| Message ID | 20190809173449.20126-2-marek.vasut@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | None | expand |
On Fri, Aug 09, 2019 at 07:34:49PM +0200, marek.vasut@gmail.com wrote: > From: Oza Pawandeep <oza.oza@broadcom.com> > > current device framework and OF framework integration assumes > dma-ranges in a way where memory-mapped devices define their > dma-ranges. (child-bus-address, parent-bus-address, length). > > of_dma_configure is specifically written to take care of memory > mapped devices. but no implementation exists for pci to take > care of pcie based memory ranges. > > for e.g. iproc based SOCs and other SOCs(such as rcar) have PCI > world dma-ranges. > dma-ranges = <0x43000000 0x00 0x00 0x00 0x00 0x80 0x00>; > > this patch fixes the following problems of_dma_get_range. > 1) return of wrong size as 0. > 2) not handling absence of dma-ranges which is valid for PCI master. > 3) not handling multipe inbound windows. > 4) in order to get largest possible dma_mask. this patch also > retuns the largest possible size based on dma-ranges, > > for e.g. > dma-ranges = <0x43000000 0x00 0x00 0x00 0x00 0x80 0x00>; > we should get dev->coherent_dma_mask=0x7fffffffff. > > based on which IOVA allocation space will honour PCI host > bridge limitations. > > the implementation hooks bus specific callbacks for getting > dma-ranges. > > Signed-off-by: Oza Pawandeep <oza.oza@broadcom.com> > Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com> > Cc: Arnd Bergmann <arnd@arndb.de> > Cc: Geert Uytterhoeven <geert+renesas@glider.be> > Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Cc: Robin Murphy <robin.murphy@arm.com> > Cc: Simon Horman <horms+renesas@verge.net.au> > Cc: Wolfram Sang <wsa@the-dreams.de> > Cc: linux-renesas-soc@vger.kernel.org > To: linux-pci@vger.kernel.org > --- > drivers/of/address.c | 220 +++++++++++++++++++++++++++++-------------- > 1 file changed, 150 insertions(+), 70 deletions(-) > > diff --git a/drivers/of/address.c b/drivers/of/address.c > index 55a4eb7786ca..ae2819e148b8 100644 > --- a/drivers/of/address.c > +++ b/drivers/of/address.c > @@ -8,6 +8,7 @@ > #include <linux/logic_pio.h> > #include <linux/module.h> > #include <linux/of_address.h> > +#include <linux/of_pci.h> > #include <linux/pci.h> > #include <linux/pci_regs.h> > #include <linux/sizes.h> > @@ -48,6 +49,8 @@ struct of_bus { > int na, int ns, int pna); > int (*translate)(__be32 *addr, u64 offset, int na); > unsigned int (*get_flags)(const __be32 *addr); > + int (*get_dma_ranges)(struct device_node *np, > + u64 *dma_addr, u64 *paddr, u64 *size); > }; > > /* > @@ -174,6 +177,143 @@ static int of_bus_pci_translate(__be32 *addr, u64 offset, int na) > return of_bus_default_translate(addr + 1, offset, na - 1); > } > > +static int of_bus_pci_get_dma_ranges(struct device_node *np, u64 *dma_addr, > + u64 *paddr, u64 *size) > +{ > + struct device_node *node = of_node_get(np); > + int ret = 0; > + struct resource_entry *window; > + LIST_HEAD(res); > + > + if (!node) > + return -EINVAL; > + > + *size = 0; > + /* > + * PCI dma-ranges is not mandatory property. > + * many devices do no need to have it, since > + * host bridge does not require inbound memory > + * configuration or rather have design limitations. > + * so we look for dma-ranges, if missing we > + * just return the caller full size, and also > + * no dma-ranges suggests that, host bridge allows > + * whatever comes in, so we set dma_addr to 0. > + */ > + ret = of_pci_get_dma_ranges(np, &res); > + if (!ret) { > + resource_list_for_each_entry(window, &res) { The { should appear on a newline and This block should be indented by one more tab. Or the scope of res_dma could be