Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1135 insertions, 0 deletions

diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
new file mode 100644
index 000000000..d34d5813d
--- /dev/null
+++ b/arch/s390/pci/pci.c
@@ -0,0 +1,1135 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright IBM Corp. 2012
+ *
+ * Author(s):
+ *   Jan Glauber <jang@linux.vnet.ibm.com>
+ *
+ * The System z PCI code is a rewrite from a prototype by
+ * the following people (Kudoz!):
+ *   Alexander Schmidt
+ *   Christoph Raisch
+ *   Hannes Hering
+ *   Hoang-Nam Nguyen
+ *   Jan-Bernd Themann
+ *   Stefan Roscher
+ *   Thomas Klein
+ */
+
+#define KMSG_COMPONENT "zpci"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/delay.h>
+#include <linux/seq_file.h>
+#include <linux/jump_label.h>
+#include <linux/pci.h>
+#include <linux/printk.h>
+
+#include <asm/isc.h>
+#include <asm/airq.h>
+#include <asm/facility.h>
+#include <asm/pci_insn.h>
+#include <asm/pci_clp.h>
+#include <asm/pci_dma.h>
+
+#include "pci_bus.h"
+#include "pci_iov.h"
+
+/* list of all detected zpci devices */
+static LIST_HEAD(zpci_list);
+static DEFINE_SPINLOCK(zpci_list_lock);
+
+static DECLARE_BITMAP(zpci_domain, ZPCI_DOMAIN_BITMAP_SIZE);
+static DEFINE_SPINLOCK(zpci_domain_lock);
+
+#define ZPCI_IOMAP_ENTRIES						\
+	min(((unsigned long) ZPCI_NR_DEVICES * PCI_STD_NUM_BARS / 2),	\
+	    ZPCI_IOMAP_MAX_ENTRIES)
+
+unsigned int s390_pci_no_rid;
+
+static DEFINE_SPINLOCK(zpci_iomap_lock);
+static unsigned long *zpci_iomap_bitmap;
+struct zpci_iomap_entry *zpci_iomap_start;
+EXPORT_SYMBOL_GPL(zpci_iomap_start);
+
+DEFINE_STATIC_KEY_FALSE(have_mio);
+
+static struct kmem_cache *zdev_fmb_cache;
+
+/* AEN structures that must be preserved over KVM module re-insertion */
+union zpci_sic_iib *zpci_aipb;
+EXPORT_SYMBOL_GPL(zpci_aipb);
+struct airq_iv *zpci_aif_sbv;
+EXPORT_SYMBOL_GPL(zpci_aif_sbv);
+
+struct zpci_dev *get_zdev_by_fid(u32 fid)
+{
+	struct zpci_dev *tmp, *zdev = NULL;
+
+	spin_lock(&zpci_list_lock);
+	list_for_each_entry(tmp, &zpci_list, entry) {
+		if (tmp->fid == fid) {
+			zdev = tmp;
+			zpci_zdev_get(zdev);
+			break;
+		}
+	}
+	spin_unlock(&zpci_list_lock);
+	return zdev;
+}
+
+void zpci_remove_reserved_devices(void)
+{
+	struct zpci_dev *tmp, *zdev;
+	enum zpci_state state;
+	LIST_HEAD(remove);
+
+	spin_lock(&zpci_list_lock);
+	list_for_each_entry_safe(zdev, tmp, &zpci_list, entry) {
+		if (zdev->state == ZPCI_FN_STATE_STANDBY &&
+		    !clp_get_state(zdev->fid, &state) &&
+		    state == ZPCI_FN_STATE_RESERVED)
+			list_move_tail(&zdev->entry, &remove);
+	}
+	spin_unlock(&zpci_list_lock);
+
+	list_for_each_entry_safe(zdev, tmp, &remove, entry)
+		zpci_device_reserved(zdev);
+}
+
+int pci_domain_nr(struct pci_bus *bus)
+{
+	return ((struct zpci_bus *) bus->sysdata)->domain_nr;
+}
+EXPORT_SYMBOL_GPL(pci_domain_nr);
+
+int pci_proc_domain(struct pci_bus *bus)
+{
+	return pci_domain_nr(bus);
+}
+EXPORT_SYMBOL_GPL(pci_proc_domain);
+
+/* Modify PCI: Register I/O address translation parameters */
