Updated hello.c from putch() to printf().

[pdp11-modern-c] / pdp11 / pdp11_mmu.c

// (c) 2020 Aaron Taylor <ataylor at subgeniuskitty dot com>
// See License.txt file for copyright and license details.

#include <stdint.h>
#include "pdp11_register.h"
#include "pdp11_slu.h"

void
init_mmu(void)
{

    /*
     * First populate the relocation registers, all zero since we want an
     * identity mapping, except the highest page that we remap to the physical MMIO
     * range.
     */
    SET(KISAR0,PAR_PAF,0000000);
    SET(KISAR1,PAR_PAF,0000000);
    SET(KISAR2,PAR_PAF,0000000);
    SET(KISAR3,PAR_PAF,0000000);
    SET(KISAR4,PAR_PAF,0000000);
    SET(KISAR5,PAR_PAF,0000000);
    SET(KISAR6,PAR_PAF,0000000);
    SET(KISAR7,PAR_PAF,0177600);

    /*
     * Now populate the page descriptor registers. See EK-KDJ1B-UG page 1-19
     * for details of each field.
     */
    uint16_t data = 0;
    SET(data,PDR_BYPASCACHE,0);
    SET(data,PDR_PAGELEN,0177);
    SET(data,PDR_PAGEWRITEN,0);
    SET(data,PDR_EXPANDDIR,0);
    SET(data,PDR_ACCESSCTRL,03);

    KISDR0 = data;
    KISDR1 = data;
    KISDR2 = data;
    KISDR3 = data;
    KISDR4 = data;
    KISDR5 = data;
    KISDR6 = data;
    KISDR7 = data;

    /*
     * Enable the MMU with a 22-bit mapping.
     */
    SET(MMR3,MMR3_KRNSPLTID,0);
    SET(MMR3,MMR3_EN_22BIT,1);
    SET(MMR0,MMR0_EN_MMU,1);
}