| Message ID | 1397917972-6293-3-git-send-email-santosh.shilimkar@ti.com |
|---|---|
| State | New |
| Headers | show |
On Sat, Apr 19, 2014 at 9:32 AM, Santosh Shilimkar <santosh.shilimkar@ti.com> wrote: > From: Grygorii Strashko <grygorii.strashko@ti.com> > > The of_dma_get_range() allows to find "dma-range" property for > the specified device and parse it. > dma-ranges format: > DMA addr (dma_addr) : naddr cells > CPU addr (phys_addr_t) : pna cells > size : nsize cells > > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Cc: Russell King <linux@arm.linux.org.uk> > Cc: Arnd Bergmann <arnd@arndb.de> > Cc: Olof Johansson <olof@lixom.net> > Cc: Grant Likely <grant.likely@linaro.org> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Linus Walleij <linus.walleij@linaro.org> > Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> > Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> > --- > drivers/of/platform.c | 85 +++++++++++++++++++++++++++++++++++++++++++ > include/linux/of_platform.h | 8 ++++ This belongs in drivers/of/address.c and of_address.h. > 2 files changed, 93 insertions(+) > > diff --git a/drivers/of/platform.c b/drivers/of/platform.c > index 404d1da..2265a55 100644 > --- a/drivers/of/platform.c > +++ b/drivers/of/platform.c > @@ -485,4 +485,89 @@ int of_platform_populate(struct device_node *root, > return rc; > } > EXPORT_SYMBOL_GPL(of_platform_populate); > + > +/** > + * of_dma_get_range - Get DMA range info > + * @np: device node to get DMA range info > + * @dma_addr: pointer to store initial DMA address of DMA range > + * @paddr: pointer to store initial CPU address of DMA range > + * @size: pointer to store size of DMA range > + * > + * Look in bottom up direction for the first "dma-range" property dma-ranges > + * and parse it. > + * dma-ranges format: > + * DMA addr (dma_addr) : naddr cells > + * CPU addr (phys_addr_t) : pna cells > + * size : nsize cells > + * > + * It returns -ENODEV if "dma-ranges" property was not found > + * for this device in DT. > + */ > +extern int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, drop extern. > + phys_addr_t *paddr, phys_addr_t *size) > +{ > + struct device_node *node = np; > + const u32 *ranges = NULL; __be32 > + int len, naddr, nsize, pna; > + int ret = 0; > + > + 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; You need an of_node_put here if you are getting the next parent. > + } > + > + if (!ranges) { > + pr_debug("%s: no dma-ranges found for node(%s)\n", > + __func__, 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 > + */ > + *dma_addr = of_read_number(ranges, naddr); You should set this after the following call succeeds. > + *paddr = of_translate_dma_address(np, ranges); This is going to search for dma-ranges again, but you have already done that. Is there a case that just reading the CPU addr will not work? I suppose we could have more than one level of translation. It also seems a bit abusive that the DMA address is the ranges property. I don't really have a better suggestion though. > + if (*paddr == OF_BAD_ADDR) { As I mentioned, this is potentially a size mismatch. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 04/19/2014 09:32 AM, Santosh Shilimkar wrote: > From: Grygorii Strashko <grygorii.strashko@ti.com> [..] > + * Look in bottom up direction for the first "dma-range" property > + * and parse it. > + * dma-ranges format: > + * DMA addr (dma_addr) : naddr cells > + * CPU addr (phys_addr_t) : pna cells > + * size : nsize cells > + * > + * It returns -ENODEV if "dma-ranges" property was not found > + * for this device in DT. > + */ > +extern int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, > + phys_addr_t *paddr, phys_addr_t *size) > +{ > + struct device_node *node = np; > + const u32 *ranges = NULL; > + int len, naddr, nsize, pna; > + int ret = 0; > + > + 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("%s: no dma-ranges found for node(%s)\n", > + __func__, 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 > + */ > + *dma_addr = of_read_number(ranges, naddr); > + *paddr = of_translate_dma_address(np, ranges); I am probably missing