+int zpci_register_ioat(struct zpci_dev *zdev, u8 dmaas,
+		       u64 base, u64 limit, u64 iota, u8 *status)
+{
+	u64 req = ZPCI_CREATE_REQ(zdev->fh, dmaas, ZPCI_MOD_FC_REG_IOAT);
+	struct zpci_fib fib = {0};
+	u8 cc;
+
+	WARN_ON_ONCE(iota & 0x3fff);
+	fib.pba = base;
+	fib.pal = limit;
+	fib.iota = iota | ZPCI_IOTA_RTTO_FLAG;
+	fib.gd = zdev->gisa;
+	cc = zpci_mod_fc(req, &fib, status);
+	if (cc)
+		zpci_dbg(3, "reg ioat fid:%x, cc:%d, status:%d\n", zdev->fid, cc, *status);
+	return cc;
+}
+EXPORT_SYMBOL_GPL(zpci_register_ioat);
+
+/* Modify PCI: Unregister I/O address translation parameters */
+int zpci_unregister_ioat(struct zpci_dev *zdev, u8 dmaas)
+{
+	u64 req = ZPCI_CREATE_REQ(zdev->fh, dmaas, ZPCI_MOD_FC_DEREG_IOAT);
+	struct zpci_fib fib = {0};
+	u8 cc, status;
+
+	fib.gd = zdev->gisa;
+
+	cc = zpci_mod_fc(req, &fib, &status);
+	if (cc)
+		zpci_dbg(3, "unreg ioat fid:%x, cc:%d, status:%d\n", zdev->fid, cc, status);
+	return cc;
+}
+
+/* Modify PCI: Set PCI function measurement parameters */
+int zpci_fmb_enable_device(struct zpci_dev *zdev)
+{
+	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_SET_MEASURE);
+	struct zpci_fib fib = {0};
+	u8 cc, status;
+
+	if (zdev->fmb || sizeof(*zdev->fmb) < zdev->fmb_length)
+		return -EINVAL;
+
+	zdev->fmb = kmem_cache_zalloc(zdev_fmb_cache, GFP_KERNEL);
+	if (!zdev->fmb)
+		return -ENOMEM;
+	WARN_ON((u64) zdev->fmb & 0xf);
+
+	/* reset software counters */
+	atomic64_set(&zdev->allocated_pages, 0);
+	atomic64_set(&zdev->mapped_pages, 0);
+	atomic64_set(&zdev->unmapped_pages, 0);
+
+	fib.fmb_addr = virt_to_phys(zdev->fmb);
+	fib.gd = zdev->gisa;
+	cc = zpci_mod_fc(req, &fib, &status);
+	if (cc) {
+		kmem_cache_free(zdev_fmb_cache, zdev->fmb);
+		zdev->fmb = NULL;
+	}
+	return cc ? -EIO : 0;
+}
+
+/* Modify PCI: Disable PCI function measurement */
+int zpci_fmb_disable_device(struct zpci_dev *zdev)
+{
+	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_SET_MEASURE);
+	struct zpci_fib fib = {0};
+	u8 cc, status;
+
+	if (!zdev->fmb)
+		return -EINVAL;
+
+	fib.gd = zdev->gisa;
+
+	/* Function measurement is disabled if fmb address is zero */
+	cc = zpci_mod_fc(req, &fib, &status);
+	if (cc == 3) /* Function already gone. */
+		cc = 0;
+
+	if (!cc) {
+		kmem_cache_free(zdev_fmb_cache, zdev->fmb);
+		zdev->fmb = NULL;
+	}
+	return cc ? -EIO : 0;
+}
+
+static int zpci_cfg_load(struct zpci_dev *zdev, int offset, u32 *val, u8 len)
+{
+	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
+	u64 data;
+	int rc;
+
+	rc = __zpci_load(&data, req, offset);
+	if (!rc) {
+		data = le64_to_cpu((__force __le64) data);
+		data >>= (8 - len) * 8;
+		*val = (u32) data;
+	} else
+		*val = 0xffffffff;
+	return rc;
+}
+
+static int zpci_cfg_store(struct zpci_dev *zdev, int offset, u32 val, u8 len)
+{
+	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
+	u64 data = val;
+	int rc;
+
+	data <<= (8 - len) * 8;
+	data = (__force u64) cpu_to_le64(data);
+	rc = __zpci_store(data, req, offset);
+	return rc;
+}
+
+resource_size_t pcibios_align_resource(void *data, const struct resource *res,
