diff mbox series

[4/4] PCI: Enable 10-Bit tag support for PCIe RP devices

Message ID 1617440059-2478-5-git-send-email-liudongdong3@huawei.com (mailing list archive)
State New
Delegated to: Bjorn Helgaas
Headers show
Series PCI: Enable 10-Bit tag support for PCIe devices | expand

Commit Message

Dongdong Liu April 3, 2021, 8:54 a.m. UTC
PCIe spec 5.0r1.0 section 2.2.6.2 implementation note, In configurations
where a Requester with 10-Bit Tag Requester capability needs to target
multiple Completers, one needs to ensure that the Requester sends 10-Bit
Tag Requests only to Completers that have 10-Bit Tag Completer capability.
So we enable 10-Bit Tag Requester for root port only when the devices
under the root port support 10-Bit Tag Completer.

Signed-off-by: Dongdong Liu <liudongdong3@huawei.com>
---
 drivers/pci/pci.h              |  2 +
 drivers/pci/pcie/portdrv_pci.c |  3 ++
 drivers/pci/probe.c            | 86 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 91 insertions(+)

Comments

kernel test robot April 3, 2021, 10:32 a.m. UTC | #1
Hi Dongdong,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on pci/next]
[also build test ERROR on v5.12-rc5 next-20210401]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Dongdong-Liu/PCI-Enable-10-Bit-tag-support-for-PCIe-devices/20210403-171726
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: i386-randconfig-m021-20210403 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/c1497e514c78375b8c9e9e074e5b84c62eaef20f
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Dongdong-Liu/PCI-Enable-10-Bit-tag-support-for-PCIe-devices/20210403-171726
        git checkout c1497e514c78375b8c9e9e074e5b84c62eaef20f
        # save the attached .config to linux build tree
        make W=1 ARCH=i386 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

>> drivers/pci/probe.c:2096:6: error: redefinition of 'pci_configure_rp_10bit_tag'
    2096 | void pci_configure_rp_10bit_tag(struct pci_dev *dev)
         |      ^~~~~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/pci/probe.c:22:
   drivers/pci/pci.h:468:20: note: previous definition of 'pci_configure_rp_10bit_tag' was here
     468 | static inline void pci_configure_rp_10bit_tag(struct pci_dev *dev) {}
         |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~


vim +/pci_configure_rp_10bit_tag +2096 drivers/pci/probe.c

  2095	
> 2096	void pci_configure_rp_10bit_tag(struct pci_dev *dev)
  2097	{
  2098		u8 support = 1;
  2099		u32 cap;
  2100		int ret;
  2101	
  2102		if (!pci_is_pcie(dev))
  2103			return;
  2104	
  2105		if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
  2106			return;
  2107	
  2108		if (dev->subordinate == NULL)
  2109			return;
  2110	
  2111		pci_10bit_tag_comp_support(dev, &support);
  2112		if (!support)
  2113			return;
  2114	
  2115		/*
  2116		 * PCIe spec 5.0r1.0 section 2.2.6.2 implementation note
  2117		 * In configurations where a Requester with 10-Bit Tag Requester capability
  2118		 * needs to target multiple Completers, one needs to ensure that the
  2119		 * Requester sends 10-Bit Tag Requests only to Completers that have 10-Bit
  2120		 * Tag Completer capability. So we enable 10-Bit Tag Requester for root port
  2121		 * only when the devices under the root port support 10-Bit Tag Completer.
  2122		 */
  2123		pci_walk_bus(dev->subordinate, pci_10bit_tag_comp_support, &support);
  2124		if (!support)
  2125			return;
  2126	
  2127		ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
  2128		if (ret)
  2129			return;
  2130	
  2131		if (!(cap & PCI_EXP_DEVCAP2_10BIT_TAG_REQ))
  2132			return;
  2133	
  2134		pci_info(dev, "enabling 10-Bit Tag Requester\n");
  2135		pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
  2136					 PCI_EXP_DEVCTL2_10BIT_TAG_REQ_EN);
  2137	}
  2138	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
kernel test robot April 3, 2021, 12:33 p.m. UTC | #2
Hi Dongdong,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on pci/next]
[also build test ERROR on v5.12-rc5 next-20210401]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Dongdong-Liu/PCI-Enable-10-Bit-tag-support-for-PCIe-devices/20210403-171726
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: x86_64-randconfig-a004-20210403 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 0fe8af94688aa03c01913c2001d6a1a911f42ce6)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # https://github.com/0day-ci/linux/commit/c1497e514c78375b8c9e9e074e5b84c62eaef20f
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Dongdong-Liu/PCI-Enable-10-Bit-tag-support-for-PCIe-devices/20210403-171726
        git checkout c1497e514c78375b8c9e9e074e5b84c62eaef20f
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

>> drivers/pci/probe.c:2096:6: error: redefinition of 'pci_configure_rp_10bit_tag'
   void pci_configure_rp_10bit_tag(struct pci_dev *dev)
        ^
   drivers/pci/pci.h:468:20: note: previous definition is here
   static inline void pci_configure_rp_10bit_tag(struct pci_dev *dev) {}
                      ^
   1 error generated.