something but I'm wondering the need for a translate step here instead of doing something like: *paddr = of_read_number(ranges + naddr, pna); Perhaps there is a need to do a translate step of the DMA Address in dma-ranges all the way to the parent, which can be different from the CPU Address (second address in dma-ranges). in which case the format of dma-ranges after parsing looks like <DMA-Addr Translate(DMA-Addr) Size> to the caller, and not, <DMA-Addr CPU-Addr Size> But for keystone if something like the following is used, dma-ranges = <0x80000000 0x8 0x00000000 0x80000000>; Then, the above fragment I proposed would return 0x8 0x00000000 which is sufficient? thanks, -Joel > + if (*paddr == OF_BAD_ADDR) { > + pr_err("%s: translation of DMA address(%pad) to CPU address failed node(%s)\n", > + __func__, dma_addr, np->full_name); > + ret = -EINVAL; > + } > + > + *size = of_read_number(ranges + naddr + pna, nsize); > + > + pr_debug("dma_addr(%pad) cpu_addr(%pa) size(%pa)\n", > + dma_addr, paddr, size); > + > +out: > + of_node_put(node); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(of_dma_get_range); > #endif /* CONFIG_OF_ADDRESS */ > diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h > index 05cb4a9..ba7d3dc 100644 > --- a/include/linux/of_platform.h > +++ b/include/linux/of_platform.h > @@ -72,6 +72,8 @@ extern int of_platform_populate(struct device_node *root, > const struct of_device_id *matches, > const struct of_dev_auxdata *lookup, > struct device *parent); > +extern int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, > + phys_addr_t *paddr, phys_addr_t *size); > #else > static inline int of_platform_populate(struct device_node *root, > const struct of_device_id *matches, > @@ -80,6 +82,12 @@ static inline int of_platform_populate(struct device_node *root, > { > return -ENODEV; > } > + > +static inline int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, > + phys_addr_t *paddr, phys_addr_t *size) > +{ > + return -ENODEV; > +} > #endif > > #endif /* _LINUX_OF_PLATFORM_H */ > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Rob, On 04/21/2014 06:29 PM, Rob Herring wrote: > On Sat, Apr 19, 2014 at 9:32 AM, Santosh Shilimkar > <santosh.shilimkar@ti.com> wrote: >> From: Grygorii Strashko <grygorii.strashko@ti.com> >> >> The of_dma_get_range() allows to find "dma-range" property for >> the specified device and parse it. >> dma-ranges format: >> DMA addr (dma_addr) : naddr cells >> CPU addr (phys_addr_t) : pna cells >> size : nsize cells >> >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> >> Cc: Russell King <linux@arm.linux.org.uk> >> Cc: Arnd Bergmann <arnd@arndb.de> >> Cc: Olof Johansson <olof@lixom.net> >> Cc: Grant Likely <grant.likely@linaro.org> >> Cc: Rob Herring <robh+dt@kernel.org> >> Cc: Catalin Marinas <catalin.marinas@arm.com> >> Cc: Linus Walleij <linus.walleij@linaro.org> >> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> >> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> >> --- >> drivers/of/platform.c | 85 +++++++++++++++++++++++++++++++++++++++++++ >> include/linux/of_platform.h | 8 ++++ > > This belongs in drivers/of/address.c and of_address.h. > >> 2 files changed, 93 insertions(+) >> >> diff --git a/drivers/of/platform.c b/drivers/of/platform.c >> index 404d1da..2265a55 100644 >> --- a/drivers/of/platform.c >> +++ b/drivers/of/platform.c >> @@ -485,4 +485,89 @@ int of_platform_populate(struct device_node *root, >> return rc; >> } >> EXPORT_SYMBOL_GPL(of_platform_populate); >> + >> +/** >> + * of_dma_get_range - Get DMA range info >> + * @np: device node to get DMA range info >> + * @dma_addr: pointer to store initial DMA address of DMA range >> + * @paddr: pointer to store initial CPU address of DMA range >> + * @size: pointer to store size of DMA range >> + * >> + * Look in bottom up direction for the first "dma-range" property > > dma-ranges > >> + * and parse it. >> + * dma-ranges format: >> + * DMA addr (dma_addr) : naddr cells >> + * CPU addr (phys_addr_t) : pna cells >> + * size : nsize cells >> + * >> + * It returns -ENODEV if "dma-ranges" property was not found >> + * for this