mmio.c

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/* SPDX-License-Identifier: GPL-2.0-only */
 
#include <assert.h>
#include <device/mmio.h>
 
/* Helper functions for various MMIO access patterns. */
 
void buffer_from_fifo32(void *buffer, size_t size, void *fifo,
                        int fifo_stride, int fifo_width)
{
        u8 *p = buffer;
        int i, j;
 
        assert(fifo_width > 0 && fifo_width <= sizeof(u32) &&
               fifo_stride % sizeof(u32) == 0);
 
        for (i = 0; i < size; i += fifo_width, fifo += fifo_stride) {
                u32 val = read32(fifo);
                for (j = 0; j < MIN(size - i, fifo_width); j++)
                        *p++ = (u8)(val >> (j * 8));
        }
}
 
void buffer_to_fifo32_prefix(const void *buffer, u32 prefix, int prefsz, size_t size,
                             void *fifo, int fifo_stride, int fifo_width)
{
        const u8 *p = buffer;
        int i, j = prefsz;
 
        assert(fifo_width > 0 && fifo_width <= sizeof(u32) &&
               fifo_stride % sizeof(u32) == 0 && prefsz <= fifo_width);
 
        uint32_t val = prefix;
        for (i = 0; i < size; i += fifo_width, fifo += fifo_stride) {
                for (; j < MIN(size - i, fifo_width); j++)
                        val |= *p++ << (j * 8);
                write32(fifo, val);
                val = 0;
                j = 0;
        }
 
}