vim +/pci_configure_rp_10bit_tag +2096 drivers/pci/probe.c

  2095	
> 2096	void pci_configure_rp_10bit_tag(struct pci_dev *dev)
  2097	{
  2098		u8 support = 1;
  2099		u32 cap;
  2100		int ret;
  2101	
  2102		if (!pci_is_pcie(dev))
  2103			return;
  2104	
  2105		if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
  2106			return;
  2107	
  2108		if (dev->subordinate == NULL)
  2109			return;
  2110	
  2111		pci_10bit_tag_comp_support(dev, &support);
  2112		if (!support)
  2113			return;
  2114	
  2115		/*
  2116		 * PCIe spec 5.0r1.0 section 2.2.6.2 implementation note
  2117		 * In configurations where a Requester with 10-Bit Tag Requester capability
  2118		 * needs to target multiple Completers, one needs to ensure that the
  2119		 * Requester sends 10-Bit Tag Requests only to Completers that have 10-Bit
  2120		 * Tag Completer capability. So we enable 10-Bit Tag Requester for root port
  2121		 * only when the devices under the root port support 10-Bit Tag Completer.
  2122		 */
  2123		pci_walk_bus(dev->subordinate, pci_10bit_tag_comp_support, &support);
  2124		if (!support)
  2125			return;
  2126	
  2127		ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
  2128		if (ret)
  2129			return;
  2130	
  2131		if (!(cap & PCI_EXP_DEVCAP2_10BIT_TAG_REQ))
  2132			return;
  2133	
  2134		pci_info(dev, "enabling 10-Bit Tag Requester\n");
  2135		pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
  2136					 PCI_EXP_DEVCTL2_10BIT_TAG_REQ_EN);
  2137	}
  2138	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Dongdong Liu April 6, 2021, 2:41 a.m. UTC | #3
Thnaks for your report. I made a mistake.
Maybe I need to move these functions implementation
to drivers/pci/pcie/portdrv_pci.c. No need to
define in drivers/pci/pci.h

Thanks,
Dongdong
On 2021/4/3 20:33, kernel test robot wrote:
> Hi Dongdong,
>
> Thank you for the patch! Yet something to improve:
>
> [auto build test ERROR on pci/next]
> [also build test ERROR on v5.12-rc5 next-20210401]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch]
>
> url:    https://github.com/0day-ci/linux/commits/Dongdong-Liu/PCI-Enable-10-Bit-tag-support-for-PCIe-devices/20210403-171726
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
> config: x86_64-randconfig-a004-20210403 (attached as .config)
> compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 0fe8af94688aa03c01913c2001d6a1a911f42ce6)
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install x86_64 cross compiling tool for clang build
>         # apt-get install binutils-x86-64-linux-gnu
>         # https://github.com/0day-ci/linux/commit/c1497e514c78375b8c9e9e074e5b84c62eaef20f
>         git remote add linux-review https://github.com/0day-ci/linux
>         git fetch --no-tags linux-review Dongdong-Liu/PCI-Enable-10-Bit-tag-support-for-PCIe-devices/20210403-171726
>         git checkout c1497e514c78375b8c9e9e074e5b84c62eaef20f
>         # save the attached .config to linux build tree
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
>
> All errors (new ones prefixed by >>):
>
>>> drivers/pci/probe.c:2096:6: error: redefinition of 'pci_configure_rp_10bit_tag'
>    void pci_configure_rp_10bit_tag(struct pci_dev *dev)
>         ^
>    drivers/pci/pci.h:468:20: note: previous definition is here
>    static inline void pci_configure_rp_10bit_tag(struct pci_dev *dev) {}
>                       ^
>    1 error generated.
>
>
> vim +/pci_configure_rp_10bit_tag +2096 drivers/pci/probe.c
>
>   2095	
>> 2096	void pci_configure_rp_10bit_tag(struct pci_dev *dev)
>   2097	{
>   2098		u8 support = 1;
>   2099		u32 cap;
>   2100		int ret;
>   2101	
>   2102		if (!pci_is_pcie(dev))
>   2103			return;
>   2104	
>   2105		if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
>   2106			return;
>   2107	
>   2108		if (dev->subordinate == NULL)
>   2109			return;
>   2110	
>   2111		pci_10bit_tag_comp_support(dev, &support);
>   2112		if (!support)
>   2113			return;
>   2114	
>   2115		/*
>   2116		 * PCIe spec 5.0r1.0 section 2.2.6.2 implementation note
>   2117		 * In configurations where a Requester with 10-Bit Tag Requester capability
>   2118		 * needs to target multiple Completers, one needs to ensure that the
>   2119		 * Requester sends 10-Bit Tag Requests only to Completers that have 10-Bit
>   2120		 * Tag Completer capability. So we enable 10-Bit Tag Requester for root port
>   2121		 * only when the devices under the root port support 10-Bit Tag Completer.
>   2122		 */
>   2123		pci_walk_bus(dev->subordinate, pci_10bit_tag_comp_support, &support);
>   2124		if (!support)
>   2125			return;
>   2126	
>   2127		ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
>   2128		if (ret)
>   2129			return;
>   2130	
>   2131		if (!(cap & PCI_EXP_DEVCAP2_10BIT_TAG_REQ))
>   2132			return;
>   2133	
>   2134		pci_info(dev, "enabling 10-Bit Tag Requester\n");
>   2135		pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
>   2136					 PCI_EXP_DEVCTL2_10BIT_TAG_REQ_EN);
>   2137	}
>   2138	
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
>
diff mbox series