+				       resource_size_t size,
+				       resource_size_t align)
+{
+	return 0;
+}
+
+/* combine single writes by using store-block insn */
+void __iowrite64_copy(void __iomem *to, const void *from, size_t count)
+{
+       zpci_memcpy_toio(to, from, count);
+}
+
+void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,
+			   unsigned long prot)
+{
+	/*
+	 * When PCI MIO instructions are unavailable the "physical" address
+	 * encodes a hint for accessing the PCI memory space it represents.
+	 * Just pass it unchanged such that ioread/iowrite can decode it.
+	 */
+	if (!static_branch_unlikely(&have_mio))
+		return (void __iomem *)phys_addr;
+
+	return generic_ioremap_prot(phys_addr, size, __pgprot(prot));
+}
+EXPORT_SYMBOL(ioremap_prot);
+
+void iounmap(volatile void __iomem *addr)
+{
+	if (static_branch_likely(&have_mio))
+		generic_iounmap(addr);
+}
+EXPORT_SYMBOL(iounmap);
+
+/* Create a virtual mapping cookie for a PCI BAR */
+static void __iomem *pci_iomap_range_fh(struct pci_dev *pdev, int bar,
+					unsigned long offset, unsigned long max)
+{
+	struct zpci_dev *zdev =	to_zpci(pdev);
+	int idx;
+
+	idx = zdev->bars[bar].map_idx;
+	spin_lock(&zpci_iomap_lock);
+	/* Detect overrun */
+	WARN_ON(!++zpci_iomap_start[idx].count);
+	zpci_iomap_start[idx].fh = zdev->fh;
+	zpci_iomap_start[idx].bar = bar;
+	spin_unlock(&zpci_iomap_lock);
+
+	return (void __iomem *) ZPCI_ADDR(idx) + offset;
+}
+
+static void __iomem *pci_iomap_range_mio(struct pci_dev *pdev, int bar,
+					 unsigned long offset,
+					 unsigned long max)
+{
+	unsigned long barsize = pci_resource_len(pdev, bar);
+	struct zpci_dev *zdev = to_zpci(pdev);
+	void __iomem *iova;
+
+	iova = ioremap((unsigned long) zdev->bars[bar].mio_wt, barsize);
+	return iova ? iova + offset : iova;
+}
+
+void __iomem *pci_iomap_range(struct pci_dev *pdev, int bar,
+			      unsigned long offset, unsigned long max)
+{
+	if (bar >= PCI_STD_NUM_BARS || !pci_resource_len(pdev, bar))
+		return NULL;
+
+	if (static_branch_likely(&have_mio))
+		return pci_iomap_range_mio(pdev, bar, offset, max);
+	else
+		return pci_iomap_range_fh(pdev, bar, offset, max);
+}
+EXPORT_SYMBOL(pci_iomap_range);
+
+void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
+{
+	return pci_iomap_range(dev, bar, 0, maxlen);
+}
+EXPORT_SYMBOL(pci_iomap);
+
+static void __iomem *pci_iomap_wc_range_mio(struct pci_dev *pdev, int bar,
+					    unsigned long offset, unsigned long max)
+{
+	unsigned long barsize = pci_resource_len(pdev, bar);
+	struct zpci_dev *zdev = to_zpci(pdev);
+	void __iomem *iova;
+
+	iova = ioremap((unsigned long) zdev->bars[bar].mio_wb, barsize);
+	return iova ? iova + offset : iova;
+}
+
+void __iomem *pci_iomap_wc_range(struct pci_dev *pdev, int bar,
+				 unsigned long offset, unsigned long max)
+{
+	if (bar >= PCI_STD_NUM_BARS || !pci_resource_len(pdev, bar))
+		return NULL;
+
+	if (static_branch_likely(&have_mio))
+		return pci_iomap_wc_range_mio(pdev, bar, offset, max);
+	else
+		return pci_iomap_range_fh(pdev, bar, offset, max);
