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Diffstat (limited to '')
| -rw-r--r-- | arch/powerpc/sysdev/dcr.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/dcr.c b/arch/powerpc/sysdev/dcr.c new file mode 100644 index 000000000..22991e112 --- /dev/null +++ b/arch/powerpc/sysdev/dcr.c @@ -0,0 +1,222 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * (c) Copyright 2006 Benjamin Herrenschmidt, IBM Corp. + * <benh@kernel.crashing.org> + */ + +#undef DEBUG + +#include <linux/kernel.h> +#include <linux/export.h> +#include <asm/prom.h> +#include <asm/dcr.h> + +#ifdef CONFIG_PPC_DCR_MMIO +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 (of_get_property(par, "dcr-controller", NULL)) + break; + p = of_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; +} +#endif + +#if defined(CONFIG_PPC_DCR_NATIVE) && defined(CONFIG_PPC_DCR_MMIO) + +bool dcr_map_ok_generic(dcr_host_t host) +{ + if (host.type == DCR_HOST_NATIVE) + return dcr_map_ok_native(host.host.native); + else if (host.type == DCR_HOST_MMIO) + return dcr_map_ok_mmio(host.host.mmio); + else + return false; +} +EXPORT_SYMBOL_GPL(dcr_map_ok_generic); + +dcr_host_t dcr_map_generic(struct device_node *dev, + unsigned int dcr_n, + unsigned int dcr_c) +{ + dcr_host_t host; + struct device_node *dp; + const char *prop; + + host.type = DCR_HOST_INVALID; + + dp = find_dcr_parent(dev); + if (dp == NULL) + return host; + + prop = of_get_property(dp, "dcr-access-method", NULL); + + pr_debug("dcr_map_generic(dcr-access-method = %s)\n", prop); + + if (!strcmp(prop, "native")) { + host.type = DCR_HOST_NATIVE; + host.host.native = dcr_map_native(dev, dcr_n, dcr_c); + } else if (!strcmp(prop, "mmio")) { + host.type = DCR_HOST_MMIO; + host.host.mmio = dcr_map_mmio(dev, dcr_n, dcr_c); + } + + of_node_put(dp); + return host; +} +EXPORT_SYMBOL_GPL(dcr_map_generic); + +void dcr_unmap_generic(dcr_host_t host, unsigned int dcr_c) +{ + if (host.type == DCR_HOST_NATIVE) + dcr_unmap_native(host.host.native, dcr_c); + else if (host.type == DCR_HOST_MMIO) + dcr_unmap_mmio(host.host.mmio, dcr_c); + else /* host.type == DCR_HOST_INVALID */ + WARN_ON(true); +} +EXPORT_SYMBOL_GPL(dcr_unmap_generic); + +u32 dcr_read_generic(dcr_host_t host, unsigned int dcr_n) +{ + if (host.type == DCR_HOST_NATIVE) + return dcr_read_native(host.host.native, dcr_n); + else if (host.type == DCR_HOST_MMIO) + return dcr_read_mmio(host.host.mmio, dcr_n); + else /* host.type == DCR_HOST_INVALID */ + WARN_ON(true); + return 0; +} +EXPORT_SYMBOL_GPL(dcr_read_generic); + +void dcr_write_generic(dcr_host_t host, unsigned int dcr_n, u32 value) +{ + if (host.type == DCR_HOST_NATIVE) + dcr_write_native(host.host.native, dcr_n, value); + else if (host.type == DCR_HOST_MMIO) + dcr_write_mmio(host.host.mmio, dcr_n, value); + else /* host.type == DCR_HOST_INVALID */ + WARN_ON(true); +} +EXPORT_SYMBOL_GPL(dcr_write_generic); + +#endif /* defined(CONFIG_PPC_DCR_NATIVE) && defined(CONFIG_PPC_DCR_MMIO) */ + +unsigned int dcr_resource_start(const struct device_node *np, + unsigned int index) +{ + unsigned int ds; + const u32 *dr = of_get_property(np, "dcr-reg", &ds); + + if (dr == NULL || ds & 1 || index >= (ds / 8)) + return 0; + + return dr[index * 2]; +} +EXPORT_SYMBOL_GPL(dcr_resource_start); + +unsigned int dcr_resource_len(const struct device_node *np, unsigned int index) +{ + unsigned int ds; + const u32 *dr = of_get_property(np, "dcr-reg", &ds); + + if (dr == NULL || ds & 1 || index >= (ds / 8)) + return 0; + + return dr[index * 2 + 1]; +} +EXPORT_SYMBOL_GPL(dcr_resource_len); + +#ifdef CONFIG_PPC_DCR_MMIO + +static 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 = OF_BAD_ADDR; + + dp = find_dcr_parent(dev); + if (dp == NULL) + return OF_BAD_ADDR; + + /* Stride is not properly defined yet, default to 0x10 for Axon */ + p = of_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 = of_get_property(dp, "dcr-mmio-range", NULL); + if (p == NULL) + p = of_get_property(dp, "dcr-mmio-space", NULL); + if (p == NULL) + goto done; + + /* 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; + + done: + of_node_put(dp); + return ret; +} + +dcr_host_mmio_t dcr_map_mmio(struct device_node *dev, + unsigned int dcr_n, + unsigned int dcr_c) +{ + dcr_host_mmio_t ret = { .token = NULL, .stride = 0, .base = dcr_n }; + u64 addr; + + pr_debug("dcr_map(%pOF, 0x%x, 0x%x)\n", + dev, dcr_n, dcr_c); + + addr = of_translate_dcr_address(dev, dcr_n, &ret.stride); + pr_debug("translates to addr: 0x%llx, stride: 0x%x\n", + (unsigned long long) 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; +} +EXPORT_SYMBOL_GPL(dcr_map_mmio); + +void dcr_unmap_mmio(dcr_host_mmio_t host, unsigned int dcr_c) +{ + dcr_host_mmio_t h = host; + + if (h.token == NULL) + return; + h.token += host.base * h.stride; + iounmap(h.token); + h.token = NULL; +} +EXPORT_SYMBOL_GPL(dcr_unmap_mmio); + +#endif /* defined(CONFIG_PPC_DCR_MMIO) */ + +#ifdef CONFIG_PPC_DCR_NATIVE +DEFINE_SPINLOCK(dcr_ind_lock); +EXPORT_SYMBOL_GPL(dcr_ind_lock); +#endif /* defined(CONFIG_PPC_DCR_NATIVE) */ + |