From c7b47accc6de3521f10c323983a1b325a60fb421 Mon Sep 17 00:00:00 2001
From: Wojtek Kosior <kwojtus@protonmail.com>
Date: Wed, 15 Jan 2020 15:22:16 +0100
Subject: also enable data and instruction cache when enabling the MMU

---
 src/arm/PL1/kernel/paging.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

(limited to 'src')

diff --git a/src/arm/PL1/kernel/paging.c b/src/arm/PL1/kernel/paging.c
index 771c681..4c3dccf 100644
--- a/src/arm/PL1/kernel/paging.c
+++ b/src/arm/PL1/kernel/paging.c
@@ -101,10 +101,11 @@ void setup_flat_map(void)
   // enable MMU
   puts("enabling the MMU");
 
-  // redundant - we already have SCTLR contents in the variable
-  // asm("mrc p15, 0, %0, c1, c0, 0" : "=r" (SCTLR.raw));
+  // we already have SCTLR contents in the variable
 
-  SCTLR.fields.M = 1;
+  SCTLR.fields.M = 1; // enable MMU
+  SCTLR.fields.C = 1; // enable data cache
+  SCTLR.fields.I = 1; // enable instruction cache
 
   asm("mcr p15, 0, %0, c1, c0, 0\n\r"
       "isb" :: "r" (SCTLR.raw) : "memory");
-- 
cgit v1.2.3


From c77286c6951223be1c216c19278cecca3b43ceb5 Mon Sep 17 00:00:00 2001
From: Wojtek Kosior <kwojtus@protonmail.com>
Date: Wed, 15 Jan 2020 16:30:05 +0100
Subject: for safety - invalidate caches when creating a new mapping

---
 src/arm/PL1/kernel/paging.c | 8 ++++++++
 1 file changed, 8 insertions(+)

(limited to 'src')

diff --git a/src/arm/PL1/kernel/paging.c b/src/arm/PL1/kernel/paging.c
index 4c3dccf..6da9905 100644
--- a/src/arm/PL1/kernel/paging.c
+++ b/src/arm/PL1/kernel/paging.c
@@ -242,6 +242,14 @@ uint16_t claim_and_map_section
   // write modified descriptor to the table
   *section_entry = descriptor;
   
+  // invalidate instruction cache
+  asm("mcr p15, 0, r0, c7, c5, 0\n\r" // r0 gets ignored
+      "isb" ::: "memory");
+
+  // invalidate branch-prediction
+  asm("mcr p15, 0, r0, c7, c5, 6\n\r" // r0 - same as above
+      "isb" ::: "memory");
+
   // invalidate main Translation Lookup Buffer
   asm("mcr p15, 0, r1, c8, c7, 0\n\r"
       "isb" ::: "memory");
-- 
cgit v1.2.3


From ca3bf744f826225bb041afc4779ee19493d5440e Mon Sep 17 00:00:00 2001
From: Wojtek Kosior <kwojtus@protonmail.com>
Date: Wed, 15 Jan 2020 16:47:14 +0100
Subject: remove garbage-comments

---
 src/arm/PL1/kernel/interrupts.c | 33 +--------------------------------
 1 file changed, 1 insertion(+), 32 deletions(-)

(limited to 'src')

diff --git a/src/arm/PL1/kernel/interrupts.c b/src/arm/PL1/kernel/interrupts.c
index 121d79c..5695e6f 100644
--- a/src/arm/PL1/kernel/interrupts.c
+++ b/src/arm/PL1/kernel/interrupts.c
@@ -3,11 +3,8 @@
 #include "svc_interface.h"
 #include "armclock.h"
 #include "scheduler.h"
-/**
-    @brief The undefined instruction interrupt handler
-**/
-
 
+// defined in setup.c
 void __attribute__((noreturn)) setup(void);
 
 // from what I've heard, reset is never used on the Pi;
@@ -105,31 +102,3 @@ void fiq_handler(void)
 {
   error("fiq happened");
 }
-
-
-/* Here is your interrupt function */
-//void
-//__attribute__((interrupt("IRQ")))
-//__attribute__((section(".interrupt_vectors.text")))
-//irq_handler2(void) {
-//    /* You code goes here */
-////    uart_puts("GOT INTERRUPT!\r\n");
-//
-//    local_timer_clr_reload_reg_t temp = { .IntClear = 1, .Reload = 1 };
-//    QA7->TimerClearReload  = temp;									// Clear interrupt & reload
-//}
-
-///* here is your main */
-//int enable_timer(void) {
-//
-//    QA7->TimerRouting.Routing = LOCALTIMER_TO_CORE0_IRQ;			// Route local timer IRQ to Core0
-//    QA7->TimerControlStatus.ReloadValue = 100;						// Timer period set
-//    QA7->TimerControlStatus.TimerEnable = 1;						// Timer enabled
-//    QA7->TimerControlStatus.IntEnable = 1;							// Timer IRQ enabled
-//    QA7->TimerClearReload.IntClear = 1;								// Clear interrupt
-//    QA7->TimerClearReload.Reload = 1;								// Reload now
-//    QA7->Core0TimerIntControl.nCNTPNSIRQ_IRQ = 1;					// We are in NS EL1 so enable IRQ to core0 that level
-//    QA7->Core0TimerIntControl.nCNTPNSIRQ_FIQ = 0;					// Make sure FIQ is zero
-////    uart_puts("Enabled Timer\r\n");
-//    return(0);
-//}
\ No newline at end of file
-- 
cgit v1.2.3