+}
+EXPORT_SYMBOL(pci_iomap_wc_range);
+
+void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long maxlen)
+{
+	return pci_iomap_wc_range(dev, bar, 0, maxlen);
+}
+EXPORT_SYMBOL(pci_iomap_wc);
+
+static void pci_iounmap_fh(struct pci_dev *pdev, void __iomem *addr)
+{
+	unsigned int idx = ZPCI_IDX(addr);
+
+	spin_lock(&zpci_iomap_lock);
+	/* Detect underrun */
+	WARN_ON(!zpci_iomap_start[idx].count);
+	if (!--zpci_iomap_start[idx].count) {
+		zpci_iomap_start[idx].fh = 0;
+		zpci_iomap_start[idx].bar = 0;
+	}
+	spin_unlock(&zpci_iomap_lock);
+}
+
+static void pci_iounmap_mio(struct pci_dev *pdev, void __iomem *addr)
+{
+	iounmap(addr);
+}
+
+void pci_iounmap(struct pci_dev *pdev, void __iomem *addr)
+{
+	if (static_branch_likely(&have_mio))
+		pci_iounmap_mio(pdev, addr);
+	else
+		pci_iounmap_fh(pdev, addr);
+}
+EXPORT_SYMBOL(pci_iounmap);
+
+static int pci_read(struct pci_bus *bus, unsigned int devfn, int where,
+		    int size, u32 *val)
+{
+	struct zpci_dev *zdev = zdev_from_bus(bus, devfn);
+
+	return (zdev) ? zpci_cfg_load(zdev, where, val, size) : -ENODEV;
+}
+
+static int pci_write(struct pci_bus *bus, unsigned int devfn, int where,
+		     int size, u32 val)
+{
+	struct zpci_dev *zdev = zdev_from_bus(bus, devfn);
+
+	return (zdev) ? zpci_cfg_store(zdev, where, val, size) : -ENODEV;
+}
+
+static struct pci_ops pci_root_ops = {
+	.read = pci_read,
+	.write = pci_write,
+};
+
+static void zpci_map_resources(struct pci_dev *pdev)
+{
+	struct zpci_dev *zdev = to_zpci(pdev);
+	resource_size_t len;
+	int i;
+
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+		len = pci_resource_len(pdev, i);
+		if (!len)
+			continue;
+
+		if (zpci_use_mio(zdev))
+			pdev->resource[i].start =
+				(resource_size_t __force) zdev->bars[i].mio_wt;
+		else
+			pdev->resource[i].start = (resource_size_t __force)
+				pci_iomap_range_fh(pdev, i, 0, 0);
+		pdev->resource[i].end = pdev->resource[i].start + len - 1;
+	}
+
+	zpci_iov_map_resources(pdev);
+}
+
+static void zpci_unmap_resources(struct pci_dev *pdev)
+{
+	struct zpci_dev *zdev = to_zpci(pdev);
+	resource_size_t len;
+	int i;
+
+	if (zpci_use_mio(zdev))
+		return;
+
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+		len = pci_resource_len(pdev, i);
+		if (!len)
+			continue;
+		pci_iounmap_fh(pdev, (void __iomem __force *)
+			       pdev->resource[i].start);
+	}
+}
+
+static int zpci_alloc_iomap(struct zpci_dev *zdev)
+{
+	unsigned long entry;
+
+	spin_lock(&zpci_iomap_lock);
+	entry = find_first_zero_bit(zpci_iomap_bitmap, ZPCI_IOMAP_ENTRIES);
+	if (entry == ZPCI_IOMAP_ENTRIES) {
+		spin_unlock(&zpci_iomap_lock);
+		return -ENOSPC;
+	}
+	set_bit(entry, zpci_iomap_bitmap);
+	spin_unlock(&zpci_iomap_lock);
+	return entry;
+}
+
+static void zpci_free_iomap(struct zpci_dev *zdev, int entry)
+{
+	spin_lock(&zpci_iomap_lock);
+	memset(&zpci_iomap_start[entry], 0, sizeof(struct zpci_iomap_entry));
+	clear_bit(entry, zpci_iomap_bitmap);
+	spin_unlock(&zpci_iomap_lock);
+}
+
+static void zpci_do_update_iomap_fh(struct zpci_dev *zdev, u32 fh)
