Merge tag 's390-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add support for multi-function devices in pci code.

 - Enable PF-VF linking for architectures using the pdev->no_vf_scan
   flag (currently just s390).

 - Add reipl from NVMe support.

 - Get rid of critical section cleanup in entry.S.

 - Refactor PNSO CHSC (perform network subchannel operation) in cio and
   qeth.

 - QDIO interrupts and error handling fixes and improvements, more
   refactoring changes.

 - Align ioremap() with generic code.

 - Accept requests without the prefetch bit set in vfio-ccw.

 - Enable path handling via two new regions in vfio-ccw.

 - Other small fixes and improvements all over the code.

* tag 's390-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (52 commits)
  vfio-ccw: make vfio_ccw_regops variables declarations static
  vfio-ccw: Add trace for CRW event
  vfio-ccw: Wire up the CRW irq and CRW region
  vfio-ccw: Introduce a new CRW region
  vfio-ccw: Refactor IRQ handlers
  vfio-ccw: Introduce a new schib region
  vfio-ccw: Refactor the unregister of the async regions
  vfio-ccw: Register a chp_event callback for vfio-ccw
  vfio-ccw: Introduce new helper functions to free/destroy regions
  vfio-ccw: document possible errors
  vfio-ccw: Enable transparent CCW IPL from DASD
  s390/pci: Log new handle in clp_disable_fh()
  s390/cio, s390/qeth: cleanup PNSO CHSC
  s390/qdio: remove q->first_to_kick
  s390/qdio: fix up qdio_start_irq() kerneldoc
  s390: remove critical section cleanup from entry.S
  s390: add machine check SIGP
  s390/pci: ioremap() align with generic code
  s390/ap: introduce new ap function ap_get_qdev()
  Documentation/s390: Update / remove developerWorks web links
  ...

5 files changed, 227 insertions, 5 deletions

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index ed9597e37415..746030ae3b12 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3728,6 +3728,8 @@
 				may put more devices in an IOMMU group.
 		force_floating	[S390] Force usage of floating interrupts.
 		nomio		[S390] Do not use MIO instructions.
+		norid		[S390] ignore the RID field and force use of
+				one PCI domain per PCI function
 
 	pcie_aspm=	[PCIE] Forcibly enable or disable PCIe Active State Power
 			Management.
diff --git a/Documentation/s390/index.rst b/Documentation/s390/index.rst
index f7af2061e406..cf71df5776b4 100644
--- a/Documentation/s390/index.rst
+++ b/Documentation/s390/index.rst
@@ -15,6 +15,7 @@ s390 Architecture
     vfio-ccw
     zfcpdump
     common_io
+    pci
 
