Implement and use set_memory_registers_enable_mmu

exosphere/src/coldboot_init.c

@@ -9,10 +9,10 @@ extern const uint8_t __main_start__[], __main_end__[], __main_lma__[];
 extern const uint8_t __pk2ldr_start__[], __pk2ldr_end__[], __pk2ldr_lma__[];
 extern const uint8_t __vectors_start__[], __vectors_end__[], __vectors_lma__[];
 
-extern void flush_dcache_all_tzram_pa(void);
-extern void invalidate_icache_all_tzram_pa(void);
-
-uintptr_t get_coldboot_crt0_stack_address(void);
+/* warmboot_init.c */
+void set_memory_registers_enable_mmu(void);
+void flush_dcache_all_tzram_pa(void);
+void invalidate_icache_all_tzram_pa(void);
 
 static void identity_map_all_mappings(uintptr_t *mmu_l1_tbl, uintptr_t *mmu_l3_tbl) {
     static const uintptr_t addrs[]      =   { TUPLE_FOLD_LEFT_0(EVAL(IDENTIY_MAPPING_ID_MAX), _MMAPID, COMMA) };
@@ -123,16 +123,15 @@ __attribute__((target("cmodel=large"), noinline)) static void copy_other_section
 void coldboot_init(void) {
     /* TODO: Set NX BOOTLOADER clock time field */
     copy_warmboot_crt0();
-    /* TODO: set some mmio regs, etc. */
-    /* TODO: initialize DMA controllers */
+    /* At this point, we can (and will) access functions located in .warm_crt0 */
+    /* TODO: initialize DMA controllers, etc. */
     configure_ttbls();
     copy_other_sections();
-
-    /* TODO: set the MMU regs & tlbi & enable MMU */
+    set_memory_registers_enable_mmu();
 
     flush_dcache_all_tzram_pa();
     invalidate_icache_all_tzram_pa();
-    /* At this point we can access the mapped segments */
+    /* At this point we can access all the mapped segments */
     /* TODO: zero-initialize the cpu context */
-    /* Nintendo clears the (emtpy) pk2ldr's BSS section, but we embed it 0-filled in the binary */
+    /* Nintendo clears the (emtpy) pk2ldr's BSS section here , but we embed it 0-filled in the binary */
 }

exosphere/src/coldboot_main.c

@@ -5,9 +5,9 @@
 #include "arm.h"
 
 extern uint8_t __pk2ldr_start__[], __pk2ldr_end__[];
-extern void __jump_to_lower_el(uint64_t arg, uintptr_t ep, unsigned int el);
 
-void coldboot_main(void);
+/* start.s */
+void __jump_to_lower_el(uint64_t arg, uintptr_t ep, unsigned int el);
 
 void coldboot_main(void) {
     uintptr_t *mmu_l3_table = (uintptr_t *)TZRAM_GET_SEGMENT_ADDRESS(TZRAM_SEGMENT_ID_L3_TRANSLATION_TABLE);

exosphere/src/memory_map.h

@@ -4,8 +4,8 @@
 #include "mmu.h"
 #include "preprocessor.h"
 
-#define ATTRIB_MEMTYPE_NORMAL MMU_PTE_BLOCK_MEMTYPE(0)
-#define ATTRIB_MEMTYPE_DEVICE MMU_PTE_BLOCK_MEMTYPE(1)
+#define ATTRIB_MEMTYPE_NORMAL MMU_PTE_BLOCK_MEMTYPE(MMU_MT_NORMAL)
+#define ATTRIB_MEMTYPE_DEVICE MMU_PTE_BLOCK_MEMTYPE(MMU_MT_DEVICE_NGNRE)
 
 /* Identity mappings (addr, size, additional attributes, is block range) */
 #define _MMAPID0    ( 0x40020000ull, 0x20000ull,                                   0ull, false ) /* iRAM-C+D (contains the secmon's coldboot crt0) */

exosphere/src/mmu.h

@@ -32,11 +32,10 @@
  * SPDX-License-Identifier: GPL-2.0+
  */
 
-#define MMU_MT_DEVICE_NGNRNE    0ull
+/* Memory attributes, see set_memory_registers_enable_mmu */
+#define MMU_MT_NORMAL           0ull
 #define MMU_MT_DEVICE_NGNRE     1ull
-#define MMU_MT_DEVICE_GRE       2ull
-#define MMU_MT_NORMAL_NC        3ull
-#define MMU_MT_NORMAL           4ull
+#define MMU_MT_DEVICE_NGNRNE    2ull /* not used, also the same as Attr4-7 */
 
