Created student weenix repository

1 files changed, 138 insertions, 0 deletions

diff --git a/kernel/main/smp.c b/kernel/main/smp.c
new file mode 100644
index 0000000..fb85469
--- /dev/null
+++ b/kernel/main/smp.c
@@ -0,0 +1,138 @@
+#include "globals.h"
+#include "types.h"
+#include <main/gdt.h>
+
+#include "main/apic.h"
+#include "main/inits.h"
+
+#include "mm/tlb.h"
+
+#include "util/string.h"
+#include "util/time.h"
+
+static long smp_processor_count;
+
+extern uintptr_t smp_initialization_start;
+extern uintptr_t smp_initialization_end;
+#define smp_initialization_start ((uintptr_t)(&smp_initialization_start))
+#define smp_initialization_end ((uintptr_t)(&smp_initialization_end))
+#define smp_initialization_size \
+    (smp_initialization_end - smp_initialization_start)
+
+static void smp_start_processor(uint8_t apic_id);
+static long smp_stop_processor(regs_t *regs);
+
+extern void *csd_start;
+extern void *csd_end;
+#define CSD_START ((uintptr_t)&csd_start)
+#define CSD_END ((uintptr_t)&csd_end)
+#define CSD_PAGES (uintptr_t)((CSD_END - CSD_START) >> PAGE_SHIFT)
+
+core_t curcore CORE_SPECIFIC_DATA;
+uintptr_t csd_vaddr_table[MAX_LAPICS] = {NULL};
+
+void map_in_core_specific_data(pml4_t *pml4)
+{
+    pt_map_range(pml4, curcore.kc_csdpaddr, CSD_START, CSD_END,
+                 PT_PRESENT | PT_WRITE, PT_PRESENT | PT_WRITE);
+    uintptr_t mapped_paddr = pt_virt_to_phys_helper(pml4, (uintptr_t)&curcore);
+    uintptr_t expected_paddr =
+        (uintptr_t)GET_CSD(curcore.kc_id, core_t, curcore) - PHYS_OFFSET;
+    uintptr_t expected_paddr2 =
+        pt_virt_to_phys_helper(pt_get(), (uintptr_t)&curcore);
+    KASSERT(mapped_paddr == expected_paddr);
+    KASSERT(expected_paddr == expected_paddr2);
+}
+
+long is_core_specific_data(void *addr)
+{
+    return (uintptr_t)addr >= CSD_START && (uintptr_t)addr < CSD_END;
+}
+
+void core_init()
+{
+    // order of operations are pretty important here
+    pt_init();
+    pt_set(pt_create());
+
+    uintptr_t csd_paddr = (uintptr_t)page_alloc_n(CSD_PAGES);
+    if (!csd_paddr)
+        panic("not enough memory for core-specific data!");
+    csd_vaddr_table[apic_current_id()] =
+        csd_paddr; // still in PHYSMAP region; still a VMA
+    csd_paddr -= PHYS_OFFSET;
+
+    dbg(DBG_CORE, "mapping in core specific data to 0x%p\n", (void *)csd_paddr);
+    pt_map_range(pt_get(), csd_paddr, CSD_START, CSD_END, PT_PRESENT | PT_WRITE,
+                 PT_PRESENT | PT_WRITE);
+    tlb_flush_all();
+
+    memset((void *)CSD_START, 0, CSD_END - CSD_START);
+
+    curcore.kc_id = apic_current_id();
+    curcore.kc_queue = NULL;
+    curcore.kc_csdpaddr = csd_paddr;
+
+    intr_init();
+    gdt_init();
+
+    apic_enable();
+    time_init();
+    sched_init();
+
+    void *stack = page_alloc();
+    KASSERT(stack != NULL);
+
+    context_setup_raw(&curcore.kc_ctx, core_switch, stack, PAGE_SIZE, pt_get());
+}
+
+void __attribute__((used)) smp_processor_entry()
+{
+    core_init();
+    dbg_force(DBG_CORE, "started C%ld!\n", curcore.kc_id);
+    smp_processor_count++;
+
+    KASSERT(!intr_enabled());
+    preemption_disable();
+    proc_idleproc_init();
+    context_make_active(&curcore.kc_ctx);
+}
+
+/*
+ * Prepare for SMP by copying the real-mode trampoline code into the
+ * first 1mb of memory.
+ */
+void smp_init()
+{
+    NOT_YET_IMPLEMENTED("SMP: ***none***");
+}
+
+// Intel Vol. 3A 10-11, 10.4.7.3
+static void smp_start_processor(uint8_t apic_id)
+{
+    // TODO: not necessarily true that apic_id == processor_id
+    dbg_force(DBG_CORE, "Booting C%d\n", apic_id);
+
+    memcpy((void *)PHYS_OFFSET, (void *)smp_initialization_start,
+           smp_initialization_size);
+
+    // First, send a INIT IPI
+
+    long prev_count = smp_processor_count;
+    apic_start_processor(apic_id, 0);
+
+    while (smp_processor_count == prev_count)
+        ;
+}
+
+static long smp_stop_processor(regs_t *regs)
+{
+    char buf[2048];
+    time_stats(buf, sizeof(buf));
+
+    dbg_force(DBG_CORE, "\n%s\nhalted cleanly!\n\n", buf);
+
+    __asm__ volatile("cli; hlt;");
+
+    return 0;
+}