/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 2006-2008, Juniper Networks, Inc. * Copyright (c) 2008 Semihalf, Rafal Czubak * Copyright (c) 2009 The FreeBSD Foundation * All rights reserved. * * Portions of this software were developed by Semihalf * under sponsorship from the FreeBSD Foundation. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "opt_platform.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "ofw_bus_if.h" #include "lbc.h" #ifdef DEBUG #define debugf(fmt, args...) do { printf("%s(): ", __func__); \ printf(fmt,##args); } while (0) #else #define debugf(fmt, args...) #endif static MALLOC_DEFINE(M_LBC, "localbus", "localbus devices information"); static int lbc_probe(device_t); static int lbc_attach(device_t); static int lbc_shutdown(device_t); static int lbc_map_resource(device_t, device_t, struct resource *, struct resource_map_request *, struct resource_map *); static int lbc_unmap_resource(device_t, device_t, struct resource *, struct resource_map *map); static int lbc_activate_resource(device_t bus, device_t child, struct resource *r); static int lbc_deactivate_resource(device_t bus, device_t child, struct resource *r); static struct rman *lbc_get_rman(device_t, int, u_int); static struct resource *lbc_alloc_resource(device_t, device_t, int, int *, rman_res_t, rman_res_t, rman_res_t, u_int); static int lbc_adjust_resource(device_t, device_t, struct resource *, rman_res_t, rman_res_t); static int lbc_print_child(device_t, device_t); static int lbc_release_resource(device_t, device_t, struct resource *); static const struct ofw_bus_devinfo *lbc_get_devinfo(device_t, device_t); /* * Bus interface definition */ static device_method_t lbc_methods[] = { /* Device interface */ DEVMETHOD(device_probe, lbc_probe), DEVMETHOD(device_attach, lbc_attach), DEVMETHOD(device_shutdown, lbc_shutdown), /* Bus interface */ DEVMETHOD(bus_print_child, lbc_print_child), DEVMETHOD(bus_setup_intr, bus_generic_setup_intr), DEVMETHOD(bus_teardown_intr, NULL), DEVMETHOD(bus_get_rman, lbc_get_rman), DEVMETHOD(bus_alloc_resource, lbc_alloc_resource), DEVMETHOD(bus_adjust_resource, lbc_adjust_resource), DEVMETHOD(bus_release_resource, lbc_release_resource), DEVMETHOD(bus_activate_resource, lbc_activate_resource), DEVMETHOD(bus_deactivate_resource, lbc_deactivate_resource), DEVMETHOD(bus_map_resource, lbc_map_resource), DEVMETHOD(bus_unmap_resource, lbc_unmap_resource), /* OFW bus interface */ DEVMETHOD(ofw_bus_get_devinfo, lbc_get_devinfo), DEVMETHOD(ofw_bus_get_compat, ofw_bus_gen_get_compat), DEVMETHOD(ofw_bus_get_model, ofw_bus_gen_get_model), DEVMETHOD(ofw_bus_get_name, ofw_bus_gen_get_name), DEVMETHOD(ofw_bus_get_node, ofw_bus_gen_get_node), DEVMETHOD(ofw_bus_get_type, ofw_bus_gen_get_type), { 0, 0 } }; static driver_t lbc_driver = { "lbc", lbc_methods, sizeof(struct lbc_softc) }; EARLY_DRIVER_MODULE(lbc, ofwbus, lbc_driver, 0, 0, BUS_PASS_BUS); /* * Calculate address mask used by OR(n) registers. Use memory region size to * determine mask value. The size must be a power of two and within the range * of 32KB - 4GB. Otherwise error code is returned. Value representing * 4GB size can be passed as 0xffffffff. */ static uint32_t lbc_address_mask(uint32_t size) { int n = 15; if (size == ~0) return (0); while (n < 32) { if (size == (1U << n)) break; n++; } if (n == 32) return (EINVAL); return (0xffff8000 << (n - 15)); } static void lbc_banks_unmap(struct lbc_softc *sc) { int r; r = 0; while (r < LBC_DEV_MAX) { if (sc->sc_range[r].size == 0) return; pmap_unmapdev((void *)sc->sc_range[r].kva, sc->sc_range[r].size); law_disable(OCP85XX_TGTIF_LBC, sc->sc_range[r].addr, sc->sc_range[r].size); r++; } } static int lbc_banks_map(struct lbc_softc *sc) { vm_paddr_t end, start; vm_size_t size; u_int i, r, ranges, s; int error; bzero(sc->sc_range, sizeof(sc->sc_range)); /* * Determine number of discontiguous address ranges to program. */ ranges = 0; for (i = 0; i < LBC_DEV_MAX; i++) { size = sc->sc_banks[i].size; if (size == 0) continue; start = sc->sc_banks[i].addr; for (r = 0; r < ranges; r++) { /* Avoid wrap-around bugs. */ end = sc->sc_range[r].addr - 1 + sc->sc_range[r].size; if (start > 0 && end == start - 1) { sc->sc_range[r].size += size; break; } /* Avoid wrap-around bugs. */ end = start - 1 + size; if (sc->sc_range[r].addr > 0 && end == sc->sc_range[r].addr - 1) { sc->sc_range[r].addr = start; sc->sc_range[r].size += size; break; } } if (r == ranges) { /* New range; add using insertion sort */ r = 0; while (r < ranges && sc->sc_range[r].addr < start) r++; for (s = ranges; s > r; s--) sc->sc_range[s] = sc->sc_range[s-1]; sc->sc_range[r].addr = start; sc->sc_range[r].size = size; ranges++; } } /* * Ranges are sorted so quickly go over the list to merge ranges * that grew toward each other while building the ranges. */ r = 0; while (r < ranges - 1) { end = sc->sc_range[r].addr + sc->sc_range[r].size; if (end != sc->sc_range[r+1].addr) { r++; continue; } sc->sc_range[r].size += sc->sc_range[r+1].size; for (s = r + 1; s < ranges - 1; s++) sc->sc_range[s] = sc->sc_range[s+1]; bzero(&sc->sc_range[s], sizeof(sc->sc_range[s])); ranges--; } /* * Configure LAW for the LBC ranges and map the physical memory * range into KVA. */ for (r = 0; r < ranges; r++) { start = sc->sc_range[r].addr; size = sc->sc_range[r].size; error = law_enable(OCP85XX_TGTIF_LBC, start, size); if (error) return (error); sc->sc_range[r].kva = (vm_offset_t)pmap_mapdev(start, size); } /* XXX: need something better here? */ if (ranges == 0) return (EINVAL); /* Assign KVA to banks based on the enclosing range. */ for (i = 0; i < LBC_DEV_MAX; i++) { size = sc->sc_banks[i].size; if (size == 0) continue; start = sc->sc_banks[i].addr; for (r = 0; r < ranges; r++) { end = sc->sc_range[r].addr - 1 + sc->sc_range[r].size; if (start >= sc->sc_range[r].addr && start - 1 + size <= end) break; } if (r < ranges) { sc->sc_banks[i].kva = sc->sc_range[r].kva + (start - sc->sc_range[r].addr); } } return (0); } static int lbc_banks_enable(struct lbc_softc *sc) { uint32_t size; uint32_t regval; int error, i; for (i = 0; i < LBC_DEV_MAX; i++) { size = sc->sc_banks[i].size; if (size == 0) continue; /* * Compute and program BR value. */ regval = sc->sc_banks[i].addr; switch (sc->sc_banks[i].width) { case 8: regval |= (1 << 11); break; case 16: regval |= (2 << 11); break; case 32: regval |= (3 << 11); break; default: error = EINVAL; goto fail; } regval |= (sc->sc_banks[i].decc << 9); regval |= (sc->sc_banks[i].wp << 8); regval |= (sc->sc_banks[i].msel << 5); regval |= (sc->sc_banks[i].atom << 2); regval |= 1; bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_BR(i), regval); /* * Compute