device in DT. >> + */ >> +extern int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, > > drop extern. > >> + phys_addr_t *paddr, phys_addr_t *size) >> +{ >> + struct device_node *node = np; >> + const u32 *ranges = NULL; > > __be32 > >> + int len, naddr, nsize, pna; >> + int ret = 0; >> + >> + 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; > > You need an of_node_put here if you are getting the next parent. Seems, It's not needed, because of_get_next_parent() does following: parent = of_node_get(node->parent); of_node_put(node); > >> + } >> + >> + if (!ranges) { >> + pr_debug("%s: no dma-ranges found for node(%s)\n", >> + __func__, 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 >> + */ >> + *dma_addr = of_read_number(ranges, naddr); > > You should set this after the following call succeeds. > >> + *paddr = of_translate_dma_address(np, ranges); > > This is going to search for dma-ranges again, but you have already > done that. Is there a case that just reading the CPU addr will not > work? I suppose we could have more than one level of translation. It > also seems a bit abusive that the DMA address is the ranges property. > I don't really have a better suggestion though. I think, We need to keep using of_translate_dma_address(), because this code intended to be generic and, as result, there is no guarantee that we will always have one level of translations. > >> + if (*paddr == OF_BAD_ADDR) { > > As I mentioned, this is potentially a size mismatch. Thanks for your review. Regards, Grygorii -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/drivers/of/platform.c b/drivers/of/platform.c index 404d1da..2265a55 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -485,4 +485,89 @@ int of_platform_populate(struct device_node *root, return rc; } EXPORT_SYMBOL_GPL(of_platform_populate); + +/** + * of_dma_get_range - Get DMA range info + * @np: device node to get DMA range info + * @dma_addr: pointer to store initial DMA address of DMA range + * @paddr: pointer to store initial CPU address of DMA range + * @size: pointer to store size of DMA range + * + * Look in bottom up direction for the first "dma-range" property + * and parse it. + * dma-ranges format: + * DMA addr (dma_addr) : naddr cells + * CPU addr (phys_addr_t) : pna cells + * size : nsize cells + * + * It returns -ENODEV if "dma-ranges" property was not found + * for this device in DT. + */ +extern int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, + phys_addr_t *paddr, phys_addr_t *size) +{ + struct device_node *node = np; + const u32 *ranges = NULL; + int len, naddr, nsize, pna; + int ret = 0; + + 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("%s: no dma-ranges found for node(%s)\n", + __func__, 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 + */ + *dma_addr = of_read_number(ranges, naddr); + *paddr = of_translate_dma_address(np, ranges); + if (*paddr == OF_BAD_ADDR) { + pr_err("%s: translation of DMA address(%pad) to CPU address failed node(%s)\n", + __func__, dma_addr, np->full_name); + ret = -EINVAL; + } + + *size = of_read_number(ranges + naddr + pna, nsize); + + pr_debug("dma_addr(%pad) cpu_addr(%pa) size(%pa)\n", + dma_addr, paddr, size); + +out: + of_node_put(node); + + return ret; +} +EXPORT_SYMBOL_GPL(of_dma_get_range); #endif /* CONFIG_OF_ADDRESS */ diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h index 05cb4a9..ba7d3dc 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -72,6 +72,8 @@ extern int of_platform_populate(struct device_node *root, const struct of_device_id *matches, const struct of_dev_auxdata *lookup, struct device *parent); +extern int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, + phys_addr_t *paddr, phys_addr_t *size); #else static inline int of_platform_populate(struct device_node *root, const struct of_device_id *matches, @@ -80,6 +82,12 @@ static inline int of_platform_populate(struct device_node *root, { return -ENODEV; } + +static inline int of_dma_get_range(struct device_node *np, dma_addr_t *dma_addr, + phys_addr_t *paddr, phys_addr_t *size) +{ + return -ENODEV; +} #endif #endif /* _LINUX_OF_PLATFORM_H */