/*
 * (C) Copyright 2002
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */

#include <common.h>
#include <asm/system.h>
#include <asm/cache.h>
#include <linux/compiler.h>

#if !(defined(CONFIG_SYS_ICACHE_OFF) && defined(CONFIG_SYS_DCACHE_OFF))

DECLARE_GLOBAL_DATA_PTR;

__weak void arm_init_before_mmu(void)
{
}

__weak void arm_init_domains(void)
{
}

static void cp_delay (void)
{
        volatile int i;

        /* copro seems to need some delay between reading and writing */
        for (i = 0; i < 100; i++)
                nop();
        asm volatile("" : : : "memory");
}

void set_section_dcache(int section, enum dcache_option option)
{
#ifdef CONFIG_ARMV7_LPAE
        u64 *page_table = (u64 *)gd->arch.tlb_addr;
        /* Need to set the access flag to not fault */
        u64 value = TTB_SECT_AP | TTB_SECT_AF;
#else
        u32 *page_table = (u32 *)gd->arch.tlb_addr;
        u32 value = TTB_SECT_AP;
#endif

        /* Add the page offset */
        value |= ((u32)section << MMU_SECTION_SHIFT);

        /* Add caching bits */
        value |= option;

        /* Set PTE */
        page_table[section] = value;
}

__weak void mmu_page_table_flush(unsigned long start, unsigned long stop)
{
        debug("%s: Warning: not implemented\n", __func__);
}

void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
                                     enum dcache_option option)
{
        u32 *page_table = (u32 *)gd->arch.tlb_addr;
        unsigned long upto, end;

        end = ALIGN(start + size, MMU_SECTION_SIZE) >> MMU_SECTION_SHIFT;
        start = start >> MMU_SECTION_SHIFT;
        debug("%s: start=%pa, size=%zu, option=%d\n", __func__, &start, size,
              option);
        for (upto = start; upto < end; upto++)
                set_section_dcache(upto, option);
        mmu_page_table_flush((u32)&page_table[start], (u32)&page_table[end]);
}

__weak void dram_bank_mmu_setup(int bank)
{
        bd_t *bd = gd->bd;
        int     i;

        debug("%s: bank: %d\n", __func__, bank);
        for (i = bd->bi_dram[bank].start >> MMU_SECTION_SHIFT;
             i < (bd->bi_dram[bank].start >> MMU_SECTION_SHIFT) +
                 (bd->bi_dram[bank].size >> MMU_SECTION_SHIFT);
             i++) {
#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
                set_section_dcache(i, DCACHE_WRITETHROUGH);
#elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
                set_section_dcache(i, DCACHE_WRITEALLOC);
#else
                set_section_dcache(i, DCACHE_WRITEBACK);
#endif
        }
}

/* to activate the MMU we need to set up virtual memory: use 1M areas */
static inline void mmu_setup(void)
{
        int i;
        u32 reg;

        arm_init_before_mmu();
        /* Set up an identity-mapping for all 4GB, rw for everyone */
        for (i = 0; i < ((4096ULL * 1024 * 1024) >> MMU_SECTION_SHIFT); i++)
                set_section_dcache(i, DCACHE_OFF);

        for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
                dram_bank_mmu_setup(i);
        }

#ifdef CONFIG_ARMV7_LPAE
        /* Set up 4 PTE entries pointing to our 4 1GB page tables */
        for (i = 0; i < 4; i++) {
                u64 *page_table = (u64 *)(gd->arch.tlb_addr + (4096 * 4));
                u64 tpt = gd->arch.tlb_addr + (4096 * i);
                page_table[i] = tpt | TTB_PAGETABLE;
        }

        reg = TTBCR_EAE;
#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
        reg |= TTBCR_ORGN0_WT | TTBCR_IRGN0_WT;
#elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
        reg |= TTBCR_ORGN0_WBWA | TTBCR_IRGN0_WBWA;
#else
        reg |= TTBCR_ORGN0_WBNWA | TTBCR_IRGN0_WBNWA;
#endif

