genode/repos/dde_linux/src/include/lx_emul/impl/internal/mapped_io_mem_range.h

113 lines
2.9 KiB
C++

/*
* \brief Representation of a locally-mapped MMIO range
* \author Norman Feske
* \date 2015-09-09
*/
/*
* Copyright (C) 2015 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _LX_EMUL__IMPL__INTERNAL__MAPPED_IO_MEM_RANGE_H_
#define _LX_EMUL__IMPL__INTERNAL__MAPPED_IO_MEM_RANGE_H_
/* Genode includes */
#include <os/attached_dataspace.h>
#include <io_mem_session/io_mem_session.h>
/* Linux emulation environment includes */
#include <lx_emul/impl/internal/list.h>
namespace Lx {
class Mapped_io_mem_range;
void *ioremap(resource_size_t, unsigned long, Genode::Cache_attribute);
}
/**
* Representation of a locally-mapped MMIO range
*
* This class is supposed to be a private utility to support 'ioremap'.
*/
class Lx::Mapped_io_mem_range : public Lx::List<Mapped_io_mem_range>::Element
{
private:
Genode::Attached_dataspace _ds;
Genode::size_t const _size;
Genode::addr_t const _phys;
Genode::addr_t const _virt;
public:
Mapped_io_mem_range(Genode::addr_t phys, Genode::size_t size,
Genode::Io_mem_dataspace_capability ds_cap)
:
_ds(ds_cap),
_size(size),
_phys(phys),
_virt((Genode::addr_t)_ds.local_addr<void>() | (phys & 0xfffUL))
{ }
Genode::addr_t phys() const { return _phys; }
Genode::addr_t virt() const { return _virt; }
/**
* Return true if the mapped range contains the specified sub range
*/
bool contains(Genode::addr_t phys, Genode::size_t size) const
{
return (phys >= _phys) && (phys + size - 1 <= _phys + _size - 1);
}
};
void *Lx::ioremap(resource_size_t phys_addr, unsigned long size,
Genode::Cache_attribute cache_attribute)
{
using namespace Genode;
static Lx::List<Lx::Mapped_io_mem_range> ranges;
/* search for the requested region within the already mapped ranges */
for (Lx::Mapped_io_mem_range *r = ranges.first(); r; r = r->next()) {
if (r->contains(phys_addr, size)) {
void * const virt = (void *)(r->virt() + phys_addr - r->phys());
PLOG("ioremap: return sub range phys 0x%lx (size %lx) to virt 0x%lx",
(long)phys_addr, (long)size, (long)virt);
return virt;
}
}
Io_mem_dataspace_capability ds_cap =
Lx::pci_dev_registry()->io_mem(phys_addr, cache_attribute, size);
if (!ds_cap.valid()) {
PERR("Failed to request I/O memory: [%zx,%lx)", phys_addr,
phys_addr + size);
return nullptr;
}
Genode::size_t const ds_size = Genode::Dataspace_client(ds_cap).size();
Lx::Mapped_io_mem_range *io_mem =
new (env()->heap()) Lx::Mapped_io_mem_range(phys_addr, ds_size, ds_cap);
ranges.insert(io_mem);
PLOG("ioremap: mapped phys 0x%lx (size %lx) to virt 0x%lx",
(long)phys_addr, (long)size, (long)io_mem->virt());
addr_t const sub_page_offset = phys_addr & 0xfff;
return (void *)(io_mem->virt() + sub_page_offset);
}
#endif /* _LX_EMUL__IMPL__INTERNAL__MAPPED_IO_MEM_RANGE_H_ */