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Kernel: Map DMA and PCI MMIO as uncached

This commit is contained in:
Bananymous 2024-07-30 11:10:08 +03:00
parent bb1738db8c
commit 9bc02c81f8
5 changed files with 11 additions and 9 deletions
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13
kernel/arch/i686/PageTable.cpp
View File

@ -369,13 +369,12 @@ namespace Kernel
if (flags & Flags::Reserved)
extra_flags |= Flags::Reserved;
if (s_has_pat)
{
if (memory_type == MemoryType::WriteCombining)
extra_flags |= (1ull << 7);
if (memory_type == MemoryType::WriteThrough)
extra_flags |= (1ull << 7) | (1ull << 3);
}
if (memory_type == MemoryType::Uncached)
extra_flags |= (1ull << 4);
if (s_has_pat && memory_type == MemoryType::WriteCombining)
extra_flags |= (1ull << 7);
if (s_has_pat && memory_type == MemoryType::WriteThrough)
extra_flags |= (1ull << 7) | (1ull << 3);
// NOTE: we add present here, since it has to be available in higher level structures
flags_t uwr_flags = (flags & (Flags::UserSupervisor | Flags::ReadWrite)) | Flags::Present;

2
kernel/arch/x86_64/PageTable.cpp
View File

@ -417,6 +417,8 @@ namespace Kernel
if (flags & Flags::Reserved)
extra_flags |= Flags::Reserved;
if (memory_type == MemoryType::Uncached)
extra_flags |= (1ull << 4);
if (memory_type == MemoryType::WriteCombining)
extra_flags |= (1ull << 7);
if (memory_type == MemoryType::WriteThrough)

1
kernel/include/kernel/Memory/PageTable.h
View File

@ -37,6 +37,7 @@ namespace Kernel
enum MemoryType
{
Normal,
Uncached,
WriteCombining,
WriteThrough,
};

2
kernel/kernel/Memory/DMARegion.cpp
View File

@ -26,7 +26,7 @@ namespace Kernel
vaddr_guard.disable();
paddr_guard.disable();
PageTable::kernel().map_range_at(paddr, vaddr, size, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
PageTable::kernel().map_range_at(paddr, vaddr, size, PageTable::Flags::ReadWrite | PageTable::Flags::Present, PageTable::MemoryType::Uncached);
return BAN::UniqPtr<DMARegion>::adopt(region_ptr);
}

2
kernel/kernel/PCI.cpp
View File

@ -246,7 +246,7 @@ namespace Kernel::PCI
{
vaddr_t vaddr = PageTable::kernel().reserve_free_page(KERNEL_OFFSET);
ASSERT(vaddr);
PageTable::kernel().map_page_at(pcie_paddr, vaddr, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
PageTable::kernel().map_page_at(pcie_paddr, vaddr, PageTable::Flags::ReadWrite | PageTable::Flags::Present, PageTable::MemoryType::Uncached);
m_mmio_config = vaddr;
}