     text_files
 
diff --git a/Documentation/s390/pci.rst b/Documentation/s390/pci.rst
new file mode 100644
index 000000000000..492850bff316
--- /dev/null
+++ b/Documentation/s390/pci.rst
@@ -0,0 +1,125 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=========
+S/390 PCI
+=========
+
+Authors:
+        - Pierre Morel
+
+Copyright, IBM Corp. 2020
+
+
+Command line parameters and debugfs entries
+===========================================
+
+Command line parameters
+-----------------------
+
+* nomio
+
+  Do not use PCI Mapped I/O (MIO) instructions.
+
+* norid
+
+  Ignore the RID field and force use of one PCI domain per PCI function.
+
+debugfs entries
+---------------
+
+The S/390 debug feature (s390dbf) generates views to hold various debug results in sysfs directories of the form:
+
+ * /sys/kernel/debug/s390dbf/pci_*/
+
+For example:
+
+  - /sys/kernel/debug/s390dbf/pci_msg/sprintf
+    Holds messages from the processing of PCI events, like machine check handling
+    and setting of global functionality, like UID checking.
+
+  Change the level of logging to be more or less verbose by piping
+  a number between 0 and 6 to  /sys/kernel/debug/s390dbf/pci_*/level. For
+  details, see the documentation on the S/390 debug feature at
+  Documentation/s390/s390dbf.rst.
+
+Sysfs entries
+=============
+
+Entries specific to zPCI functions and entries that hold zPCI information.
+
+* /sys/bus/pci/slots/XXXXXXXX
+
+  The slot entries are set up using the function identifier (FID) of the
+  PCI function.
+
+  - /sys/bus/pci/slots/XXXXXXXX/power
+
+  A physical function that currently supports a virtual function cannot be
+  powered off until all virtual functions are removed with:
+  echo 0 > /sys/bus/pci/devices/XXXX:XX:XX.X/sriov_numvf
+
+* /sys/bus/pci/devices/XXXX:XX:XX.X/
+
+  - function_id
+    A zPCI function identifier that uniquely identifies the function in the Z server.
+
+  - function_handle
+    Low-level identifier used for a configured PCI function.
+    It might be useful for debuging.
+
+  - pchid
+    Model-dependent location of the I/O adapter.
+
+  - pfgid
+    PCI function group ID, functions that share identical functionality
+    use a common identifier.
+    A PCI group defines interrupts, IOMMU, IOTLB, and DMA specifics.
+
+  - vfn
+    The virtual function number, from 1 to N for virtual functions,
+    0 for physical functions.
+
+  - pft
+    The PCI function type
+
+  - port
+    The port corresponds to the physical port the function is attached to.
+    It also gives an indication of the physical function a virtual function
+    is attached to.
+
+  - uid
+    The unique identifier (UID) is defined when configuring an LPAR and is
+    unique in the LPAR.
+
+  - pfip/segmentX
+    The segments determine the isolation of a function.
+    They correspond to the physical path to the function.
+    The more the segments are different, the more the functions are isolated.
+
+Enumeration and hotplug
+=======================
+
+The PCI address consists of four parts: domain, bus, device and function,
+and is of this form: DDDD:BB:dd.f
+
+* When not using multi-functions (norid is set, or the firmware does not
+  support multi-functions):
+
+  - There is only one function per domain.
+
+  - The domain is set from the zPCI function's UID as defined during the
+    LPAR creation.
+
+* When using multi-functions (norid parameter is not set),
+  zPCI functions are addressed differently:
+
+  - There is still only one bus per domain.
+
+  - There can be up to 256 functions per bus.
+
+  - The domain part of the address of all functions for
+    a multi-Function device is set from the zPCI function's UID as defined
+    in the LPAR creation for the function zero.
+
+  - New functions will only be ready for use after the function zero
+    (the function with devfn 0) has been enumerated.
diff --git a/Documentation/s390/vfio-ccw.rst b/Documentation/s390/vfio-ccw.rst
index fca9c4f5bd9c..8aad08a8b8a5 100644
--- a/Documentation/s390/vfio-ccw.rst
+++ b/Documentation/s390/vfio-ccw.rst
@@ -204,15 +204,44 @@ definition of the region is::
 	  __u32   ret_code;
   } __packed;
 
+This region is always available.
+
 While starting an I/O request, orb_area should be filled with the
 guest ORB, and scsw_area should be filled with the SCSW of the Virtual
 Subchannel.
 
 irb_area stores the I/O result.
 
-ret_code stores a return code for each access of the region.
+ret_code stores a return code for each access of the region. The following
+values may occur:
+
+``0``
+  The operation was successful.
+
+``-EOPNOTSUPP``
+  The orb specified transport mode or an unidentified IDAW format, or the
+  scsw specified a function other than the start function.
+
+``-EIO``
+  A request was issued while the device was not in a state ready to accept
+  requests, or an internal error occurred.
+
+``-EBUSY``
+  The subchannel was status pending or busy, or a request is already active.
+
+``-EAGAIN``
+  A request was being processed, and the caller should retry.
+
+``-EACCES``
+  The channel path(s) used for the I/O were found to be not operational.
+
+``-ENODEV``
+  The device was found to be not operational.
+
+``-EINVAL``
+  The orb specified a chain longer than 255 ccws, or an internal error
+  occurred.
 
