root/arch/arm/mm/proc-mohawk.S
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 *  linux/arch/arm/mm/proc-mohawk.S: MMU functions for Marvell PJ1 core
 *
 *  PJ1 (codename Mohawk) is a hybrid of the xscale3 and Marvell's own core.
 *
 *  Heavily based on proc-arm926.S and proc-xsc3.S
 */

#include <linux/linkage.h>
#include <linux/init.h>
#include <linux/cfi_types.h>
#include <linux/pgtable.h>
#include <asm/assembler.h>
#include <asm/hwcap.h>
#include <asm/pgtable-hwdef.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include "proc-macros.S"

/*
 * This is the maximum size of an area which will be flushed.  If the
 * area is larger than this, then we flush the whole cache.
 */
#define CACHE_DLIMIT    32768

/*
 * The cache line size of the L1 D cache.
 */
#define CACHE_DLINESIZE 32

/*
 * cpu_mohawk_proc_init()
 */
SYM_TYPED_FUNC_START(cpu_mohawk_proc_init)
        ret     lr
SYM_FUNC_END(cpu_mohawk_proc_init)

/*
 * cpu_mohawk_proc_fin()
 */
SYM_TYPED_FUNC_START(cpu_mohawk_proc_fin)
        mrc     p15, 0, r0, c1, c0, 0           @ ctrl register
        bic     r0, r0, #0x1800                 @ ...iz...........
        bic     r0, r0, #0x0006                 @ .............ca.
        mcr     p15, 0, r0, c1, c0, 0           @ disable caches
        ret     lr
SYM_FUNC_END(cpu_mohawk_proc_fin)

/*
 * cpu_mohawk_reset(loc)
 *
 * Perform a soft reset of the system.  Put the CPU into the
 * same state as it would be if it had been reset, and branch
 * to what would be the reset vector.
 *
 * loc: location to jump to for soft reset
 *
 * (same as arm926)
 */
        .align  5
        .pushsection    .idmap.text, "ax"
SYM_TYPED_FUNC_START(cpu_mohawk_reset)
        mov     ip, #0
        mcr     p15, 0, ip, c7, c7, 0           @ invalidate I,D caches
        mcr     p15, 0, ip, c7, c10, 4          @ drain WB
        mcr     p15, 0, ip, c8, c7, 0           @ invalidate I & D TLBs
        mrc     p15, 0, ip, c1, c0, 0           @ ctrl register
        bic     ip, ip, #0x0007                 @ .............cam
        bic     ip, ip, #0x1100                 @ ...i...s........
        mcr     p15, 0, ip, c1, c0, 0           @ ctrl register
        ret     r0
SYM_FUNC_END(cpu_mohawk_reset)
        .popsection

/*
 * cpu_mohawk_do_idle()
 *
 * Called with IRQs disabled
 */
        .align  5
SYM_TYPED_FUNC_START(cpu_mohawk_do_idle)
        mov     r0, #0
        mcr     p15, 0, r0, c7, c10, 4          @ drain write buffer
        mcr     p15, 0, r0, c7, c0, 4           @ wait for interrupt
        ret     lr
SYM_FUNC_END(cpu_mohawk_do_idle)

/*
 *      flush_icache_all()
 *
 *      Unconditionally clean and invalidate the entire icache.
 */
SYM_TYPED_FUNC_START(mohawk_flush_icache_all)
        mov     r0, #0
        mcr     p15, 0, r0, c7, c5, 0           @ invalidate I cache
        ret     lr
SYM_FUNC_END(mohawk_flush_icache_all)

/*
 *      flush_user_cache_all()
 *
 *      Clean and invalidate all cache entries in a particular
 *      address space.
 */
SYM_FUNC_ALIAS(mohawk_flush_user_cache_all, mohawk_flush_kern_cache_all)

/*
 *      flush_kern_cache_all()
 *
 *      Clean and invalidate the entire cache.
 */
SYM_TYPED_FUNC_START(mohawk_flush_kern_cache_all)
        mov     r2, #VM_EXEC
        mov     ip, #0
__flush_whole_cache:
        mcr     p15, 0, ip, c7, c14, 0          @ clean & invalidate all D cache
        tst     r2, #VM_EXEC
        mcrne   p15, 0, ip, c7, c5, 0           @ invalidate I cache
        mcrne   p15, 0, ip, c7, c10, 0          @ drain write buffer
        ret     lr
SYM_FUNC_END(mohawk_flush_kern_cache_all)