and program OR value. */ regval = lbc_address_mask(size); switch (sc->sc_banks[i].msel) { case LBCRES_MSEL_GPCM: /* TODO Add flag support for option registers */ regval |= 0x0ff7; break; case LBCRES_MSEL_FCM: /* TODO Add flag support for options register */ regval |= 0x0796; break; case LBCRES_MSEL_UPMA: case LBCRES_MSEL_UPMB: case LBCRES_MSEL_UPMC: printf("UPM mode not supported yet!"); error = ENOSYS; goto fail; } bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_OR(i), regval); } return (0); fail: lbc_banks_unmap(sc); return (error); } static void fdt_lbc_fixup(phandle_t node, struct lbc_softc *sc, struct lbc_devinfo *di) { pcell_t width; int bank; if (OF_getprop(node, "bank-width", (void *)&width, sizeof(width)) <= 0) return; bank = di->di_bank; if (sc->sc_banks[bank].size == 0) return; /* Express width in bits. */ sc->sc_banks[bank].width = width * 8; } static int fdt_lbc_reg_decode(phandle_t node, struct lbc_softc *sc, struct lbc_devinfo *di) { rman_res_t start, end, count; pcell_t *reg, *regptr; pcell_t addr_cells, size_cells; int tuple_size, tuples; int i, j, rv, bank; if (fdt_addrsize_cells(OF_parent(node), &addr_cells, &size_cells) != 0) return (ENXIO); tuple_size = sizeof(pcell_t) * (addr_cells + size_cells); tuples = OF_getencprop_alloc_multi(node, "reg", tuple_size, (void **)®); debugf("addr_cells = %d, size_cells = %d\n", addr_cells, size_cells); debugf("tuples = %d, tuple size = %d\n", tuples, tuple_size); if (tuples <= 0) /* No 'reg' property in this node. */ return (0); regptr = reg; for (i = 0; i < tuples; i++) { bank = fdt_data_get((void *)reg, 1); di->di_bank = bank; reg += 1; /* Get address/size. */ start = count = 0; for (j = 0; j < addr_cells - 1; j++) { start <<= 32; start |= reg[j]; } for (j = 0; j < size_cells; j++) { count <<= 32; count |= reg[addr_cells + j - 1]; } reg += addr_cells - 1 + size_cells; /* Calculate address range relative to VA base. */ start = sc->sc_banks[bank].kva + start; end = start + count - 1; debugf("reg addr bank = %d, start = %jx, end = %jx, " "count = %jx\n", bank, start, end, count); /* Use bank (CS) cell as rid. */ resource_list_add(&di->di_res, SYS_RES_MEMORY, bank, start, end, count); } rv = 0; OF_prop_free(regptr); return (rv); } static void lbc_intr(void *arg) { struct lbc_softc *sc = arg; uint32_t ltesr; ltesr = bus_space_read_4(sc->sc_bst, sc->sc_bsh, LBC85XX_LTESR); sc->sc_ltesr = ltesr; bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_LTESR, ltesr); wakeup(sc->sc_dev); } static int lbc_probe(device_t dev) { if (!(ofw_bus_is_compatible(dev, "fsl,lbc") || ofw_bus_is_compatible(dev, "fsl,elbc"))) return (ENXIO); device_set_desc(dev, "Freescale Local Bus Controller"); return (BUS_PROBE_DEFAULT); } static int lbc_attach(device_t dev) { struct lbc_softc *sc; struct lbc_devinfo *di; struct rman *rm; uintmax_t offset, size; vm_paddr_t start; device_t cdev; phandle_t node, child; pcell_t *ranges, *rangesptr; int tuple_size, tuples; int par_addr_cells; int bank, error, i, j; sc = device_get_softc(dev); sc->sc_dev = dev; sc->sc_mrid = 0; sc->sc_mres = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->sc_mrid, RF_ACTIVE); if (sc->sc_mres == NULL) return (ENXIO); sc->sc_bst = rman_get_bustag(sc->sc_mres); sc->sc_bsh = rman_get_bushandle(sc->sc_mres); for (bank = 0; bank < LBC_DEV_MAX; bank++) { bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_BR(bank), 0); bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_OR(bank), 0); } /* * Initialize configuration register: * - enable Local Bus * - set data buffer control signal function * - disable parity byte select * - set ECC parity type * - set bus monitor timing and timer prescale */ bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_LBCR, 0); /* * Initialize clock ratio register: * - disable PLL bypass mode * - configure LCLK delay cycles for the assertion of LALE * - set system clock divider */ bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_LCRR, 0x00030008); bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_LTEDR, 0); bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_LTESR, ~0); bus_space_write_4(sc->sc_bst, sc->sc_bsh, LBC85XX_LTEIR, 0x64080001); sc->sc_irid = 0; sc->sc_ires = bus_alloc_resource_any(dev, SYS_RES_IRQ, &sc->sc_irid, RF_ACTIVE | RF_SHAREABLE); if (sc->sc_ires != NULL) { error = bus_setup_intr(dev, sc->sc_ires, INTR_TYPE_MISC | INTR_MPSAFE, NULL, lbc_intr, sc, &sc->sc_icookie); if (error) { device_printf(dev, "could not activate interrupt\n"); bus_release_resource(dev, SYS_RES_IRQ, sc->sc_irid, sc->sc_ires); sc->sc_ires = NULL; } } sc->sc_ltesr = ~0; rangesptr = NULL; rm = &sc->sc_rman; rm->rm_type = RMAN_ARRAY; rm->rm_descr = "Local Bus Space"; error = rman_init(rm); if (error) goto fail; error = rman_manage_region(rm, rm->rm_start, rm->rm_end); if (error) { rman_fini(rm); goto fail; } /* * Process 'ranges' property. */ node = ofw_bus_get_node(dev); if ((fdt_addrsize_cells(node, &sc->sc_addr_cells, &sc->sc_size_cells)) != 0) { error = ENXIO; goto fail; } par_addr_cells = fdt_parent_addr_cells(node); if (par_addr_cells > 2) { device_printf(dev, "unsupported parent #addr-cells\n"); error = ERANGE; goto fail; } tuple_size = sizeof(pcell_t) * (sc->sc_addr_cells + par_addr_cells + sc->sc_size_cells); tuples = OF_getencprop_alloc_multi(node, "ranges", tuple_size, (void **)&ranges); if (tuples < 0) { device_printf(dev, "could not retrieve 'ranges' property\n"); error = ENXIO; goto fail; } rangesptr = ranges; debugf("par addr_cells = %d, addr_cells = %d, size_cells = %d, " "tuple_size = %d, tuples = %d\n", par_addr_cells, sc->sc_addr_cells, sc->sc_size_cells, tuple_size, tuples); start = 0; size = 0; for (i = 0; i < tuples; i++) { /* The first cell is the bank (chip select) number. */ bank = fdt_data_get(ranges, 1); if (bank < 0 || bank > LBC_DEV_MAX) { device_printf(dev, "bank out of range: %d\n", bank); error = ERANGE; goto fail; } ranges += 1; /* * Remaining cells of the child address define offset into * this CS. */ offset = 0; for (j = 0; j < sc->sc_addr_cells - 1; j++) { offset <<= sizeof(pcell_t) * 8; offset |= *ranges; ranges++; } /* Parent bus start address of this bank. */ start = 0; for (j = 0; j < par_addr_cells; j++) { start <<= sizeof(pcell_t) * 8; start |= *ranges; ranges++; } size = fdt_data_get((void *)ranges, sc->sc_size_cells); ranges += sc->sc_size_cells; debugf("bank = %d, start = %jx, size = %jx\n", bank, (uintmax_t)start, size); sc->sc_banks[bank].addr = start + offset; sc->sc_banks[bank].size = size; /* * Attributes for the bank. * * XXX Note there are no DT bindings defined for them at the * moment, so we need