Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753229AbcKJG0I (ORCPT ); Thu, 10 Nov 2016 01:26:08 -0500 Received: from szxga02-in.huawei.com ([119.145.14.65]:30879 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751400AbcKJG0G (ORCPT ); Thu, 10 Nov 2016 01:26:06 -0500 Subject: Re: [PATCH V5 2/3] ARM64 LPC: Add missing range exception for special ISA To: "liviu.dudau@arm.com" , Gabriele Paoloni References: <1478576829-112707-1-git-send-email-yuanzhichang@hisilicon.com> <1478576829-112707-3-git-send-email-yuanzhichang@hisilicon.com> <20161109113955.GD10219@e106497-lin.cambridge.arm.com> <20161109165044.GE10219@e106497-lin.cambridge.arm.com> 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 , "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 , "zhichang.yuan02@gmail.com" , "kantyzc@163.com" , "xuwei (O)" From: "zhichang.yuan" Message-ID: <58241286.1070107@hisilicon.com> Date: Thu, 10 Nov 2016 14:24:06 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <20161109165044.GE10219@e106497-lin.cambridge.arm.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.57.79.81] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9358 Lines: 311 Hi,Liviu, Thanks for your comments! On 2016/11/10 0:50, liviu.dudau@arm.com wrote: > On Wed, Nov 09, 2016 at 04:16:17PM +0000, Gabriele Paoloni wrote: >> Hi Liviu >> >> Thanks for reviewing >> > > [removed some irrelevant part of discussion, avoid crazy formatting] > >>>> +/** >>>> + * 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 ? >> >> Nope... if (taddr < arm64_extio_ops->start || taddr > arm64_extio_ops->end) >> then taddr is outside the range [start; end] and will return 0; otherwise >> it will return 1... > > Oops, sorry, did not pay attention to the returned value. The check is > correct as it is, no need to change then. > >> >>> >>>> + 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. >> >> Yes we'll move to 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'/ >> >> Thanks for spotting this >> >>> >>>> + 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, >> >> I think you're wrong here as in pci_address_to_pio we have: >> + resource_size_t offset = PCIBIOS_MIN_IO; >> >> This should be enough to guarantee that the PIOs start at >> PCIBIOS_MIN_IO...right? > > I don't think you can guarantee that the pio value that gets passed into > pci_pio_to_address() always comes from a previously returned value by > pci_address_to_pio(). Maybe you can add a check in pci_pio_to_address() > > if (pio < PCIBIOS_MIN_IO) > return address; > > to avoid adding more checks in the list_for_each_entry() loop. > I will register some ranges to the list and test it later. But from my understanding, pci_pio_to_address() should can return the right original physical address. According to the algorithm, the output PIO ranges are consecutiveļ¼Œ just like this: input pio of pci_pio_to_address() | V |----------------|--------------------------|------|-----------| ^ | allocated_size is here The change of this patch just make the start PIO from ZERO to PCIBIOS_MIN_IO. in pci_pio_to_address(), for one input pio which fall into any PIO segment, the return address will be: address = range->start + pio - allocated_size; Since allocated_size is the total range size of all IO ranges before the one where pio belong, then (pio - allocated_size) is the offset to the range start, So.... Thanks! Zhichang > Best regards, > Liviu > >> >> >>> 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 >