diff options
Diffstat (limited to 'grub-core/bus/fdt.c')
| -rw-r--r-- | grub-core/bus/fdt.c | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/grub-core/bus/fdt.c b/grub-core/bus/fdt.c new file mode 100644 index 0000000..135da49 --- /dev/null +++ b/grub-core/bus/fdt.c @@ -0,0 +1,256 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2016 Free Software Foundation, Inc. + * + * 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/fdtbus.h> +#include <grub/fdt.h> +#include <grub/term.h> + +static const void *dtb; +static grub_size_t root_address_cells, root_size_cells; +/* Pointer to this symbol signals invalid mapping. */ +char grub_fdtbus_invalid_mapping[1]; + +struct grub_fdtbus_dev *devs; +struct grub_fdtbus_driver *drivers; + +int +grub_fdtbus_is_compatible (const char *compat_string, + const struct grub_fdtbus_dev *dev) +{ + grub_size_t compatible_size; + const char *compatible = grub_fdt_get_prop (dtb, dev->node, "compatible", + &compatible_size); + if (!compatible) + return 0; + const char *compatible_end = compatible + compatible_size; + while (compatible < compatible_end) + { + if (grub_strcmp (compat_string, compatible) == 0) + return 1; + compatible += grub_strlen (compatible) + 1; + } + return 0; +} + +static void +fdtbus_scan (struct grub_fdtbus_dev *parent) +{ + int node; + for (node = grub_fdt_first_node (dtb, parent ? parent->node : 0); node >= 0; + node = grub_fdt_next_node (dtb, node)) + { + struct grub_fdtbus_dev *dev; + struct grub_fdtbus_driver *driver; + dev = grub_zalloc (sizeof (*dev)); + if (!dev) + { + grub_print_error (); + return; + } + dev->node = node; + dev->next = devs; + dev->parent = parent; + devs = dev; + FOR_LIST_ELEMENTS(driver, drivers) + if (!dev->driver && grub_fdtbus_is_compatible (driver->compatible, dev)) + { + grub_dprintf ("fdtbus", "Attaching %s\n", driver->compatible); + if (driver->attach (dev) == GRUB_ERR_NONE) + { + grub_dprintf ("fdtbus", "Attached %s\n", driver->compatible); + dev->driver = driver; + break; + } + grub_print_error (); + } + fdtbus_scan (dev); + } +} + +void +grub_fdtbus_register (struct grub_fdtbus_driver *driver) +{ + struct grub_fdtbus_dev *dev; + grub_dprintf ("fdtbus", "Registering %s\n", driver->compatible); + grub_list_push (GRUB_AS_LIST_P (&drivers), + GRUB_AS_LIST (driver)); + for (dev = devs; dev; dev = dev->next) + if (!dev->driver && grub_fdtbus_is_compatible (driver->compatible, dev)) + { + grub_dprintf ("fdtbus", "Attaching %s (%p)\n", driver->compatible, dev); + if (driver->attach (dev) == GRUB_ERR_NONE) + { + grub_dprintf ("fdtbus", "Attached %s\n", driver->compatible); + dev->driver = driver; + } + grub_print_error (); + } +} + +void +grub_fdtbus_unregister (struct grub_fdtbus_driver *driver) +{ + grub_list_remove (GRUB_AS_LIST (driver)); + struct grub_fdtbus_dev *dev; + for (dev = devs; dev; dev = dev->next) + if (dev->driver == driver) + { + if (driver->detach) + driver->detach(dev); + dev->driver = 0; + } +} + +void +grub_fdtbus_init (const void *dtb_in, grub_size_t size) +{ + if (!dtb_in || grub_fdt_check_header (dtb_in, size) < 0) + grub_fatal ("invalid FDT"); + dtb = dtb_in; + const grub_uint32_t *prop = grub_fdt_get_prop (dtb, 0, "#address-cells", 0); + if (prop) + root_address_cells = grub_be_to_cpu32 (*prop); + else + root_address_cells = 1; + + prop = grub_fdt_get_prop (dtb, 0, "#size-cells", 0); + if (prop) + root_size_cells = grub_be_to_cpu32 (*prop); + else + root_size_cells = 1; + + fdtbus_scan (0); +} + +static int +get_address_cells (const struct grub_fdtbus_dev *dev) +{ + const grub_uint32_t *prop; + if (!dev) + return root_address_cells; + prop = grub_fdt_get_prop (dtb, dev->node, "#address-cells", 0); + if (prop) + return grub_be_to_cpu32 (*prop); + return 1; +} + +static int +get_size_cells (const struct grub_fdtbus_dev *dev) +{ + const grub_uint32_t *prop; + if (!dev) + return root_size_cells; + prop = grub_fdt_get_prop (dtb, dev->node, "#size-cells", 0); + if (prop) + return grub_be_to_cpu32 (*prop); + return 1; +} + +static grub_uint64_t +get64 (const grub_uint32_t *reg, grub_size_t cells) +{ + grub_uint64_t val = 0; + if (cells >= 1) + val = grub_be_to_cpu32 (reg[cells - 1]); + if (cells >= 2) + val |= ((grub_uint64_t) grub_be_to_cpu32 (reg[cells - 2])) << 32; + return val; +} + +static volatile void * +translate (const struct grub_fdtbus_dev *dev, const grub_uint32_t *reg) +{ + volatile void *ret; + const grub_uint32_t *ranges; + grub_size_t ranges_size, cells_per_mapping; + grub_size_t parent_address_cells, child_address_cells, child_size_cells; + grub_size_t nmappings, i; + if (dev == 0) + { + grub_uint64_t val; + val = get64 (reg, root_address_cells); + if (sizeof (void *) == 4 && (val >> 32)) + return grub_fdtbus_invalid_mapping; + return (void *) (grub_addr_t) val; + } + ranges = grub_fdt_get_prop (dtb, dev->node, "ranges", &ranges_size); + if (!ranges) + return grub_fdtbus_invalid_mapping; + if (ranges_size == 0) + return translate (dev->parent, reg); + parent_address_cells = get_address_cells (dev->parent); + child_address_cells = get_address_cells (dev); + child_size_cells = get_size_cells (dev); + cells_per_mapping = parent_address_cells + child_address_cells + child_size_cells; + nmappings = ranges_size / 4 / cells_per_mapping; + for (i = 0; i < nmappings; i++) + { + const grub_uint32_t *child_addr = &ranges[i * cells_per_mapping]; + const grub_uint32_t *parent_addr = child_addr + child_address_cells; + grub_uint64_t child_size = get64 (parent_addr + parent_address_cells, child_size_cells); + + if (child_address_cells > 2 && grub_memcmp (reg, child_addr, (child_address_cells - 2) * 4) != 0) + continue; + if (get64 (reg, child_address_cells) < get64 (child_addr, child_address_cells)) + continue; + + grub_uint64_t offset = get64 (reg, child_address_cells) - get64 (child_addr, child_address_cells); + if (offset >= child_size) + continue; + + ret = translate (dev->parent, parent_addr); + if (grub_fdtbus_is_mapping_valid (ret)) + ret = (volatile char *) ret + offset; + return ret; + } + return grub_fdtbus_invalid_mapping; +} + +volatile void * +grub_fdtbus_map_reg (const struct grub_fdtbus_dev *dev, int regno, grub_size_t *size) +{ + grub_size_t address_cells, size_cells; + address_cells = get_address_cells (dev->parent); + size_cells = get_size_cells (dev->parent); + const grub_uint32_t *reg = grub_fdt_get_prop (dtb, dev->node, "reg", 0); + if (size && size_cells) + *size = reg[(address_cells + size_cells) * regno + address_cells]; + if (size && !size_cells) + *size = 0; + return translate (dev->parent, reg + (address_cells + size_cells) * regno); +} + +const char * +grub_fdtbus_get_name (const struct grub_fdtbus_dev *dev) +{ + return grub_fdt_get_nodename (dtb, dev->node); +} + +const void * +grub_fdtbus_get_prop (const struct grub_fdtbus_dev *dev, + const char *name, + grub_uint32_t *len) +{ + return grub_fdt_get_prop (dtb, dev->node, name, len); +} + +const void * +grub_fdtbus_get_fdt (void) +{ + return dtb; +} |