+{
+	int bar, idx;
+
+	spin_lock(&zpci_iomap_lock);
+	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
+		if (!zdev->bars[bar].size)
+			continue;
+		idx = zdev->bars[bar].map_idx;
+		if (!zpci_iomap_start[idx].count)
+			continue;
+		WRITE_ONCE(zpci_iomap_start[idx].fh, zdev->fh);
+	}
+	spin_unlock(&zpci_iomap_lock);
+}
+
+void zpci_update_fh(struct zpci_dev *zdev, u32 fh)
+{
+	if (!fh || zdev->fh == fh)
+		return;
+
+	zdev->fh = fh;
+	if (zpci_use_mio(zdev))
+		return;
+	if (zdev->has_resources && zdev_enabled(zdev))
+		zpci_do_update_iomap_fh(zdev, fh);
+}
+
+static struct resource *__alloc_res(struct zpci_dev *zdev, unsigned long start,
+				    unsigned long size, unsigned long flags)
+{
+	struct resource *r;
+
+	r = kzalloc(sizeof(*r), GFP_KERNEL);
+	if (!r)
+		return NULL;
+
+	r->start = start;
+	r->end = r->start + size - 1;
+	r->flags = flags;
+	r->name = zdev->res_name;
+
+	if (request_resource(&iomem_resource, r)) {
+		kfree(r);
+		return NULL;
+	}
+	return r;
+}
+
+int zpci_setup_bus_resources(struct zpci_dev *zdev)
+{
+	unsigned long addr, size, flags;
+	struct resource *res;
+	int i, entry;
+
+	snprintf(zdev->res_name, sizeof(zdev->res_name),
+		 "PCI Bus %04x:%02x", zdev->uid, ZPCI_BUS_NR);
+
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+		if (!zdev->bars[i].size)
+			continue;
+		entry = zpci_alloc_iomap(zdev);
+		if (entry < 0)
+			return entry;
+		zdev->bars[i].map_idx = entry;
+
+		/* only MMIO is supported */
+		flags = IORESOURCE_MEM;
+		if (zdev->bars[i].val & 8)
+			flags |= IORESOURCE_PREFETCH;
+		if (zdev->bars[i].val & 4)
+			flags |= IORESOURCE_MEM_64;
+
+		if (zpci_use_mio(zdev))
+			addr = (unsigned long) zdev->bars[i].mio_wt;
+		else
+			addr = ZPCI_ADDR(entry);
+		size = 1UL << zdev->bars[i].size;
+
+		res = __alloc_res(zdev, addr, size, flags);
+		if (!res) {
+			zpci_free_iomap(zdev, entry);
+			return -ENOMEM;
+		}
+		zdev->bars[i].res = res;
+	}
+	zdev->has_resources = 1;
+
+	return 0;
+}
+
+static void zpci_cleanup_bus_resources(struct zpci_dev *zdev)
+{
+	struct resource *res;
+	int i;
+
+	pci_lock_rescan_remove();
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+		res = zdev->bars[i].res;
+		if (!res)
+			continue;
+
+		release_resource(res);
+		pci_bus_remove_resource(zdev->zbus->bus, res);
+		zpci_free_iomap(zdev, zdev->bars[i].map_idx);
+		zdev->bars[i].res = NULL;
+		kfree(res);
+	}
+	zdev->has_resources = 0;
+	pci_unlock_rescan_remove();
+}
+
+int pcibios_device_add(struct pci_dev *pdev)
+{
+	struct zpci_dev *zdev = to_zpci(pdev);
+	struct resource *res;
+	int i;
+
+	/* The pdev has a reference to the zdev via its bus */
+	zpci_zdev_get(zdev);
+	if (pdev->is_physfn)
+		pdev->no_vf_scan = 1;
+
+	pdev->dev.groups = zpci_attr_groups;
+	pdev->dev.dma_ops = &s390_pci_dma_ops;
+	zpci_map_resources(pdev);
+
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+		res = &pdev->resource[i];
+		if (res->parent || !res->flags)
+			continue;
+		pci_claim_resource(pdev, i);
+	}
+
+	return 0;
+}
+
+void pcibios_release_device(struct pci_dev *pdev)
