* If a class contains pointers as members, it must now also provide a
  copy constructor and assignment operator. In the most cases, one
  would make them private, effectively disallowing the objects to be
  copied. Unfortunately, this warning cannot be fixed be inheriting
  our existing 'Noncopyable' class (the compiler fails to detect that
  the inheriting class cannot be copied and still gives the error).
  For now, we have to manually add declarations for both the copy
  constructor and assignment operator as private class members. Those
  declarations should be prepended with a comment like this:

        /*
         * Noncopyable
         */
        Thread(Thread const &);
        Thread &operator = (Thread const &);

  In the future, we should revisit these places and try to replace
  the pointers with references. In the presence of at least one
  reference member, the compiler would no longer implicitly generate
  a copy constructor. So we could remove the manual declaration.

Issue #465
2018-01-17 12:14:35 +01:00

88 lines
1.8 KiB
C++

/*
* \brief CPU driver for core
* \author Sebastian Sumpf
* \date 2015-06-02
*/
/*
* Copyright (C) 2015-2017 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__RISCV__CPU_H_
#define _CORE__SPEC__RISCV__CPU_H_
/* Genode includes */
#include <base/stdint.h>
#include <cpu/cpu_state.h>
#include <util/register.h>
#include <base/internal/align_at.h>
#include <kernel/interface.h>
#include <hw/spec/riscv/cpu.h>
namespace Kernel { struct Thread_fault; }
namespace Genode
{
/**
* CPU driver for core
*/
class Cpu;
typedef __uint128_t sizet_arithm_t;
}
namespace Kernel { class Pd; }
class Genode::Cpu : public Hw::Riscv_cpu
{
public:
struct alignas(8) Context : Cpu_state
{
Context(bool);
};
struct Mmu_context
{
Sptbr::access_t sptbr = 0;
Mmu_context(addr_t page_table_base);
~Mmu_context();
};
/**
* From the manual
*
* The behavior of SFENCE.VM depends on the current value of the sasid
* register. If sasid is nonzero, SFENCE.VM takes effect only for address
* translations in the current address space. If sasid is zero, SFENCE.VM
* affects address translations for all address spaces. In this case, it
* also affects global mappings, which are described in Section 4.5.1.
*
* Right no we will flush anything
*/
static void sfence()
{
/*
* Note: In core the address space id must be zero
*/
asm volatile ("sfence.vm\n");
}
static void invalidate_tlb_by_pid(unsigned const /* pid */) { sfence(); }
void switch_to(Mmu_context & context);
static void mmu_fault(Context & c, Kernel::Thread_fault & f);
static unsigned executing_id() { return 0; }
static unsigned primary_id() { return 0; }
};
#endif /* _CORE__SPEC__RISCV__CPU_H_ */