-This region is always available.
 
 vfio-ccw cmd region
 -------------------
@@ -231,6 +260,64 @@ This region is exposed via region type VFIO_REGION_SUBTYPE_CCW_ASYNC_CMD.
 
 Currently, CLEAR SUBCHANNEL and HALT SUBCHANNEL use this region.
 
+command specifies the command to be issued; ret_code stores a return code
+for each access of the region. The following values may occur:
+
+``0``
+  The operation was successful.
+
+``-ENODEV``
+  The device was found to be not operational.
+
+``-EINVAL``
+  A command other than halt or clear was specified.
+
+``-EIO``
+  A request was issued while the device was not in a state ready to accept
+  requests.
+
+``-EAGAIN``
+  A request was being processed, and the caller should retry.
+
+``-EBUSY``
+  The subchannel was status pending or busy while processing a halt request.
+
+vfio-ccw schib region
+---------------------
+
+The vfio-ccw schib region is used to return Subchannel-Information
+Block (SCHIB) data to userspace::
+
+  struct ccw_schib_region {
+  #define SCHIB_AREA_SIZE 52
+         __u8 schib_area[SCHIB_AREA_SIZE];
+  } __packed;
+
+This region is exposed via region type VFIO_REGION_SUBTYPE_CCW_SCHIB.
+
+Reading this region triggers a STORE SUBCHANNEL to be issued to the
+associated hardware.
+
+vfio-ccw crw region
+---------------------
+
+The vfio-ccw crw region is used to return Channel Report Word (CRW)
+data to userspace::
+
+  struct ccw_crw_region {
+         __u32 crw;
+         __u32 pad;
+  } __packed;
+
+This region is exposed via region type VFIO_REGION_SUBTYPE_CCW_CRW.
+
+Reading this region returns a CRW if one that is relevant for this
+subchannel (e.g. one reporting changes in channel path state) is
+pending, or all zeroes if not. If multiple CRWs are pending (including
+possibly chained CRWs), reading this region again will return the next
+one, until no more CRWs are pending and zeroes are returned. This is
+similar to how STORE CHANNEL REPORT WORD works.
+
 vfio-ccw operation details
 --------------------------
 
@@ -333,7 +420,14 @@ through DASD/ECKD device online in a guest now and use it as a block
 device.
 
 The current code allows the guest to start channel programs via
-START SUBCHANNEL, and to issue HALT SUBCHANNEL and CLEAR SUBCHANNEL.
+START SUBCHANNEL, and to issue HALT SUBCHANNEL, CLEAR SUBCHANNEL,
+and STORE SUBCHANNEL.
+
+Currently all channel programs are prefetched, regardless of the
+p-bit setting in the ORB.  As a result, self modifying channel
+programs are not supported.  For this reason, IPL has to be handled as
+a special case by a userspace/guest program; this has been implemented
+in QEMU's s390-ccw bios as of QEMU 4.1.
 
 vfio-ccw supports classic (command mode) channel I/O only. Transport
 mode (HPF) is not supported.
diff --git a/Documentation/s390/zfcpdump.rst b/Documentation/s390/zfcpdump.rst
index 54e8e7caf7e7..a61de7aa8778 100644
--- a/Documentation/s390/zfcpdump.rst
+++ b/Documentation/s390/zfcpdump.rst
@@ -46,5 +46,5 @@ initramfs with a user space application that writes the dump to a SCSI
 partition.
 
 For more information on how to use zfcpdump refer to the s390 'Using the Dump
-Tools book', which is available from
-http://www.ibm.com/developerworks/linux/linux390.
+Tools' book, which is available from IBM Knowledge Center:
+https://www.ibm.com/support/knowledgecenter/linuxonibm/liaaf/lnz_r_dt.html