+{
+	struct zpci_dev *zdev = to_zpci(pdev);
+
+	zpci_unmap_resources(pdev);
+	zpci_zdev_put(zdev);
+}
+
+int pcibios_enable_device(struct pci_dev *pdev, int mask)
+{
+	struct zpci_dev *zdev = to_zpci(pdev);
+
+	zpci_debug_init_device(zdev, dev_name(&pdev->dev));
+	zpci_fmb_enable_device(zdev);
+
+	return pci_enable_resources(pdev, mask);
+}
+
+void pcibios_disable_device(struct pci_dev *pdev)
+{
+	struct zpci_dev *zdev = to_zpci(pdev);
+
+	zpci_fmb_disable_device(zdev);
+	zpci_debug_exit_device(zdev);
+}
+
+static int __zpci_register_domain(int domain)
+{
+	spin_lock(&zpci_domain_lock);
+	if (test_bit(domain, zpci_domain)) {
+		spin_unlock(&zpci_domain_lock);
+		pr_err("Domain %04x is already assigned\n", domain);
+		return -EEXIST;
+	}
+	set_bit(domain, zpci_domain);
+	spin_unlock(&zpci_domain_lock);
+	return domain;
+}
+
+static int __zpci_alloc_domain(void)
+{
+	int domain;
+
+	spin_lock(&zpci_domain_lock);
+	/*
+	 * We can always auto allocate domains below ZPCI_NR_DEVICES.
+	 * There is either a free domain or we have reached the maximum in
+	 * which case we would have bailed earlier.
+	 */
+	domain = find_first_zero_bit(zpci_domain, ZPCI_NR_DEVICES);
+	set_bit(domain, zpci_domain);
+	spin_unlock(&zpci_domain_lock);
+	return domain;
+}
+
+int zpci_alloc_domain(int domain)
+{
+	if (zpci_unique_uid) {
+		if (domain)
+			return __zpci_register_domain(domain);
+		pr_warn("UID checking was active but no UID is provided: switching to automatic domain allocation\n");
+		update_uid_checking(false);
+	}
+	return __zpci_alloc_domain();
+}
+
+void zpci_free_domain(int domain)
+{
+	spin_lock(&zpci_domain_lock);
+	clear_bit(domain, zpci_domain);
+	spin_unlock(&zpci_domain_lock);
+}
+
+
+int zpci_enable_device(struct zpci_dev *zdev)
+{
+	u32 fh = zdev->fh;
+	int rc = 0;
+
+	if (clp_enable_fh(zdev, &fh, ZPCI_NR_DMA_SPACES))
+		rc = -EIO;
+	else
+		zpci_update_fh(zdev, fh);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(zpci_enable_device);
+
+int zpci_disable_device(struct zpci_dev *zdev)
+{
+	u32 fh = zdev->fh;
+	int cc, rc = 0;
+
+	cc = clp_disable_fh(zdev, &fh);
+	if (!cc) {
+		zpci_update_fh(zdev, fh);
+	} else if (cc == CLP_RC_SETPCIFN_ALRDY) {
+		pr_info("Disabling PCI function %08x had no effect as it was already disabled\n",
+			zdev->fid);
+		/* Function is already disabled - update handle */
+		rc = clp_refresh_fh(zdev->fid, &fh);
+		if (!rc) {
+			zpci_update_fh(zdev, fh);
+			rc = -EINVAL;
+		}
+	} else {
+		rc = -EIO;
+	}
+	return rc;
+}
+EXPORT_SYMBOL_GPL(zpci_disable_device);
+
+/**
+ * zpci_hot_reset_device - perform a reset of the given zPCI function
+ * @zdev: the slot which should be reset
+ *
+ * Performs a low level reset of the zPCI function. The reset is low level in
+ * the sense that the zPCI function can be reset without detaching it from the
+ * common PCI subsystem. The reset may be performed while under control of
+ * either DMA or IOMMU APIs in which case the existing DMA/IOMMU translation
+ * table is reinstated at the end of the reset.