        if (is_hyp()) {
                /* Set HCTR to enable LPAE */
                asm volatile("mcr p15, 4, %0, c2, c0, 2"
                        : : "r" (reg) : "memory");
                /* Set HTTBR0 */
                asm volatile("mcrr p15, 4, %0, %1, c2"
                        :
                        : "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
                        : "memory");
                /* Set HMAIR */
                asm volatile("mcr p15, 4, %0, c10, c2, 0"
                        : : "r" (MEMORY_ATTRIBUTES) : "memory");
        } else {
                /* Set TTBCR to enable LPAE */
                asm volatile("mcr p15, 0, %0, c2, c0, 2"
                        : : "r" (reg) : "memory");
                /* Set 64-bit TTBR0 */
                asm volatile("mcrr p15, 0, %0, %1, c2"
                        :
                        : "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
                        : "memory");
                /* Set MAIR */
                asm volatile("mcr p15, 0, %0, c10, c2, 0"
                        : : "r" (MEMORY_ATTRIBUTES) : "memory");
        }
#elif defined(CONFIG_CPU_V7)
        /* Set TTBR0 */
        reg = gd->arch.tlb_addr & TTBR0_BASE_ADDR_MASK;
#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
        reg |= TTBR0_RGN_WT | TTBR0_IRGN_WT;
#elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
        reg |= TTBR0_RGN_WBWA | TTBR0_IRGN_WBWA;
#else
        reg |= TTBR0_RGN_WB | TTBR0_IRGN_WB;
#endif
        asm volatile("mcr p15, 0, %0, c2, c0, 0"
                     : : "r" (reg) : "memory");
#else
        /* Copy the page table address to cp15 */
        asm volatile("mcr p15, 0, %0, c2, c0, 0"
                     : : "r" (gd->arch.tlb_addr) : "memory");
#endif
        /* Set the access control to all-supervisor */
        asm volatile("mcr p15, 0, %0, c3, c0, 0"
                     : : "r" (~0));

        arm_init_domains();

        /* and enable the mmu */
        reg = get_cr(); /* get control reg. */
        cp_delay();
        set_cr(reg | CR_M);
}

static int mmu_enabled(void)
{
        return get_cr() & CR_M;
}

/* cache_bit must be either CR_I or CR_C */
static void cache_enable(uint32_t cache_bit)
{
        uint32_t reg;

        /* The data cache is not active unless the mmu is enabled too */
        if ((cache_bit == CR_C) && !mmu_enabled())
                mmu_setup();
        reg = get_cr(); /* get control reg. */
        cp_delay();
        set_cr(reg | cache_bit);
}

/* cache_bit must be either CR_I or CR_C */
static void cache_disable(uint32_t cache_bit)
{
        uint32_t reg;

        reg = get_cr();
        cp_delay();

        if (cache_bit == CR_C) {
                /* if cache isn;t enabled no need to disable */
                if ((reg & CR_C) != CR_C)
                        return;
                /* if disabling data cache, disable mmu too */
                cache_bit |= CR_M;
        }
        reg = get_cr();
        cp_delay();
        if (cache_bit == (CR_C | CR_M))
                flush_dcache_all();
        set_cr(reg & ~cache_bit);
}
#endif

#ifdef CONFIG_SYS_ICACHE_OFF
void icache_enable (void)
{
        return;
}

void icache_disable (void)
{
        return;
}

int icache_status (void)
{
        return 0;                                       /* always off */
}
#else
void icache_enable(void)
{
        cache_enable(CR_I);
}

void icache_disable(void)
{
        cache_disable(CR_I);
}

int icache_status(void)
{
        return (get_cr() & CR_I) != 0;
}
#endif

#ifdef CONFIG_SYS_DCACHE_OFF
void dcache_enable (void)
{
        return;
}

void dcache_disable (void)
{
        return;
}

int dcache_status (void)
{
        return 0;                                       /* always off */
}
#else
void dcache_enable(void)
{
        cache_enable(CR_C);
}

void dcache_disable(void)
{
        cache_disable(CR_C);
}

int dcache_status(void)
{
        return (get_cr() & CR_C) != 0;
}
#endif