| /* |
| * GRUB -- GRand Unified Bootloader |
| * |
| * Copyright (C) 2012 Google Inc. |
| * Copyright (C) 2016 Free Software Foundation, Inc. |
| * |
| * This is based on depthcharge code. |
| * |
| * GRUB is free software: you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation, either version 3 of the License, or |
| * (at your option) any later version. |
| * |
| * GRUB is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with GRUB. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <grub/mm.h> |
| #include <grub/time.h> |
| #include <grub/misc.h> |
| #include <grub/fdtbus.h> |
| #include <grub/machine/kernel.h> |
| |
| static grub_err_t |
| spi_send (const struct grub_fdtbus_dev *dev, const void *data, grub_size_t sz) |
| { |
| const grub_uint8_t *ptr = data, *end = ptr + sz; |
| volatile grub_uint32_t *spi = grub_fdtbus_map_reg (dev, 0, 0); |
| spi[2] = 0; |
| spi[1] = sz - 1; |
| spi[0] = ((1 << 18) | spi[0]) & ~(1 << 19); |
| spi[2] = 1; |
| while (ptr < end) |
| { |
| while (spi[9] & 2); |
| spi[256] = *ptr++; |
| } |
| while (spi[9] & 1); |
| return GRUB_ERR_NONE; |
| } |
| |
| static grub_err_t |
| spi_receive (const struct grub_fdtbus_dev *dev, void *data, grub_size_t sz) |
| { |
| grub_uint8_t *ptr = data, *end = ptr + sz; |
| volatile grub_uint32_t *spi = grub_fdtbus_map_reg (dev, 0, 0); |
| spi[2] = 0; |
| spi[1] = sz - 1; |
| spi[0] = ((1 << 19) | spi[0]) & ~(1 << 18); |
| spi[2] = 1; |
| while (ptr < end) |
| { |
| while (spi[9] & 8); |
| *ptr++ = spi[512]; |
| } |
| while (spi[9] & 1); |
| return GRUB_ERR_NONE; |
| } |
| |
| static grub_err_t |
| spi_start (const struct grub_fdtbus_dev *dev) |
| { |
| volatile grub_uint32_t *spi = grub_fdtbus_map_reg (dev, 0, 0); |
| spi[3] = 1; |
| return GRUB_ERR_NONE; |
| } |
| |
| static void |
| spi_stop (const struct grub_fdtbus_dev *dev) |
| { |
| volatile grub_uint32_t *spi = grub_fdtbus_map_reg (dev, 0, 0); |
| spi[3] = 0; |
| } |
| |
| static grub_err_t |
| spi_attach(const struct grub_fdtbus_dev *dev) |
| { |
| if (!grub_fdtbus_is_mapping_valid (grub_fdtbus_map_reg (dev, 0, 0))) |
| return GRUB_ERR_IO; |
| |
| return GRUB_ERR_NONE; |
| } |
| |
| static struct grub_fdtbus_driver spi = |
| { |
| .compatible = "rockchip,rk3288-spi", |
| .attach = spi_attach, |
| .send = spi_send, |
| .receive = spi_receive, |
| .start = spi_start, |
| .stop = spi_stop, |
| }; |
| |
| void |
| grub_rk3288_spi_init (void) |
| { |
| grub_fdtbus_register (&spi); |
| } |