+ *
+ * After the reset the functions internal state is reset to an initial state
+ * equivalent to its state during boot when first probing a driver.
+ * Consequently after reset the PCI function requires re-initialization via the
+ * common PCI code including re-enabling IRQs via pci_alloc_irq_vectors()
+ * and enabling the function via e.g.pci_enablde_device_flags().The caller
+ * must guard against concurrent reset attempts.
+ *
+ * In most cases this function should not be called directly but through
+ * pci_reset_function() or pci_reset_bus() which handle the save/restore and
+ * locking.
+ *
+ * Return: 0 on success and an error value otherwise
+ */
+int zpci_hot_reset_device(struct zpci_dev *zdev)
+{
+	u8 status;
+	int rc;
+
+	zpci_dbg(3, "rst fid:%x, fh:%x\n", zdev->fid, zdev->fh);
+	if (zdev_enabled(zdev)) {
+		/* Disables device access, DMAs and IRQs (reset state) */
+		rc = zpci_disable_device(zdev);
+		/*
+		 * Due to a z/VM vs LPAR inconsistency in the error state the
+		 * FH may indicate an enabled device but disable says the
+		 * device is already disabled don't treat it as an error here.
+		 */
+		if (rc == -EINVAL)
+			rc = 0;
+		if (rc)
+			return rc;
+	}
+
+	rc = zpci_enable_device(zdev);
+	if (rc)
+		return rc;
+
+	if (zdev->dma_table)
+		rc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
+					virt_to_phys(zdev->dma_table), &status);
+	else
+		rc = zpci_dma_init_device(zdev);
+	if (rc) {
+		zpci_disable_device(zdev);
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * zpci_create_device() - Create a new zpci_dev and add it to the zbus
+ * @fid: Function ID of the device to be created
+ * @fh: Current Function Handle of the device to be created
+ * @state: Initial state after creation either Standby or Configured
+ *
+ * Creates a new zpci device and adds it to its, possibly newly created, zbus
+ * as well as zpci_list.
