exo2: implement warmboot through start of virtual exec

This commit is contained in:
Michael Scire 2020-05-12 21:51:26 -07:00 committed by SciresM
parent dc6abf9f68
commit 81846fa5c3
2 changed files with 180 additions and 2 deletions

View file

@ -26,8 +26,12 @@ namespace ams::secmon {
namespace {
constexpr inline uintptr_t MC = MemoryRegionPhysicalDeviceMemoryController.GetAddress();
using namespace ams::mmu;
constexpr inline PageTableMappingAttribute MappingAttributesEl3SecureRwCode = AddMappingAttributeIndex(PageTableMappingAttributes_El3SecureRwCode, MemoryAttributeIndexNormal);
void SetupCpuCommonControllers() {
/* Set cpuactlr_el1. */
{
@ -146,6 +150,69 @@ namespace ams::secmon {
hw::InstructionSynchronizationBarrier();
}
bool IsExitLp0() {
return reg::Read(MC + MC_SECURITY_CFG3) == 0;
}
constexpr void AddPhysicalTzramIdentityMappingImpl(u64 *l1, u64 *l2, u64 *l3) {
/* Define extents. */
const uintptr_t start_address = MemoryRegionPhysicalTzram.GetAddress();
const size_t size = MemoryRegionPhysicalTzram.GetSize();
const uintptr_t end_address = start_address + size;
/* Flush cache for the L3 page table entries. */
{
const uintptr_t start = GetL3EntryIndex(start_address);
const uintptr_t end = GetL3EntryIndex(end_address);
for (uintptr_t i = start; i < end; i += hw::DataCacheLineSize / sizeof(*l3)) {
if (!std::is_constant_evaluated()) { hw::FlushDataCacheLine(l3 + i); }
}
}
/* Flush cache for the L2 page table entry. */
if (!std::is_constant_evaluated()) { hw::FlushDataCacheLine(l2 + GetL2EntryIndex(start_address)); }
/* Flush cache for the L1 page table entry. */
if (!std::is_constant_evaluated()) { hw::FlushDataCacheLine(l1 + GetL1EntryIndex(start_address)); }
/* Add the L3 mappings. */
SetL3BlockEntry(l3, start_address, start_address, size, MappingAttributesEl3SecureRwCode);
/* Add the L2 entry for the physical tzram region. */
SetL2TableEntry(l2, MemoryRegionPhysicalTzramL2.GetAddress(), MemoryRegionPhysicalTzramL2L3PageTable.GetAddress(), PageTableTableAttributes_El3SecureCode);
/* Add the L1 entry for the physical region. */
SetL1TableEntry(l1, MemoryRegionPhysical.GetAddress(), MemoryRegionPhysicalTzramL2L3PageTable.GetAddress(), PageTableTableAttributes_El3SecureCode);
static_assert(GetL1EntryIndex(MemoryRegionPhysical.GetAddress()) == 1);
/* Invalidate the data cache for the L3 page table entries. */
{
const uintptr_t start = GetL3EntryIndex(start_address);
const uintptr_t end = GetL3EntryIndex(end_address);
for (uintptr_t i = start; i < end; i += hw::DataCacheLineSize / sizeof(*l3)) {
if (!std::is_constant_evaluated()) { hw::InvalidateDataCacheLine(l3 + i); }
}
}
/* Flush cache for the L2 page table entry. */
if (!std::is_constant_evaluated()) { hw::InvalidateDataCacheLine(l2 + GetL2EntryIndex(start_address)); }
/* Flush cache for the L1 page table entry. */
if (!std::is_constant_evaluated()) { hw::InvalidateDataCacheLine(l1 + GetL1EntryIndex(start_address)); }
}
void AddPhysicalTzramIdentityMapping() {
/* Get page table extents. */
u64 * const l1 = MemoryRegionPhysicalTzramL1PageTable.GetPointer<u64>();
u64 * const l2_l3 = MemoryRegionPhysicalTzramL2L3PageTable.GetPointer<u64>();
/* Add the mapping. */
AddPhysicalTzramIdentityMappingImpl(l1, l2_l3, l2_l3);
/* Ensure that mappings are consistent. */
setup::EnsureMappingConsistency();
}
}
void SetupCpuMemoryControllersEnableMmu() {
@ -204,7 +271,16 @@ namespace ams::secmon {
}
void SetupSocDmaControllersCpuMemoryControllersEnableMmuWarmboot() {
/* TODO */
/* If this is being called from lp0 exit, we want to setup the soc dma controllers. */
if (IsExitLp0()) {
SetupSocDmaControllers();
}
/* Add a physical TZRAM identity map. */
AddPhysicalTzramIdentityMapping();
/* Initialize cpu memory controllers and the MMU. */
SetupCpuMemoryControllersEnableMmu();
}
}