 /*
  * Hardware page table definitions.
@@ -112,6 +111,7 @@
 #define TCR_TG0_4K          (0 << 14)
 #define TCR_TG0_64K         (1 << 14)
 #define TCR_TG0_16K         (2 << 14)
+#define TCR_PS(x)           ((x) << 16)
 #define TCR_EPD1_DISABLE    BIT(23)
 
 #define TCR_EL1_RSVD        BIT(31)

exosphere/src/warmboot_init.c

@@ -1,12 +1,10 @@
 #include "utils.h"
 #include "memory_map.h"
 
+/* start.s */
 void __set_memory_registers(uintptr_t ttbr0, uintptr_t vbar, uint64_t cpuectlr, uint32_t scr,
                             uint32_t tcr, uint32_t cptr, uint64_t mair, uint32_t sctlr);
 
-uintptr_t get_warmboot_crt0_stack_address(void);
-void set_memory_registers(void);
-
 void flush_dcache_all_tzram_pa(void) {
     /* TODO */
 }
@@ -19,6 +17,59 @@ uintptr_t get_warmboot_crt0_stack_address(void) {
     return TZRAM_GET_SEGMENT_PA(TZRAM_SEGMENT_ID_CORE012_STACK) + 0x800;
 }
 
+void set_memory_registers_enable_mmu(void) {
+    static const uintptr_t vbar  = TZRAM_GET_SEGMENT_PA(TZRAM_SEGEMENT_ID_SECMON_EVT) + 0x800;
+    static const uintptr_t ttbr0 = vbar - 64;
+
+    /*
+        - Disable table walk descriptor access prefetch.
+        - L2 instruction fetch prefetch distance = 3 (reset value)
+        - L2 load/store data prefetch distance = 8 (reset value)
+        - Enable the processor to receive instruction cache and TLB maintenance operations broadcast from other processors in the cluster
+    */
+    static const uint64_t cpuectlr = 0x1B00000040ull;
+
+    /*
+        - The next lower level is Aarch64
+        - Secure instruction fetch (when the PE is in Secure state, this bit disables instruction fetch from Non-secure memory)
+        - External Abort/SError taken to EL3
+        - FIQ taken to EL3
+        - NS (EL0 and EL1 are nonsecure)
+    */
+    static const uint32_t scr = 0x63D;
+
+    /*
+        - PA size: 36-bit (64 GB)
+        - Granule size: 4KB
+        - Shareability attribute for memory associated with translation table walks using TTBR0_EL3: Inner Shareable
+        - Outer cacheability attribute for memory associated with translation table walks using TTBR0_EL3: Normal memory, Outer Write-Back Read-Allocate Write-Allocate Cacheable
+        - Inner cacheability attribute for memory associated with translation table walks using TTBR0_EL3: Normal memory, Inner Write-Back Read-Allocate Write-Allocate Cacheable
+        - T0SZ = 31 (33-bit address space)
+    */
+    static const uint32_t tcr = TCR_EL3_RSVD | TCR_PS(1) | TCR_TG0_4K | TCR_SHARED_INNER | TCR_ORGN_WBWA | TCR_IRGN_WBWA | TCR_T0SZ(33);
+
+    /* Nothing trapped */
+    static const uint32_t cptr = 0;
+
+    /*
+        - Attribute 0: Normal memory, Inner and Outer Write-Back Read-Allocate Write-Allocate Non-transient
+        - Attribute 1: Device-nGnRE memory
+        - Other attributes: Device-nGnRnE memory
+    */
+    static const uint64_t mair = 0x4FFull;
+
+    /*
+        - Cacheability control, for EL3 instruction accesses DISABLED
+        (- SP Alignment check bit NOT SET)
+        - Cacheability control, for EL3 data accesses DISABLED (normal memory accesses from EL3 are cacheable)
+        (- Alignement check bit NOT SET)
+        - MMU enabled for EL3 stage 1 address translation
+    */
+    static const uint32_t sctlr = 0x30C51835ull;
+
+    __set_memory_registers(ttbr0, vbar, cpuectlr, scr, tcr, cptr, mair, sctlr);
+}
+
 void warmboot_init(void) {
     /* TODO: Implement. */
 }

exosphere/src/warmboot_main.c

@@ -2,9 +2,8 @@
 #include "mmu.h"
 #include "memory_map.h"
 
-extern void __jump_to_lower_el(uint64_t arg, uintptr_t ep, unsigned int el);
-
-void warmboot_main(void);
+/* start.s */
+void __jump_to_lower_el(uint64_t arg, uintptr_t ep, unsigned int el);
 
 void warmboot_main(void) {
     /* TODO */