patch-2.2.16 linux/arch/alpha/lib/callback_init.c

• Lines: 84
• Date: Wed Jun 7 14:26:42 2000
• Orig file: v2.2.15/linux/arch/alpha/lib/callback_init.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN v2.2.15/linux/arch/alpha/lib/callback_init.c linux/arch/alpha/lib/callback_init.c
@@ -0,0 +1,83 @@
+/*
+ *      arch/alpha/lib/callback_init.c
+ */
+
+#include <asm/page.h>
+#include <asm/hwrpb.h>
+#include <asm/console.h>
+#include <asm/pgtable.h>
+#include <asm/init.h>
+
+#include "../kernel/proto.h"
+
+int callback_init_done = 0;
+
+/* This is the SRM version.  Maybe there will be a DBM version. */
+
+void * __init callback_init(void * kernel_end)
+{
+	int i, j;
+	unsigned long vaddr = CONSOLE_REMAP_START;
+	struct crb_struct * crb;
+	pgd_t * pgd = pgd_offset_k(vaddr);
+	pmd_t * pmd;
+	void * two_pte_pages;
+
+	/* Always page align the end of the kernel. */
+	kernel_end = (void *)
+	  (((unsigned long)kernel_end + ~PAGE_MASK) & PAGE_MASK);
+
+	if (!alpha_using_srm) {
+		switch_to_system_map();
+		return kernel_end;
+	}
+
+	/* Allocate some memory for the pages. */
+	two_pte_pages = kernel_end;
+	kernel_end = two_pte_pages + 2*PAGE_SIZE;
+	memset(two_pte_pages, 0, 2*PAGE_SIZE);
+
+	/* Starting at the HWRPB, locate the CRB. */
+	crb = (struct crb_struct *)((char *)hwrpb + hwrpb->crb_offset);
+
+	/* Tell the console whither the console is to be remapped. */
+	if (srm_fixup(vaddr, (unsigned long)hwrpb))
+		__halt();		/* "We're boned."  --Bender */
+
+	/* Edit the procedure descriptors for DISPATCH and FIXUP. */
+	crb->dispatch_va = (struct procdesc_struct *)
+		(vaddr + (unsigned long)crb->dispatch_va - crb->map[0].va);
+	crb->fixup_va = (struct procdesc_struct *)
+		(vaddr + (unsigned long)crb->fixup_va - crb->map[0].va);
+
+	switch_to_system_map();
+
+	/*
+	 * Set up the first and second level PTEs for console callbacks.
+	 * There is an assumption here that only one of each is needed,
+	 * and this allows for 8MB.  Currently (late 1999), big consoles
+	 * are still under 3MB.
+	 */
+	pgd_set(pgd, (pmd_t *)two_pte_pages);
+	pmd = pmd_offset(pgd, vaddr);
+	pmd_set(pmd, (pte_t *)(two_pte_pages + PAGE_SIZE));
+
+	/*
+	 * Set up the third level PTEs and update the virtual addresses
+	 * of the CRB entries.
+	 */
+	for (i = 0; i < crb->map_entries; ++i) {
+		unsigned long paddr = crb->map[i].pa;
+		crb->map[i].va = vaddr;
+		for (j = 0; j < crb->map[i].count; ++j) {
+			set_pte(pte_offset(pmd, vaddr),
+				mk_pte_phys(paddr, PAGE_KERNEL));
+			paddr += PAGE_SIZE;
+			vaddr += PAGE_SIZE;
+		}
+	}
+
+	callback_init_done = 1;
+	return kernel_end;
+}
+