to provide some defaults. */ sc->sc_banks[bank].width = 16; sc->sc_banks[bank].msel = LBCRES_MSEL_GPCM; sc->sc_banks[bank].decc = LBCRES_DECC_DISABLED; sc->sc_banks[bank].atom = LBCRES_ATOM_DISABLED; sc->sc_banks[bank].wp = 0; } /* * Initialize mem-mappings for the LBC banks (i.e. chip selects). */ error = lbc_banks_map(sc); if (error) goto fail; /* * Walk the localbus and add direct subordinates as our children. */ for (child = OF_child(node); child != 0; child = OF_peer(child)) { di = malloc(sizeof(*di), M_LBC, M_WAITOK | M_ZERO); if (ofw_bus_gen_setup_devinfo(&di->di_ofw, child) != 0) { free(di, M_LBC); device_printf(dev, "could not set up devinfo\n"); continue; } resource_list_init(&di->di_res); if (fdt_lbc_reg_decode(child, sc, di)) { device_printf(dev, "could not process 'reg' " "property\n"); ofw_bus_gen_destroy_devinfo(&di->di_ofw); free(di, M_LBC); continue; } fdt_lbc_fixup(child, sc, di); /* Add newbus device for this FDT node */ cdev = device_add_child(dev, NULL, DEVICE_UNIT_ANY); if (cdev == NULL) { device_printf(dev, "could not add child: %s\n", di->di_ofw.obd_name); resource_list_free(&di->di_res); ofw_bus_gen_destroy_devinfo(&di->di_ofw); free(di, M_LBC); continue; } debugf("added child name='%s', node=%x\n", di->di_ofw.obd_name, child); device_set_ivars(cdev, di); } /* * Enable the LBC. */ lbc_banks_enable(sc); OF_prop_free(rangesptr); return (bus_generic_attach(dev)); fail: OF_prop_free(rangesptr); bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_mrid, sc->sc_mres); return (error); } static int lbc_shutdown(device_t dev) { /* TODO */ return(0); } static struct rman * lbc_get_rman(device_t bus, int type, u_int flags) { struct lbc_softc *sc; sc = device_get_softc(bus); switch (type) { case SYS_RES_MEMORY: return (&sc->sc_rman); default: return (NULL); } } static struct resource * lbc_alloc_resource(device_t bus, device_t child, int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags) { struct lbc_devinfo *di; struct resource_list_entry *rle; /* We only support default allocations. */ if (!RMAN_IS_DEFAULT_RANGE(start, end)) return (NULL); if (type == SYS_RES_IRQ) return (bus_alloc_resource(bus, type, rid, start, end, count, flags)); /* * Request for the default allocation with a given rid: use resource * list stored in the local device info. */ if ((di = device_get_ivars(child)) == NULL) return (NULL); if (type == SYS_RES_IOPORT) type = SYS_RES_MEMORY; /* * XXX: We are supposed to return a value to the user, so this * doesn't seem right. */ rid = &di->di_bank; rle = resource_list_find(&di->di_res, type, *rid); if (rle == NULL) { device_printf(bus, "no default resources for " "rid = %d, type = %d\n", *rid, type); return (NULL); } start = rle->start; count = rle->count; end = start + count - 1; return (bus_generic_rman_alloc_resource(bus, child, type, rid, start, end, count, flags)); } static int lbc_print_child(device_t dev, device_t child) { struct lbc_devinfo *di; struct resource_list *rl; int rv; di = device_get_ivars(child); rl = &di->di_res; rv = 0; rv += bus_print_child_header(dev, child); rv += resource_list_print_type(rl, "mem", SYS_RES_MEMORY, "%#jx"); rv += resource_list_print_type(rl, "irq", SYS_RES_IRQ, "%jd"); rv += bus_print_child_footer(dev, child); return (rv); } static int lbc_adjust_resource(device_t dev, device_t