Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933500AbcKILkE (ORCPT ); Wed, 9 Nov 2016 06:40:04 -0500 Received: from foss.arm.com ([217.140.101.70]:51480 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932638AbcKILj6 (ORCPT ); Wed, 9 Nov 2016 06:39:58 -0500 Date: Wed, 9 Nov 2016 11:39:55 +0000 From: liviu.dudau@arm.com To: "zhichang.yuan" Cc: catalin.marinas@arm.com, will.deacon@arm.com, robh+dt@kernel.org, bhelgaas@google.com, mark.rutland@arm.com, olof@lixom.net, arnd@arndb.de, linux-arm-kernel@lists.infradead.org, lorenzo.pieralisi@arm.com, linux-kernel@vger.kernel.org, linuxarm@huawei.com, devicetree@vger.kernel.org, linux-pci@vger.kernel.org, linux-serial@vger.kernel.org, minyard@acm.org, benh@kernel.crashing.org, zourongrong@gmail.com, john.garry@huawei.com, gabriele.paoloni@huawei.com, zhichang.yuan02@gmail.com, kantyzc@163.com, xuwei5@hisilicon.com Subject: Re: [PATCH V5 2/3] ARM64 LPC: Add missing range exception for special ISA Message-ID: <20161109113955.GD10219@e106497-lin.cambridge.arm.com> References: <1478576829-112707-1-git-send-email-yuanzhichang@hisilicon.com> <1478576829-112707-3-git-send-email-yuanzhichang@hisilicon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1478576829-112707-3-git-send-email-yuanzhichang@hisilicon.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 11710 Lines: 334 On Tue, Nov 08, 2016 at 11:47:08AM +0800, zhichang.yuan wrote: > This patch solves two issues: > 1) parse and get the right I/O range from DTS node whose parent does not > define the corresponding ranges property; > > There are some special ISA/LPC devices that work on a specific I/O range where > it is not correct to specify a ranges property in DTS parent node as cpu > addresses translated from DTS node are only for memory space on some > architectures, such as Arm64. Without the parent 'ranges' property, current > of_translate_address() return an error. > Here we add a fixup function, of_get_isa_indirect_io(). During the OF address > translation, this fixup will be called to check the 'reg' address to be > translating is for those sepcial ISA/LPC devices and get the I/O range > directly from the 'reg' property. > > 2) eliminate the I/O range conflict risk with PCI/PCIE leagecy I/O device; > > The current __of_address_to_resource() always translates the I/O range to PIO. > But this processing is not suitable for our ISA/LPC devices whose I/O range is > not cpu address(Arnd had stressed this in his comments on V2,V3 patch-set). > Here, we bypass the mapping between cpu address and PIO for the special > ISA/LPC devices. But to drive these ISA/LPC devices, a I/O port address below > PCIBIOS_MIN_IO is needed by in*/out*(). Which means there is conflict risk > between I/O range of [0, PCIBIOS_MIN_IO) and PCI/PCIE legacy I/O range of [0, > IO_SPACE_LIMIT). > To avoid the I/O conflict, this patch reserve the I/O range below > PCIBIOS_MIN_IO. > > Signed-off-by: zhichang.yuan > Signed-off-by: Gabriele Paoloni > --- > .../arm/hisilicon/hisilicon-low-pin-count.txt | 31 ++++++++++++ > arch/arm64/include/asm/io.h | 6 +++ > arch/arm64/kernel/extio.c | 25 ++++++++++ > drivers/of/address.c | 56 +++++++++++++++++++++- > drivers/pci/pci.c | 6 +-- > include/linux/of_address.h | 17 +++++++ > include/linux/pci.h | 8 ++++ > 7 files changed, 145 insertions(+), 4 deletions(-) > create mode 100644 Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt > > diff --git a/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt b/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt > new file mode 100644 > index 0000000..13c8ddd > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt > @@ -0,0 +1,31 @@ > +Hisilicon Hip06 low-pin-count device > + Usually LPC controller is part of PCI host bridge, so the legacy ISA ports > + locate on LPC bus can be accessed direclty. But some SoCs have independent > + LPC controller, and access the legacy ports by triggering LPC I/O cycles. > + Hisilicon Hip06 implements this LPC device. > + > +Required properties: > +- compatible: