diff options
Diffstat (limited to 'arch/powerpc/sysdev/dcr.c')
| -rw-r--r-- | arch/powerpc/sysdev/dcr.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/dcr.c b/arch/powerpc/sysdev/dcr.c new file mode 100644 index 000000000000..dffeeaeca1d9 --- /dev/null +++ b/arch/powerpc/sysdev/dcr.c @@ -0,0 +1,137 @@ +/* + * (c) Copyright 2006 Benjamin Herrenschmidt, IBM Corp. + * <benh@kernel.crashing.org> + * + * This program 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 2 of the License, or + * (at your option) any later version. + * + * This program 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 this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#undef DEBUG + +#include <linux/kernel.h> +#include <asm/prom.h> +#include <asm/dcr.h> + +unsigned int dcr_resource_start(struct device_node *np, unsigned int index) +{ + unsigned int ds; + const u32 *dr = get_property(np, "dcr-reg", &ds); + + if (dr == NULL || ds & 1 || index >= (ds / 8)) + return 0; + + return dr[index * 2]; +} + +unsigned int dcr_resource_len(struct device_node *np, unsigned int index) +{ + unsigned int ds; + const u32 *dr = get_property(np, "dcr-reg", &ds); + + if (dr == NULL || ds & 1 || index >= (ds / 8)) + return 0; + + return dr[index * 2 + 1]; +} + +#ifndef CONFIG_PPC_DCR_NATIVE + +static struct device_node * find_dcr_parent(struct device_node * node) +{ + struct device_node *par, *tmp; + const u32 *p; + + for (par = of_node_get(node); par;) { + if (get_property(par, "dcr-controller", NULL)) + break; + p = get_property(par, "dcr-parent", NULL); + tmp = par; + if (p == NULL) + par = of_get_parent(par); + else + par = of_find_node_by_phandle(*p); + of_node_put(tmp); + } + return par; +} + +u64 of_translate_dcr_address(struct device_node *dev, + unsigned int dcr_n, + unsigned int *out_stride) +{ + struct device_node *dp; + const u32 *p; + unsigned int stride; + u64 ret; + + dp = find_dcr_parent(dev); + if (dp == NULL) + return OF_BAD_ADDR; + + /* Stride is not properly defined yet, default to 0x10 for Axon */ + p = get_property(dp, "dcr-mmio-stride", NULL); + stride = (p == NULL) ? 0x10 : *p; + + /* XXX FIXME: Which property name is to use of the 2 following ? */ + p = get_property(dp, "dcr-mmio-range", NULL); + if (p == NULL) + p = get_property(dp, "dcr-mmio-space", NULL); + if (p == NULL) + return OF_BAD_ADDR; + + /* Maybe could do some better range checking here */ + ret = of_translate_address(dp, p); + if (ret != OF_BAD_ADDR) + ret += (u64)(stride) * (u64)dcr_n; + if (out_stride) + *out_stride = stride; + return ret; +} + +dcr_host_t dcr_map(struct device_node *dev, unsigned int dcr_n, + unsigned int dcr_c) +{ + dcr_host_t ret = { .token = NULL, .stride = 0 }; + u64 addr; + + pr_debug("dcr_map(%s, 0x%x, 0x%x)\n", + dev->full_name, dcr_n, dcr_c); + + addr = of_translate_dcr_address(dev, dcr_n, &ret.stride); + pr_debug("translates to addr: 0x%lx, stride: 0x%x\n", + addr, ret.stride); + if (addr == OF_BAD_ADDR) + return ret; + pr_debug("mapping 0x%x bytes\n", dcr_c * ret.stride); + ret.token = ioremap(addr, dcr_c * ret.stride); + if (ret.token == NULL) + return ret; + pr_debug("mapped at 0x%p -> base is 0x%p\n", + ret.token, ret.token - dcr_n * ret.stride); + ret.token -= dcr_n * ret.stride; + return ret; +} + +void dcr_unmap(dcr_host_t host, unsigned int dcr_n, unsigned int dcr_c) +{ + dcr_host_t h = host; + + if (h.token == NULL) + return; + h.token -= dcr_n * h.stride; + iounmap(h.token); + h.token = NULL; +} + +#endif /* !defined(CONFIG_PPC_DCR_NATIVE) */ |