child, struct resource *r, rman_res_t start, rman_res_t end) { switch (rman_get_type(r)) { case SYS_RES_MEMORY: return (bus_generic_rman_adjust_resource(dev, child, r, start, end)); case SYS_RES_IRQ: return (bus_generic_adjust_resource(dev, child, r, start, end)); default: return (EINVAL); } } static int lbc_release_resource(device_t dev, device_t child, struct resource *res) { switch (rman_get_type(res)) { case SYS_RES_MEMORY: return (bus_generic_rman_release_resource(dev, child, res)); case SYS_RES_IRQ: return (bus_generic_release_resource(dev, child, res)); default: return (EINVAL); } } static int lbc_activate_resource(device_t bus, device_t child, struct resource *r) { switch (rman_get_type(r)) { case SYS_RES_MEMORY: return (bus_generic_rman_activate_resource(bus, child, r)); case SYS_RES_IRQ: return (bus_generic_activate_resource(bus, child, r)); default: return (EINVAL); } } static int lbc_deactivate_resource(device_t bus, device_t child, struct resource *r) { switch (rman_get_type(r)) { case SYS_RES_MEMORY: return (bus_generic_rman_deactivate_resource(bus, child, r)); case SYS_RES_IRQ: return (bus_generic_deactivate_resource(bus, child, r)); default: return (EINVAL); } } static int lbc_map_resource(device_t bus, device_t child, struct resource *r, struct resource_map_request *argsp, struct resource_map *map) { struct resource_map_request args; rman_res_t length, start; int error; /* Resources must be active to be mapped. */ if (!(rman_get_flags(r) & RF_ACTIVE)) return (ENXIO); /* Mappings are only supported on I/O and memory resources. */ switch (rman_get_type(r)) { case SYS_RES_IOPORT: case SYS_RES_MEMORY: break; default: return (EINVAL); } resource_init_map_request(&args); error = resource_validate_map_request(r, argsp, &args, &start, &length); if (error) return (error); map->r_bustag = &bs_be_tag; map->r_bushandle = start; map->r_size = length; map->r_vaddr = NULL; return (0); } static int lbc_unmap_resource(device_t bus, device_t child, struct resource *r, struct resource_map *map) { /* Mappings are only supported on I/O and memory resources. */ switch (rman_get_type(r)) { case SYS_RES_IOPORT: case SYS_RES_MEMORY: break; default: return (EINVAL); } return (0); } static const struct ofw_bus_devinfo * lbc_get_devinfo(device_t bus, device_t child) { struct lbc_devinfo *di; di = device_get_ivars(child); return (&di->di_ofw); } void lbc_write_reg(device_t child, u_int off, uint32_t val) { device_t dev; struct lbc_softc *sc; dev = device_get_parent(child); if (off >= 0x1000) { device_printf(dev, "%s(%s): invalid offset %#x\n", __func__, device_get_nameunit(child), off); return; } sc = device_get_softc(dev); if (off == LBC85XX_LTESR && sc->sc_ltesr != ~0u) { sc->sc_ltesr ^= (val & sc->sc_ltesr); return; } if (off == LBC85XX_LTEATR && (val & 1) == 0) sc->sc_ltesr = ~0u; bus_space_write_4(sc->sc_bst, sc->sc_bsh, off, val); } uint32_t lbc_read_reg(device_t child, u_int off) { device_t dev; struct lbc_softc *sc; uint32_t val; dev = device_get_parent(child); if (off >= 0x1000) { device_printf(dev, "%s(%s): invalid offset %#x\n", __func__, device_get_nameunit(child), off); return (~0U); } sc = device_get_softc(dev); if (off == LBC85XX_LTESR && sc->sc_ltesr != ~0U) val = sc->sc_ltesr; else val = bus_space_read_4(sc->sc_bst, sc->sc_bsh, off); return (val); }