Patch

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index ef7c466..056b73d 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -459,6 +459,7 @@  static inline void pci_dpc_init(struct pci_dev *pdev) {}
 void pcie_walk_rcec(struct pci_dev *rcec,
 		    int (*cb)(struct pci_dev *, void *),
 		    void *userdata);
+void pci_configure_rp_10bit_tag(struct pci_dev *dev);
 #else
 static inline void pci_rcec_init(struct pci_dev *dev) {}
 static inline void pci_rcec_exit(struct pci_dev *dev) {}
@@ -466,6 +467,7 @@  static inline void pcie_link_rcec(struct pci_dev *rcec) {}
 static inline void pcie_walk_rcec(struct pci_dev *rcec,
 				  int (*cb)(struct pci_dev *, void *),
 				  void *userdata) {}
+static inline void pci_configure_rp_10bit_tag(struct pci_dev *dev) {}
 #endif
 
 #ifdef CONFIG_PCI_ATS
diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c
index c7ff1ee..3af4733 100644
--- a/drivers/pci/pcie/portdrv_pci.c
+++ b/drivers/pci/pcie/portdrv_pci.c
@@ -111,6 +111,9 @@  static int pcie_portdrv_probe(struct pci_dev *dev,
 	     (type != PCI_EXP_TYPE_RC_EC)))
 		return -ENODEV;
 
+	if (type == PCI_EXP_TYPE_ROOT_PORT)
+		pci_configure_rp_10bit_tag(dev);
+
 	if (type == PCI_EXP_TYPE_RC_EC)
 		pcie_link_rcec(dev);
 
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 3efe1cc..73105c3 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -2051,6 +2051,92 @@  int pci_configure_extended_tags(struct pci_dev *dev, void *ign)
 	return 0;
 }
 
+static int pci_10bit_tag_comp_support(struct pci_dev *dev, void *data)
+{
+	u8 *support = data;
+	int ret;
+	u32 cap;
+
+	if (*support == 0)
+		return 0;
+
+	if (!pci_is_pcie(dev)) {
+		*support = 0;
+		return 0;
+	}
+
+	/*
+	 * PCIe spec 5.0r1.0 section 2.2.6.2 implementation note
+	 * For configurations where a Requester with 10-Bit Tag Requester capability
+	 * targets Completers where some do and some do not have 10-Bit Tag
+	 * Completer capability, how the Requester determines which NPRs include
+	 * 10-Bit Tags is outside the scope of this specification.  So we do not consider
+	 * hotplug scenario.
+	 */
+	if (dev->is_hotplug_bridge) {
+		*support = 0;
+		return 0;
+	}
+
+	ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
+	if (ret) {
+		*support = 0;
+		return 0;
+	}
+
+	if (!(cap & PCI_EXP_DEVCAP2_10BIT_TAG_COMP)) {
+		*support = 0;
+		return 0;
+	}
+
+
+	return 0;
+}
+
+void pci_configure_rp_10bit_tag(struct pci_dev *dev)
+{
+	u8 support = 1;
+	u32 cap;
+	int ret;
+
+	if (!pci_is_pcie(dev))
+		return;
+
+	if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
+		return;
+
+	if (dev->subordinate == NULL)
+		return;
+
+	pci_10bit_tag_comp_support(dev, &support);
+	if (!support)
+		return;
+
+	/*
+	 * PCIe spec 5.0r1.0 section 2.2.6.2 implementation note
+	 * In configurations where a Requester with 10-Bit Tag Requester capability
+	 * needs to target multiple Completers, one needs to ensure that the
+	 * Requester sends 10-Bit Tag Requests only to Completers that have 10-Bit
+	 * Tag Completer capability. So we enable 10-Bit Tag Requester for root port
+	 * only when the devices under the root port support 10-Bit Tag Completer.
+	 */
+	pci_walk_bus(dev->subordinate, pci_10bit_tag_comp_support, &support);
+	if (!support)
+		return;
+
+	ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
+	if (ret)
+		return;
+
+	if (!(cap & PCI_EXP_DEVCAP2_10BIT_TAG_REQ))
+		return;
+
+	pci_info(dev, "enabling 10-Bit Tag Requester\n");
+	pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
+				 PCI_EXP_DEVCTL2_10BIT_TAG_REQ_EN);
+}
+
+
 static void pci_configure_10bit_tags(struct pci_dev *dev)
 {
 	u32 cap;