/*
 *      flush_user_cache_range(start, end, flags)
 *
 *      Clean and invalidate a range of cache entries in the
 *      specified address range.
 *
 *      - start - start address (inclusive)
 *      - end   - end address (exclusive)
 *      - flags - vm_flags describing address space
 *
 * (same as arm926)
 */
SYM_TYPED_FUNC_START(mohawk_flush_user_cache_range)
        mov     ip, #0
        sub     r3, r1, r0                      @ calculate total size
        cmp     r3, #CACHE_DLIMIT
        bgt     __flush_whole_cache
1:      tst     r2, #VM_EXEC
        mcr     p15, 0, r0, c7, c14, 1          @ clean and invalidate D entry
        mcrne   p15, 0, r0, c7, c5, 1           @ invalidate I entry
        add     r0, r0, #CACHE_DLINESIZE
        mcr     p15, 0, r0, c7, c14, 1          @ clean and invalidate D entry
        mcrne   p15, 0, r0, c7, c5, 1           @ invalidate I entry
        add     r0, r0, #CACHE_DLINESIZE
        cmp     r0, r1
        blo     1b
        tst     r2, #VM_EXEC
        mcrne   p15, 0, ip, c7, c10, 4          @ drain WB
        ret     lr
SYM_FUNC_END(mohawk_flush_user_cache_range)

/*
 *      coherent_kern_range(start, end)
 *
 *      Ensure coherency between the Icache and the Dcache in the
 *      region described by start, end.  If you have non-snooping
 *      Harvard caches, you need to implement this function.
 *
 *      - start - virtual start address
 *      - end   - virtual end address
 */
SYM_TYPED_FUNC_START(mohawk_coherent_kern_range)
#ifdef CONFIG_CFI /* Fallthrough if !CFI */
        b       mohawk_coherent_user_range
#endif
SYM_FUNC_END(mohawk_coherent_kern_range)

/*
 *      coherent_user_range(start, end)
 *
 *      Ensure coherency between the Icache and the Dcache in the
 *      region described by start, end.  If you have non-snooping
 *      Harvard caches, you need to implement this function.
 *
 *      - start - virtual start address
 *      - end   - virtual end address
 *
 * (same as arm926)
 */
SYM_TYPED_FUNC_START(mohawk_coherent_user_range)
        bic     r0, r0, #CACHE_DLINESIZE - 1
1:      mcr     p15, 0, r0, c7, c10, 1          @ clean D entry
        mcr     p15, 0, r0, c7, c5, 1           @ invalidate I entry
        add     r0, r0, #CACHE_DLINESIZE
        cmp     r0, r1
        blo     1b
        mcr     p15, 0, r0, c7, c10, 4          @ drain WB
        mov     r0, #0
        ret     lr
SYM_FUNC_END(mohawk_coherent_user_range)

/*
 *      flush_kern_dcache_area(void *addr, size_t size)
 *
 *      Ensure no D cache aliasing occurs, either with itself or
 *      the I cache
 *
 *      - addr  - kernel address
 *      - size  - region size
 */
SYM_TYPED_FUNC_START(mohawk_flush_kern_dcache_area)
        add     r1, r0, r1
1:      mcr     p15, 0, r0, c7, c14, 1          @ clean+invalidate D entry
        add     r0, r0, #CACHE_DLINESIZE
        cmp     r0, r1
        blo     1b
        mov     r0, #0
        mcr     p15, 0, r0, c7, c5, 0           @ invalidate I cache
        mcr     p15, 0, r0, c7, c10, 4          @ drain WB
        ret     lr
SYM_FUNC_END(mohawk_flush_kern_dcache_area)

/*
 *      dma_inv_range(start, end)
 *
 *      Invalidate (discard) the specified virtual address range.
 *      May not write back any entries.  If 'start' or 'end'
 *      are not cache line aligned, those lines must be written
 *      back.
 *
 *      - start - virtual start address
 *      - end   - virtual end address
 *
 * (same as v4wb)
 */
mohawk_dma_inv_range:
        tst     r0, #CACHE_DLINESIZE - 1
        mcrne   p15, 0, r0, c7, c10, 1          @ clean D entry
        tst     r1, #CACHE_DLINESIZE - 1
        mcrne   p15, 0, r1, c7, c10, 1          @ clean D entry
        bic     r0, r0, #CACHE_DLINESIZE - 1
1:      mcr     p15, 0, r0, c7, c6, 1           @ invalidate D entry
        add     r0, r0, #CACHE_DLINESIZE
        cmp     r0, r1
        blo     1b
        mcr     p15, 0, r0, c7, c10, 4          @ drain WB
        ret     lr