moved and this extra block avoided. > + struct resource *res_dma = window->res; > + > + if (*size < resource_size(res_dma)) { > + *dma_addr = res_dma->start - window->offset; > + *paddr = res_dma->start; > + *size = resource_size(res_dma); > + } > + } > + } > + pci_free_resource_list(&res); > + > + /* > + * return the largest possible size, > + * since PCI master allows everything. > + */ > + if (*size == 0) { > + pr_debug("empty/zero size dma-ranges found for node(%s)\n", > + np->full_name); > + *size = DMA_BIT_MASK(sizeof(dma_addr_t) * 8) - 1; > + *dma_addr = *paddr = 0; > + ret = 0; > + } > + > + pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", > + *dma_addr, *paddr, *size); > + > + of_node_put(node); > + > + return ret; > +} > + > +static int get_dma_ranges(struct device_node *np, u64 *dma_addr, > + u64 *paddr, u64 *size) > +{ > + struct device_node *node = of_node_get(np); > + const __be32 *ranges = NULL; > + int len, naddr, nsize, pna; > + int ret = 0; > + u64 dmaaddr; > + > + if (!node) > + return -EINVAL; > + > + while (1) { > + naddr = of_n_addr_cells(node); > + nsize = of_n_size_cells(node); > + node = of_get_next_parent(node); > + if (!node) > + break; > + > + ranges = of_get_property(node, "dma-ranges", &len); > + > + /* Ignore empty ranges, they imply no translation required */ > + if (ranges && len > 0) > + break; > + > + /* > + * At least empty ranges has to be defined for parent node if > + * DMA is supported > + */ > + if (!ranges) > + break; > + } > + > + if (!ranges) { > + pr_debug("no dma-ranges found for node(%s)\n", np->full_name); > + ret = -ENODEV; > + goto out; > + } > + > + len /= sizeof(u32); > + > + pna = of_n_addr_cells(node); > + > + /* dma-ranges format: > + * DMA addr : naddr cells > + * CPU addr : pna cells > + * size : nsize cells > + */ > + dmaaddr = of_read_number(ranges, naddr); > + *paddr = of_translate_dma_address(np, ranges); > + if (*paddr == OF_BAD_ADDR) { > + pr_err("translation of DMA address(%pad) to CPU address failed node(%s)\n", > + dma_addr, np->full_name); > + ret = -EINVAL; > + goto out; > + } > + *dma_addr = dmaaddr; > + > + *size = of_read_number(ranges + naddr + pna, nsize); > + > + pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", > + *dma_addr, *paddr, *size); > + > +out: > + of_node_put(node); > + > + return ret; > +} > + > +static int of_bus_isa_get_dma_ranges(struct device_node *np, u64 *dma_addr, > + u64 *paddr, u64 *size) > +{ > + return get_dma_ranges(np, dma_addr, paddr, size); > +} > + > +static int of_bus_default_get_dma_ranges(struct device_node *np, u64 *dma_addr, > + u64 *paddr, u64 *size) > +{ > + return get_dma_ranges(np, dma_addr, paddr, size); > +} > + > const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size, > unsigned int *flags) > { > @@ -438,6 +578,7 @@ static struct of_bus of_busses[] = { > .map = of_bus_pci_map, > .translate = of_bus_pci_translate, > .get_flags = of_bus_pci_get_flags, > + .get_dma_ranges = of_bus_pci_get_dma_ranges, > }, > #endif /* CONFIG_PCI */ > /* ISA */ > @@ -449,6 +590,7 @@ static struct of_bus of_busses[] = { > .map = of_bus_isa_map, > .translate = of_bus_isa_translate, > .get_flags = of_bus_isa_get_flags, > + .get_dma_ranges = of_bus_isa_get_dma_ranges, > }, > /* Default */ > { > @@ -459,6 +601,7 @@ static struct of_bus of_busses[] = { > .map = of_bus_default_map, > .translate = of_bus_default_translate, > .get_flags = of_bus_default_get_flags, > + .get_dma_ranges = of_bus_default_get_dma_ranges, > }, > }; > > @@ -917,80 +1060,17 @@ EXPORT_SYMBOL(of_io_request_and_map); > * size : nsize cells > * > * It returns -ENODEV if "dma-ranges" property was not found > - * for this device in DT. > + * for