should be "hisilicon,low-pin-count" > +- #address-cells: must be 2 which stick to the ISA/EISA binding doc. > +- #size-cells: must be 1 which stick to the ISA/EISA binding doc. > +- reg: base memory range where the register set of this device is mapped. > + > +Note: > + The node name before '@' must be "isa" to represent the binding stick to the > + ISA/EISA binding specification. > + > +Example: > + > +isa@a01b0000 { > + compatible = "hisilicom,low-pin-count"; > + #address-cells = <2>; > + #size-cells = <1>; > + reg = <0x0 0xa01b0000 0x0 0x1000>; > + > + ipmi0: bt@e4 { > + compatible = "ipmi-bt"; > + device_type = "ipmi"; > + reg = <0x01 0xe4 0x04>; > + status = "disabled"; > + }; > +}; This documentation file needs to be part of the next patch. It has nothing to do with what you are trying to fix here. > diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h > index 136735d..c26b7cc 100644 > --- a/arch/arm64/include/asm/io.h > +++ b/arch/arm64/include/asm/io.h > @@ -175,6 +175,12 @@ static inline u64 __raw_readq(const volatile void __iomem *addr) > #define outsl outsl > > DECLARE_EXTIO(l, u32) > + > +#define indirect_io_enabled indirect_io_enabled > +extern bool indirect_io_enabled(void); > + > +#define addr_is_indirect_io addr_is_indirect_io > +extern int addr_is_indirect_io(u64 taddr); > #endif > > > diff --git a/arch/arm64/kernel/extio.c b/arch/arm64/kernel/extio.c > index 647b3fa..3d45fa8 100644 > --- a/arch/arm64/kernel/extio.c > +++ b/arch/arm64/kernel/extio.c > @@ -19,6 +19,31 @@ > > struct extio_ops *arm64_extio_ops; > > +/** > + * indirect_io_enabled - check whether indirectIO is enabled. > + * arm64_extio_ops will be set only when indirectIO mechanism had been > + * initialized. > + * > + * Returns true when indirectIO is enabled. > + */ > +bool indirect_io_enabled(void) > +{ > + return arm64_extio_ops ? true : false; > +} > + > +/** > + * addr_is_indirect_io - check whether the input taddr is for indirectIO. > + * @taddr: the io address to be checked. > + * > + * Returns 1 when taddr is in the range; otherwise return 0. > + */ > +int addr_is_indirect_io(u64 taddr) > +{ > + if (arm64_extio_ops->start > taddr || arm64_extio_ops->end < taddr) start >= taddr ? > + return 0; > + > + return 1; > +} > > BUILD_EXTIO(b, u8) > > diff --git a/drivers/of/address.c b/drivers/of/address.c > index 02b2903..cc2a05d 100644 > --- a/drivers/of/address.c > +++ b/drivers/of/address.c > @@ -479,6 +479,50 @@ static int of_empty_ranges_quirk(struct device_node *np) > return false; > } > > + > +/* > + * of_isa_indirect_io - get the IO address from some isa reg property value. > + * For some isa/lpc devices, no ranges property in ancestor node. > + * The device addresses are described directly in their regs property. > + * This fixup function will be called to get the IO address of isa/lpc > + * devices when the normal of_translation failed. > + * > + * @parent: points to the parent dts node; > + * @bus: points to the of_bus which can be used to parse address; > + * @addr: the address from reg property; > + * @na: the address cell counter of @addr; > + * @presult: store the address paresed from @addr; > + * > + * return 1 when successfully get the I/O address; > + * 0 will return for some failures. Bah, you are returning a signed int, why 0 for failure? Return a negative value with error codes. Otherwise change the return value into a bool. > + */ > +static int of_get_isa_indirect_io(struct device_node *parent, > + struct of_bus *bus, __be32 *addr, > + int na, u64 *presult) > +{ > + unsigned int flags; > + unsigned int rlen; > + > + /* whether support indirectIO */ > + if (!indirect_io_enabled()) > + return 0; > + > + if (!of_bus_isa_match(parent)) > + return 0; > + > + flags = bus->get_flags(addr); > + if (!