View file

@ -95,10 +95,11 @@ _start_warm:
ERRATUM_INVALIDATE_BTB_AT_BOOT
/* Acquire exclusive access to the common warmboot stack. */
bl _ZN3ams6secmon26AcquireCommonWarmbootStackEv
/* Set the stack pointer to the common warmboot stack address. */
msr spsel, #1
ldr x20, =0x1F01F67C0
ldr x20, =0x7C0107C0
mov sp, x20
/* Perform warmboot setup. */
@ -108,3 +109,104 @@ _start_warm:
b _ZN3ams6secmon20StartWarmbootVirtualEv
/* void ams::secmon::AcquireCommonWarmbootStack() { */
/* NOTE: This implements critical section enter via https://en.wikipedia.org/wiki/Lamport%27s_bakery_algorithm */
/* This algorithm is used because the MMU is not awake yet, so exclusive load/store instructions are not usable. */
/* NOTE: Nintendo attempted to implement this algorithm themselves, but did not really understand how it works. */
/* They use the same ticket number for all cores; this can lead to starvation and other problems. */
.section .warmboot.text._ZN3ams6secmon26AcquireCommonWarmbootStackEv, "ax", %progbits
.align 4
.global _ZN3ams6secmon26AcquireCommonWarmbootStackEv
_ZN3ams6secmon26AcquireCommonWarmbootStackEv:
/* BakeryLock *lock = std::addressof(secmon::CommonWarmBootStackLock); */
ldr x0, =_ZN3ams6secmon23CommonWarmbootStackLockE
/* const u32 id = GetCurrentCoreId(); */
mrs x8, mpidr_el1
and x8, x8, #3
/* lock->customers[id].is_entering = true; */
ldrb w2, [x0, x8]
orr w2, w2, #~0x7F
strb w2, [x0, x8]
/* const u8 ticket_0 = lock->customers[0].ticket_number; */
ldrb w4, [x0, #0]
and w4, w4, #0x7F
/* const u8 ticket_1 = lock->customers[1].ticket_number; */
ldrb w5, [x0, #1]
and w5, w5, #0x7F
/* const u8 ticket_2 = lock->customers[2].ticket_number; */
ldrb w6, [x0, #2]
and w6, w6, #0x7F
/* const u8 ticket_3 = lock->customers[3].ticket_number; */
ldrb w7, [x0, #3]
and w7, w7, #0x7F
/* u8 biggest_ticket = std::max(std::max(ticket_0, ticket_1), std::max(ticket_2, ticket_3)) */
cmp w4, w5
csel w2, w4, w5, hi
cmp w6, w7
csel w3, w6, w7, hi
cmp w2, w3
csel w2, w2, w3, hi
/* NOTE: The biggest a ticket can ever be is 4, so the general increment is safe and 7-bit increment is not needed. */
/* lock->customers[id] = { .is_entering = false, .ticket_number = ++biggest_ticket }; */
add w2, w2, #1
strb w2, [x0, x8]
/* Ensure instructions aren't reordered around this point. */
/* hw::DataSynchronizationBarrier(); */
dsb sy
/* hw::SendEvent(); */
sev
/* for (unsigned int i = 0; i < 4; ++i) { */
mov w3, #0
1:
/* hw::SendEventLocal(); */
sevl
/* do { */
2:
/* hw::WaitForEvent(); */
wfe
/* while (lock->customers[i].is_entering); */
ldrb w4, [x0, x3]
tbnz w4, #7, 2b
/* u8 their_ticket; */
/* hw::SendEventLocal(); */
sevl
/* do { */
2:
/* hw::WaitForEvent(); */
wfe
/* their_ticket = lock->customers[i].ticket_number; */
ldrb w4, [x0, x3]
ands w4, w4, #0x7F
/* if (their_ticket == 0) { break; } */
b.eq 3f
/* while ((their_ticket > my_ticket) || (their_ticket == my_ticket && id > i)); */
cmp w2, w4
b.hi 2b
ccmp w8, w3, #0, eq
b.hi 2b
/* } */
3:
add w3, w3, #1
cmp w3, #4
b.ne 1b
/* hw::DataMemoryBarrier(); */
dmb sy
ret