this device in DT, except if PCI device then, dma-ranges > + * can be optional property, and in that case returns size with > + * entire host memory. > */ > int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size) > { > - struct device_node *node = of_node_get(np); > - const __be32 *ranges = NULL; > - int len, naddr, nsize, pna; > - int ret = 0; > - u64 dmaaddr; > - > - if (!node) > - return -EINVAL; > - > - while (1) { > - struct device_node *parent; > - > - naddr = of_n_addr_cells(node); > - nsize = of_n_size_cells(node); > - > - parent = __of_get_dma_parent(node); > - of_node_put(node); > - > - node = parent; > - if (!node) > - break; > - > - ranges = of_get_property(node, "dma-ranges", &len); > - > - /* Ignore empty ranges, they imply no translation required */ > - if (ranges && len > 0) > - break; > - > - /* > - * At least empty ranges has to be defined for parent node if > - * DMA is supported > - */ > - if (!ranges) > - break; > - } > - > - if (!ranges) { > - pr_debug("no dma-ranges found for node(%pOF)\n", np); > - ret = -ENODEV; > - goto out; > - } > - > - len /= sizeof(u32); > - > - pna = of_n_addr_cells(node); > - > - /* dma-ranges format: > - * DMA addr : naddr cells > - * CPU addr : pna cells > - * size : nsize cells > - */ > - dmaaddr = of_read_number(ranges, naddr); > - *paddr = of_translate_dma_address(np, ranges); > - if (*paddr == OF_BAD_ADDR) { > - pr_err("translation of DMA address(%pad) to CPU address failed node(%pOF)\n", > - dma_addr, np); > - ret = -EINVAL; > - goto out; > - } > - *dma_addr = dmaaddr; > - > - *size = of_read_number(ranges + naddr + pna, nsize); > - > - pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", > - *dma_addr, *paddr, *size); > - > -out: > - of_node_put(node); > + struct of_bus *bus; > > - return ret; > + /* get bus specific dma-ranges. */ > + bus = of_match_bus(np); > + return bus->get_dma_ranges(np, dma_addr, paddr, size); > } > EXPORT_SYMBOL_GPL(of_dma_get_range); > > -- > 2.20.1 >
On Fri, Aug 09, 2019 at 07:34:49PM +0200, marek.vasut@gmail.com wrote: > From: Oza Pawandeep <oza.oza@broadcom.com> > > current device framework and OF framework integration assumes > dma-ranges in a way where memory-mapped devices define their > dma-ranges. (child-bus-address, parent-bus-address, length). "Memory-mapped" means device memory and registers are mapped into the CPU address space so reads/writes from the CPU can access the device. IIUC, the issue you're solving is for DMA, which is the other direction -- DMA reads/writes from the *device* can access system memory. > of_dma_configure is specifically written to take care of memory > mapped devices. but no implementation exists for pci to take > care of pcie based memory ranges. s/pci/PCI/ There's nothing PCIe-specific here; the same issue could occur with either PCI or PCIe, so just say "PCI". > for e.g. iproc based SOCs and other SOCs(such as rcar) have PCI > world dma-ranges. > dma-ranges = <0x43000000 0x00 0x00 0x00 0x00 0x80 0x00>; > > this patch fixes the following problems of_dma_get_range. > 1) return of wrong size as 0. > 2) not handling absence of dma-ranges which is valid for PCI master. > 3) not handling multipe inbound windows. s/multipe/multiple/ > 4) in order to get largest possible dma_mask. this patch also > retuns the largest possible size based on dma-ranges, > > for e.g. > dma-ranges = <0x43000000 0x00 0x00 0x00 0x00 0x80 0x00>; > we should get dev->coherent_dma_mask=0x7fffffffff. > > based on which IOVA allocation space will honour PCI host > bridge limitations. > > the implementation hooks bus specific callbacks for getting > dma-ranges. > > Signed-off-by: Oza Pawandeep <oza.oza@broadcom.com> > Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com> > Cc: Arnd Bergmann <arnd@arndb.de> > Cc: Geert Uytterhoeven <geert+renesas@glider.be> > Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Cc: Robin Murphy <robin.murphy@arm.com> > Cc: Simon Horman <horms+renesas@verge.net.au> > Cc: Wolfram Sang <wsa@the-dreams.de> > Cc: linux-renesas-soc@vger.kernel.org > To: linux-pci@vger.kernel.org > --- > drivers/of/address.c | 220 +++++++++++++++++++++++++++++-------------- > 1 file changed, 150 insertions(+), 70 deletions(-) > > diff --git a/drivers/of/address.c b/drivers/of/address.c > index 55a4eb7786ca..ae2819e148b8 100644 > --- a/drivers/of/address.c > +++ b/drivers/of/address.c > @@ -8,6 +8,7 @@ > #include <linux/logic_pio.h> > #include <linux/module.h> > #include <linux/of_address.h> > +#include <linux/of_pci.h> > #include <linux/pci.h> > #include <linux/pci_regs.h> > #include <linux/sizes.h> > @@ -48,6 +49,8 @@ struct of_bus { > int na, int ns, int pna); > int (*translate)(__be32 *addr, u64 offset, int na); > unsigned int (*get_flags)(const __be32 *addr); > + int (*get_dma_ranges)(struct device_node *np, > + u64 *dma_addr, u64 *paddr, u64 *size); > }; > > /* > @@ -174,6 +177,143 @@ static int of_bus_pci_translate(__be32 *addr, u64 offset, int na) > return of_bus_default_translate(addr + 1, offset, na - 1); > } > > +static int of_bus_pci_get_dma_ranges(struct device_node *np, u64 *dma_addr, > + u64 *paddr, u64 *size) > +{ > + struct device_node *node = of_node_get(np); > + int ret = 0; > + struct resource_entry *window; > + LIST_HEAD(res); > + > + if (!node) > + return -EINVAL; > + > + *size = 0; > + /* > + * PCI dma-ranges is not mandatory property. > + * many devices do no need to have it, since > + * host bridge does not require inbound memory > + * configuration or rather have design limitations. > + * so we look for dma-ranges, if missing we > + * just return the caller full size, and also > + * no dma-ranges suggests that, host bridge allows > + * whatever comes in, so we set dma_addr to 0. Wrap to fill the usual line length in this file. > + */ > + ret = of_pci_get_dma_ranges(np, &res); > + if (!ret) { > + resource_list_for_each_entry(window, &res) { > + struct resource *res_dma = window->res; > + > + if (*size < resource_size(res_dma)) { > + *dma_addr = res_dma->start - window->offset; > + *paddr = res_dma->start; > + *size = resource_size(res_dma); > + } > + } > + } > + pci_free_resource_list(&res); > + > + /* > + * return the largest possible size, > + * since PCI master allows everything. Wrap. > + */ > + if (*size == 0) { > + pr_debug("empty/zero size dma-ranges found for node(%s)\n", > + np->full_name); > + *size = DMA_BIT_MASK(sizeof(dma_addr_t) * 8) - 1; > + *dma_addr = *paddr = 0; > + ret = 0; > + } > + > + pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", > + *dma_addr, *paddr, *size); > + > + of_node_put(node); > + > + return ret; > +} > + > +static int get_dma_ranges(struct device_node *np, u64 *dma_addr, > + u64 *paddr, u64 *size) > +{ > + struct device_node *node = of_node_get(np); > + const __be32 *ranges = NULL; > + int len, naddr, nsize, pna; > + int ret = 0; > + u64 dmaaddr; > + > + if (!node) > + return -EINVAL; > + > + while (1) { > + naddr = of_n_addr_cells(node); > + nsize = of_n_size_cells(node); > + node = of_get_next_parent(node); > + if (!node) > + break; > + > + ranges = of_get_property(node, "dma-ranges", &len); > + > + /* Ignore empty ranges, they imply no translation required */ > + if (ranges && len > 0) > + break; > + > + /* > + * At least empty ranges has to be defined for parent node if > + * DMA is supported > + */ > + if (!ranges) > + break; > + } > + > + if (!ranges) { > + pr_debug("no dma-ranges found for node(%s)\n", np->full_name); > + ret = -ENODEV; > + goto out; > + } > + > + len /= sizeof(u32); > + > + pna = of_n_addr_cells(node); > + > + /* dma-ranges format: > + * DMA addr : naddr cells > + * CPU addr : pna cells > + * size : nsize cells > + */ > + dmaaddr = of_read_number(ranges, naddr); > + *paddr = of_translate_dma_address(np, ranges); > + if (*paddr == OF_BAD_ADDR) { > + pr_err("translation of DMA address(%pad) to CPU address failed node(%s)\n", > + dma_addr, np->full_name); The old code used %pOF; why the change to %s? > + ret = -EINVAL; > + goto out; > + } > + *dma_addr = dmaaddr; > + > + *size = of_read_number(ranges + naddr + pna, nsize); > + > + pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", > + *dma_addr, *paddr, *size); I'm a little confused about the usage of %pad above and %llx here. Are these printing different things, or could they both be done the same way? (There are other occurrences of %llx earlier, too.) > + > +out: > + of_node_put(node); > + > + return ret; > +} > + > +static int of_bus_isa_get_dma_ranges(struct device_node *np, u64 *dma_addr, > + u64 *paddr, u64 *size) > +{ > + return get_dma_ranges(np, dma_addr, paddr, size); > +} > + > +static int of_bus_default_get_dma_ranges(struct device_node *np, u64 *dma_addr, > + u64 *paddr, u64 *size) > +{ > + return get_dma_ranges(np, dma_addr, paddr, size); > +} > + > const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size, > unsigned int *flags) > { > @@ -438,6 +578,7 @@ static struct of_bus of_busses[] = { > .map = of_bus_pci_map, > .translate = of_bus_pci_translate, > .get_flags = of_bus_pci_get_flags, > + .get_dma_ranges = of_bus_pci_get_dma_ranges, > }, > #endif /* CONFIG_PCI */ > /* ISA */ > @@ -449,6 +590,7 @@ static struct of_bus of_busses[] = { > .map = of_bus_isa_map, > .translate = of_bus_isa_translate, > .get_flags = of_bus_isa_get_flags, > + .get_dma_ranges = of_bus_isa_get_dma_ranges, > }, > /* Default */ > { > @@ -459,6 +601,7 @@ static struct of_bus of_busses[] = { > .map = of_bus_default_map, > .translate = of_bus_default_translate, > .get_flags = of_bus_default_get_flags, > + .get_dma_ranges = of_bus_default_get_dma_ranges, > }, > }; > > @@ -917,80 +1060,17 @@ EXPORT_SYMBOL(of_io_request_and_map); > * size : nsize cells > * > * It returns -ENODEV if "dma-ranges" property was not found > - * for this device in DT. > + * for this device in DT, except if PCI device then, dma-ranges > + * can be optional property, and in that case returns size with > + * entire host memory. > */ > int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size) > { > - struct device_node *node = of_node_get(np); > - const __be32 *ranges = NULL; > - int len, naddr, nsize, pna; > - int ret = 0; > - u64 dmaaddr; > - > - if (!node) > - return -EINVAL; > - > - while (1) { > - struct device_node *parent; > - > - naddr = of_n_addr_cells(node); > - nsize = of_n_size_cells(node); > - > - parent = __of_get_dma_parent(node); > - of_node_put(node); > - > - node = parent; > - if (!node) > - break; > - > - ranges = of_get_property(node, "dma-ranges", &len); > - > - /* Ignore empty ranges, they imply no translation required */ > - if (ranges && len > 0) > - break; > - > - /* > - * At least empty ranges has to be defined for parent node if > - * DMA is supported > - */ > - if (!ranges) > - break; > - } > - > - if (!ranges) { > - pr_debug("no dma-ranges found for node(%pOF)\n", np); > - ret = -ENODEV; > - goto out; > - } > - > - len /= sizeof(u32); > - > - pna = of_n_addr_cells(node); > - > - /* dma-ranges format: > - * DMA addr : naddr cells > - * CPU addr : pna cells > - * size : nsize cells > - */ > - dmaaddr = of_read_number(ranges, naddr); > - *paddr = of_translate_dma_address(np, ranges); > - if (*paddr == OF_BAD_ADDR) { > - pr_err("translation of DMA address(%pad) to CPU address failed node(%pOF)\n", > - dma_addr, np); > - ret = -EINVAL; > - goto out; > - } > - *dma_addr = dmaaddr; > - > - *size = of_read_number(ranges + naddr + pna, nsize); > - > - pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", > - *dma_addr, *paddr, *size); > - > -out: > - of_node_put(node); > + struct of_bus *bus; > > - return ret; > + /* get bus specific dma-ranges. */ > + bus = of_match_bus(np); > + return bus->get_dma_ranges(np, dma_addr, paddr, size); > } > EXPORT_SYMBOL_GPL(of_dma_get_range); > > -- > 2.20.1 >
diff --git a/drivers/of/address.c b/drivers/of/address.c index 55a4eb7786ca..ae2819e148b8 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -8,6 +8,7 @@ #include <linux/logic_pio.h> #include <linux/module.h> #include <linux/of_address.h> +#include <linux/of_pci.h> #include <linux/pci.h> #include <linux/pci_regs.h> #include <linux/sizes.h> @@ -48,6 +49,8 @@ struct of_bus { int na, int ns, int pna); int (*translate)(__be32 *addr, u64 offset, int na); unsigned int (*get_flags)(const __be32 *addr); + int (*get_dma_ranges)(struct device_node *np, + u64 *dma_addr, u64 *paddr, u64 *size); }; /* @@ -174,6 +177,143 @@ static int of_bus_pci_translate(__be32 *addr, u64 offset, int na) return of_bus_default_translate(addr + 1, offset, na - 1); } +static int of_bus_pci_get_dma_ranges(struct device_node *np, u64 *dma_addr, + u64 *paddr, u64 *size) +{ + struct device_node *node = of_node_get(np); + int ret = 0; + struct resource_entry *window; + LIST_HEAD(res); + + if (!node) + return -EINVAL; + + *size = 0; + /* + * PCI dma-ranges is not mandatory property. + * many devices do no need to have it, since + * host bridge does not require inbound memory + * configuration or rather have design limitations. + * so we look for dma-ranges, if missing we + * just return the caller full size, and also + * no dma-ranges suggests that, host bridge allows + * whatever comes in, so we set dma_addr to 0. + */ + ret = of_pci_get_dma_ranges(np, &res); + if (!ret) { + resource_list_for_each_entry(window, &res) { + struct resource *res_dma = window->res; + + if (*size < resource_size(res_dma)) { + *dma_addr = res_dma->start - window->offset; + *paddr = res_dma->start; + *size = resource_size(res_dma); + } + } + } + pci_free_resource_list(&res); + + /* + * return the largest possible size, + * since PCI master allows everything. + */ + if (*size == 0) { + pr_debug("empty/zero size dma-ranges found for node(%s)\n", + np->full_name); + *size = DMA_BIT_MASK(sizeof(dma_addr_t) * 8) - 1; + *dma_addr = *paddr = 0; + ret = 0; + } + + pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", + *dma_addr, *paddr, *size); + + of_node_put(node); + + return ret; +} + +static int get_dma_ranges(struct device_node *np, u64 *dma_addr, + u64 *paddr, u64 *size) +{ + struct device_node *node = of_node_get(np); + const __be32 *ranges = NULL; + int len, naddr, nsize, pna; + int ret = 0; + u64 dmaaddr; + + if (!node) + return -EINVAL; + + while (1) { + naddr = of_n_addr_cells(node); + nsize = of_n_size_cells(node); + node = of_get_next_parent(node); + if (!node) + break; + + ranges = of_get_property(node, "dma-ranges", &len); + + /* Ignore empty ranges, they imply no translation required */ + if (ranges && len > 0) + break; + + /* + * At least empty ranges has to be defined for parent node if + * DMA is supported + */ + if (!ranges) + break; + } + + if (!ranges) { + pr_debug("no dma-ranges found for node(%s)\n", np->full_name); + ret = -ENODEV; + goto out; + } + + len /= sizeof(u32); + + pna = of_n_addr_cells(node); + + /* dma-ranges format: + * DMA addr : naddr cells + * CPU addr : pna cells + * size : nsize cells + */ + dmaaddr = of_read_number(ranges, naddr); + *paddr = of_translate_dma_address(np, ranges); + if (*paddr == OF_BAD_ADDR) { + pr_err("translation of DMA address(%pad) to CPU address failed node(%s)\n", + dma_addr, np->full_name); + ret = -EINVAL; + goto out; + } + *dma_addr = dmaaddr; + + *size = of_read_number(ranges + naddr + pna, nsize); + + pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", + *dma_addr, *paddr, *size); + +out: + of_node_put(node); + + return ret; +} + +static int of_bus_isa_get_dma_ranges(struct device_node *np, u64 *dma_addr, + u64 *paddr, u64 *size) +{ + return get_dma_ranges(np, dma_addr, paddr, size); +} + +static int of_bus_default_get_dma_ranges(struct device_node *np, u64 *dma_addr, + u64 *paddr, u64 *size) +{ + return get_dma_ranges(np, dma_addr, paddr, size); +} + const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size, unsigned int *flags) { @@ -438,6 +578,7 @@ static struct of_bus of_busses[] = { .map = of_bus_pci_map, .translate = of_bus_pci_translate, .get_flags = of_bus_pci_get_flags, + .get_dma_ranges = of_bus_pci_get_dma_ranges, }, #endif /* CONFIG_PCI */ /* ISA */ @@ -449,6 +590,7 @@ static struct of_bus of_busses[] = { .map = of_bus_isa_map, .translate = of_bus_isa_translate, .get_flags = of_bus_isa_get_flags, + .get_dma_ranges = of_bus_isa_get_dma_ranges, }, /* Default */ { @@ -459,6 +601,7 @@ static struct of_bus of_busses[] = { .map = of_bus_default_map, .translate = of_bus_default_translate, .get_flags = of_bus_default_get_flags, + .get_dma_ranges = of_bus_default_get_dma_ranges, }, }; @@ -917,80 +1060,17 @@ EXPORT_SYMBOL(of_io_request_and_map); * size : nsize cells * * It returns -ENODEV if "dma-ranges" property was not found - * for this device in DT. + * for this device in DT, except if PCI device then, dma-ranges + * can be optional property, and in that case returns size with + * entire host memory. */ int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size) { - struct device_node *node = of_node_get(np); - const __be32 *ranges = NULL; - int len, naddr, nsize, pna; - int ret = 0; - u64 dmaaddr; - - if (!node) - return -EINVAL; - - while (1) { - struct device_node *parent; - - naddr = of_n_addr_cells(node); - nsize = of_n_size_cells(node); - - parent = __of_get_dma_parent(node); - of_node_put(node); - - node = parent; - if (!node) - break; - - ranges = of_get_property(node, "dma-ranges", &len); - - /* Ignore empty ranges, they imply no translation required */ - if (ranges && len > 0) - break; - - /* - * At least empty ranges has to be defined for parent node if - * DMA is supported - */ - if (!ranges) - break; - } - - if (!ranges) { - pr_debug("no dma-ranges found for node(%pOF)\n", np); - ret = -ENODEV; - goto out; - } - - len /= sizeof(u32); - - pna = of_n_addr_cells(node); - - /* dma-ranges format: - * DMA addr : naddr cells - * CPU addr : pna cells - * size : nsize cells - */ - dmaaddr = of_read_number(ranges, naddr); - *paddr = of_translate_dma_address(np, ranges); - if (*paddr == OF_BAD_ADDR) { - pr_err("translation of DMA address(%pad) to CPU address failed node(%pOF)\n", - dma_addr, np); - ret = -EINVAL; - goto out; - } - *dma_addr = dmaaddr; - - *size = of_read_number(ranges + naddr + pna, nsize); - - pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", - *dma_addr, *paddr, *size); - -out: - of_node_put(node); + struct of_bus *bus; - return ret; + /* get bus specific dma-ranges. */ + bus = of_match_bus(np); + return bus->get_dma_ranges(np, dma_addr, paddr, size); } EXPORT_SYMBOL_GPL(of_dma_get_range);