(flags & IORESOURCE_IO)) > + return 0; > + > + /* there is ranges property, apply the normal translation directly. */ s/there is ranges/if we have a 'ranges'/ > + if (of_get_property(parent, "ranges", &rlen)) > + return 0; > + > + *presult = of_read_number(addr + 1, na - 1); > + /* this fixup is only valid for specific I/O range. */ > + return addr_is_indirect_io(*presult); > +} > + > static int of_translate_one(struct device_node *parent, struct of_bus *bus, > struct of_bus *pbus, __be32 *addr, > int na, int ns, int pna, const char *rprop) > @@ -595,6 +639,15 @@ static u64 __of_translate_address(struct device_node *dev, > result = of_read_number(addr, na); > break; > } > + /* > + * For indirectIO device which has no ranges property, get > + * the address from reg directly. > + */ > + if (of_get_isa_indirect_io(dev, bus, addr, na, &result)) { > + pr_debug("isa indirectIO matched(%s)..addr = 0x%llx\n", > + of_node_full_name(dev), result); > + break; > + } > > /* Get new parent bus and counts */ > pbus = of_match_bus(parent); > @@ -688,8 +741,9 @@ static int __of_address_to_resource(struct device_node *dev, > if (taddr == OF_BAD_ADDR) > return -EINVAL; > memset(r, 0, sizeof(struct resource)); > - if (flags & IORESOURCE_IO) { > + if (flags & IORESOURCE_IO && taddr >= PCIBIOS_MIN_IO) { > unsigned long port; > + > port = pci_address_to_pio(taddr); > if (port == (unsigned long)-1) > return -EINVAL; > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index ba34907..1a08511 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -3263,7 +3263,7 @@ int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size) > > #ifdef PCI_IOBASE > struct io_range *range; > - resource_size_t allocated_size = 0; > + resource_size_t allocated_size = PCIBIOS_MIN_IO; > > /* check if the range hasn't been previously recorded */ > spin_lock(&io_range_lock); > @@ -3312,7 +3312,7 @@ phys_addr_t pci_pio_to_address(unsigned long pio) > > #ifdef PCI_IOBASE > struct io_range *range; > - resource_size_t allocated_size = 0; > + resource_size_t allocated_size = PCIBIOS_MIN_IO; Have you checked that pci_pio_to_address still returns valid values after this? I know that you are trying to take into account PCIBIOS_MIN_IO limit when allocating reserving the IO ranges, but the values added in the io_range_list are still starting from zero, no from PCIBIOS_MIN_IO, so the calculation of the address in this function could return negative values casted to pci_addr_t. Maybe you want to adjust the range->start value in pci_register_io_range() as well to have it offset by PCIBIOS_MIN_IO as well. Best regards, Liviu > > if (pio > IO_SPACE_LIMIT) > return address; > @@ -3335,7 +3335,7 @@ unsigned long __weak pci_address_to_pio(phys_addr_t address) > { > #ifdef PCI_IOBASE > struct io_range *res; > - resource_size_t offset = 0; > + resource_size_t offset = PCIBIOS_MIN_IO; > unsigned long addr = -1; > > spin_lock(&io_range_lock); > diff --git a/include/linux/of_address.h b/include/linux/of_address.h > index 3786473..deec469 100644 > --- a/include/linux/of_address.h > +++ b/include/linux/of_address.h > @@ -24,6 +24,23 @@ struct of_pci_range { > #define for_each_of_pci_range(parser, range) \ > for (; of_pci_range_parser_one(parser, range);) > > + > +#ifndef indirect_io_enabled > +#define indirect_io_enabled indirect_io_enabled > +static inline bool indirect_io_enabled(void) > +{ > + return false; > +} > +#endif > + > +#ifndef addr_is_indirect_io > +#define addr_is_indirect_io addr_is_indirect_io > +static inline int addr_is_indirect_io(u64 taddr) > +{ > + return 0; > +} > +#endif > + > /* Translate a DMA address from device space to CPU space */ > extern u64 of_translate_dma_address(struct device_node *dev, > const __be32 *in_addr); > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 0e49f70..7f6bbb6 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -2130,4 +2130,12 @@ static inline bool pci_ari_enabled(struct pci_bus *bus) > /* provide the legacy pci_dma_* API */ > #include > > +/* > + * define this macro here to refrain from compilation error for some > + * platforms. Please keep this macro at the end of this header file. > + */ > +#ifndef PCIBIOS_MIN_IO > +#define PCIBIOS_MIN_IO 0 > +#endif > + > #endif /* LINUX_PCI_H */ > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