/*
 *      dma_clean_range(start, end)
 *
 *      Clean the specified virtual address range.
 *
 *      - start - virtual start address
 *      - end   - virtual end address
 *
 * (same as v4wb)
 */
mohawk_dma_clean_range:
        bic     r0, r0, #CACHE_DLINESIZE - 1
1:      mcr     p15, 0, r0, c7, c10, 1          @ clean D entry
        add     r0, r0, #CACHE_DLINESIZE
        cmp     r0, r1
        blo     1b
        mcr     p15, 0, r0, c7, c10, 4          @ drain WB
        ret     lr

/*
 *      dma_flush_range(start, end)
 *
 *      Clean and invalidate the specified virtual address range.
 *
 *      - start - virtual start address
 *      - end   - virtual end address
 */
SYM_TYPED_FUNC_START(mohawk_dma_flush_range)
        bic     r0, r0, #CACHE_DLINESIZE - 1
1:
        mcr     p15, 0, r0, c7, c14, 1          @ clean+invalidate D entry
        add     r0, r0, #CACHE_DLINESIZE
        cmp     r0, r1
        blo     1b
        mcr     p15, 0, r0, c7, c10, 4          @ drain WB
        ret     lr
SYM_FUNC_END(mohawk_dma_flush_range)

/*
 *      dma_map_area(start, size, dir)
 *      - start - kernel virtual start address
 *      - size  - size of region
 *      - dir   - DMA direction
 */
SYM_TYPED_FUNC_START(mohawk_dma_map_area)
        add     r1, r1, r0
        cmp     r2, #DMA_TO_DEVICE
        beq     mohawk_dma_clean_range
        bcs     mohawk_dma_inv_range
        b       mohawk_dma_flush_range
SYM_FUNC_END(mohawk_dma_map_area)

/*
 *      dma_unmap_area(start, size, dir)
 *      - start - kernel virtual start address
 *      - size  - size of region
 *      - dir   - DMA direction
 */
SYM_TYPED_FUNC_START(mohawk_dma_unmap_area)
        ret     lr
SYM_FUNC_END(mohawk_dma_unmap_area)

SYM_TYPED_FUNC_START(cpu_mohawk_dcache_clean_area)
1:      mcr     p15, 0, r0, c7, c10, 1          @ clean D entry
        add     r0, r0, #CACHE_DLINESIZE
        subs    r1, r1, #CACHE_DLINESIZE
        bhi     1b
        mcr     p15, 0, r0, c7, c10, 4          @ drain WB
        ret     lr
SYM_FUNC_END(cpu_mohawk_dcache_clean_area)

/*
 * cpu_mohawk_switch_mm(pgd)
 *
 * Set the translation base pointer to be as described by pgd.
 *
 * pgd: new page tables
 */
        .align  5
SYM_TYPED_FUNC_START(cpu_mohawk_switch_mm)
        mov     ip, #0
        mcr     p15, 0, ip, c7, c14, 0          @ clean & invalidate all D cache
        mcr     p15, 0, ip, c7, c5, 0           @ invalidate I cache
        mcr     p15, 0, ip, c7, c10, 4          @ drain WB
        orr     r0, r0, #0x18                   @ cache the page table in L2
        mcr     p15, 0, r0, c2, c0, 0           @ load page table pointer
        mcr     p15, 0, ip, c8, c7, 0           @ invalidate I & D TLBs
        ret     lr
SYM_FUNC_END(cpu_mohawk_switch_mm)

/*
 * cpu_mohawk_set_pte_ext(ptep, pte, ext)
 *
 * Set a PTE and flush it out
 */
        .align  5
SYM_TYPED_FUNC_START(cpu_mohawk_set_pte_ext)
#ifdef CONFIG_MMU
        armv3_set_pte_ext
        mov     r0, r0
        mcr     p15, 0, r0, c7, c10, 1          @ clean D entry
        mcr     p15, 0, r0, c7, c10, 4          @ drain WB
        ret     lr
#endif
SYM_FUNC_END(cpu_mohawk_set_pte_ext)

.globl  cpu_mohawk_suspend_size
.equ    cpu_mohawk_suspend_size, 4 * 6
#ifdef CONFIG_ARM_CPU_SUSPEND
SYM_TYPED_FUNC_START(cpu_mohawk_do_suspend)
        stmfd   sp!, {r4 - r9, lr}
        mrc     p14, 0, r4, c6, c0, 0   @ clock configuration, for turbo mode
        mrc     p15, 0, r5, c15, c1, 0  @ CP access reg
        mrc     p15, 0, r6, c13, c0, 0  @ PID
        mrc     p15, 0, r7, c3, c0, 0   @ domain ID
        mrc     p15, 0, r8, c1, c0, 1   @ auxiliary control reg
        mrc     p15, 0, r9, c1, c0, 0   @ control reg
        bic     r4, r4, #2              @ clear frequency change bit
        stmia   r0, {r4 - r9}           @ store cp regs
        ldmia   sp!, {r4 - r9, pc}
SYM_FUNC_END(cpu_mohawk_do_suspend)

SYM_TYPED_FUNC_START(cpu_mohawk_do_resume)
        ldmia   r0, {r4 - r9}           @ load cp regs
        mov     ip, #0
        mcr     p15, 0, ip, c7, c7, 0   @ invalidate I & D caches, BTB
        mcr     p15, 0, ip, c7, c10, 4  @ drain write (&fill) buffer
        mcr     p15, 0, ip, c7, c5, 4   @ flush prefetch buffer
        mcr     p15, 0, ip, c8, c7, 0   @ invalidate I & D TLBs
        mcr     p14, 0, r4, c6, c0, 0   @ clock configuration, turbo mode.
        mcr     p15, 0, r5, c15, c1, 0  @ CP access reg
        mcr     p15, 0, r6, c13, c0, 0  @ PID
        mcr     p15, 0, r7, c3, c0, 0   @ domain ID
        orr     r1, r1, #0x18           @ cache the page table in L2
        mcr     p15, 0, r1, c2, c0, 0   @ translation table base addr
        mcr     p15, 0, r8, c1, c0, 1   @ auxiliary control reg
        mov     r0, r9                  @ control register
        b       cpu_resume_mmu
SYM_FUNC_END(cpu_mohawk_do_resume)
#endif

        .type   __mohawk_setup, #function
__mohawk_setup:
        mov     r0, #0
        mcr     p15, 0, r0, c7, c7              @ invalidate I,D caches
        mcr     p15, 0, r0, c7, c10, 4          @ drain write buffer
        mcr     p15, 0, r0, c8, c7              @ invalidate I,D TLBs
        orr     r4, r4, #0x18                   @ cache the page table in L2
        mcr     p15, 0, r4, c2, c0, 0           @ load page table pointer

        mov     r0, #0                          @ don't allow CP access
        mcr     p15, 0, r0, c15, c1, 0          @ write CP access register

        adr     r5, mohawk_crval
        ldmia   r5, {r5, r6}
        mrc     p15, 0, r0, c1, c0              @ get control register
        bic     r0, r0, r5
        orr     r0, r0, r6
        ret     lr

        .size   __mohawk_setup, . - __mohawk_setup

        /*
         *  R
         * .RVI ZFRS BLDP WCAM
         * .011 1001 ..00 0101
         *
         */
        .type   mohawk_crval, #object
mohawk_crval:
        crval   clear=0x00007f3f, mmuset=0x00003905, ucset=0x00001134

        __INITDATA

        @ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
        define_processor_functions mohawk, dabort=v5t_early_abort, pabort=legacy_pabort

        .section ".rodata"

        string  cpu_arch_name, "armv5te"
        string  cpu_elf_name, "v5"
        string  cpu_mohawk_name, "Marvell 88SV331x"

        .align

        .section ".proc.info.init", "a"

        .type   __88sv331x_proc_info,#object
__88sv331x_proc_info:
        .long   0x56158000                      @ Marvell 88SV331x (MOHAWK)
        .long   0xfffff000
        .long   PMD_TYPE_SECT | \
                PMD_SECT_BUFFERABLE | \
                PMD_SECT_CACHEABLE | \
                PMD_BIT4 | \
                PMD_SECT_AP_WRITE | \
                PMD_SECT_AP_READ
        .long   PMD_TYPE_SECT | \
                PMD_BIT4 | \
                PMD_SECT_AP_WRITE | \
                PMD_SECT_AP_READ
        initfn  __mohawk_setup, __88sv331x_proc_info
        .long   cpu_arch_name
        .long   cpu_elf_name
        .long   HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
        .long   cpu_mohawk_name
        .long   mohawk_processor_functions
        .long   v4wbi_tlb_fns
        .long   v4wb_user_fns
        .long   mohawk_cache_fns
        .size   __88sv331x_proc_info, . - __88sv331x_proc_info