+ *
+ * Returns: the zdev on success or an error pointer otherwise
+ */
+struct zpci_dev *zpci_create_device(u32 fid, u32 fh, enum zpci_state state)
+{
+	struct zpci_dev *zdev;
+	int rc;
+
+	zpci_dbg(1, "add fid:%x, fh:%x, c:%d\n", fid, fh, state);
+	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
+	if (!zdev)
+		return ERR_PTR(-ENOMEM);
+
+	/* FID and Function Handle are the static/dynamic identifiers */
+	zdev->fid = fid;
+	zdev->fh = fh;
+
+	/* Query function properties and update zdev */
+	rc = clp_query_pci_fn(zdev);
+	if (rc)
+		goto error;
+	zdev->state =  state;
+
+	kref_init(&zdev->kref);
+	mutex_init(&zdev->lock);
+	mutex_init(&zdev->kzdev_lock);
+
+	rc = zpci_init_iommu(zdev);
+	if (rc)
+		goto error;
+
+	rc = zpci_bus_device_register(zdev, &pci_root_ops);
+	if (rc)
+		goto error_destroy_iommu;
+
+	spin_lock(&zpci_list_lock);
+	list_add_tail(&zdev->entry, &zpci_list);
+	spin_unlock(&zpci_list_lock);
+
+	return zdev;
+
+error_destroy_iommu:
+	zpci_destroy_iommu(zdev);
+error:
+	zpci_dbg(0, "add fid:%x, rc:%d\n", fid, rc);
+	kfree(zdev);
+	return ERR_PTR(rc);
+}
+
+bool zpci_is_device_configured(struct zpci_dev *zdev)
+{
+	enum zpci_state state = zdev->state;
+
+	return state != ZPCI_FN_STATE_RESERVED &&
+		state != ZPCI_FN_STATE_STANDBY;
+}
+
+/**
+ * zpci_scan_configured_device() - Scan a freshly configured zpci_dev
+ * @zdev: The zpci_dev to be configured
+ * @fh: The general function handle supplied by the platform
+ *
+ * Given a device in the configuration state Configured, enables, scans and
+ * adds it to the common code PCI subsystem if possible. If any failure occurs,
+ * the zpci_dev is left disabled.
+ *
+ * Return: 0 on success, or an error code otherwise
+ */
+int zpci_scan_configured_device(struct zpci_dev *zdev, u32 fh)
+{
+	zpci_update_fh(zdev, fh);
+	return zpci_bus_scan_device(zdev);
+}
+
+/**
+ * zpci_deconfigure_device() - Deconfigure a zpci_dev
+ * @zdev: The zpci_dev to configure
+ *
+ * Deconfigure a zPCI function that is currently configured and possibly known
+ * to the common code PCI subsystem.
+ * If any failure occurs the device is left as is.
+ *
+ * Return: 0 on success, or an error code otherwise
+ */
+int zpci_deconfigure_device(struct zpci_dev *zdev)
+{
+	int rc;
+
+	if (zdev->zbus->bus)
+		zpci_bus_remove_device(zdev, false);
+
+	if (zdev->dma_table) {
+		rc = zpci_dma_exit_device(zdev);
+		if (rc)
+			return rc;
+	}
+	if (zdev_enabled(zdev)) {
+		rc = zpci_disable_device(zdev);
+		if (rc)
+			return rc;
+	}
+
+	rc = sclp_pci_deconfigure(zdev->fid);
+	zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, rc);
+	if (rc)
+		return rc;
+	zdev->state = ZPCI_FN_STATE_STANDBY;
+
+	return 0;
+}
+
+/**
+ * zpci_device_reserved() - Mark device as resverved
+ * @zdev: the zpci_dev that was reserved
+ *
+ * Handle the case that a given zPCI function was reserved by another system.
+ * After a call to this function the zpci_dev can not be found via
+ * get_zdev_by_fid() anymore but may still be accessible via existing
+ * references though it will not be functional anymore.
+ */
+void zpci_device_reserved(struct zpci_dev *zdev)
+{
+	if (zdev->has_hp_slot)
+		zpci_exit_slot(zdev);
+	/*
+	 * Remove device from zpci_list as it is going away. This also
+	 * makes sure we ignore subsequent zPCI events for this device.
+	 */
+	spin_lock(&zpci_list_lock);
+	list_del(&zdev->entry);
+	spin_unlock(&zpci_list_lock);
+	zdev->state = ZPCI_FN_STATE_RESERVED;
+	zpci_dbg(3, "rsv fid:%x\n", zdev->fid);
+	zpci_zdev_put(zdev);
+}
+
+void zpci_release_device(struct kref *kref)
+{
+	struct zpci_dev *zdev = container_of(kref, struct zpci_dev, kref);
+	int ret;
+
+	if (zdev->zbus->bus)
+		zpci_bus_remove_device(zdev, false);
+
+	if (zdev->dma_table)
+		zpci_dma_exit_device(zdev);
+	if (zdev_enabled(zdev))
+		zpci_disable_device(zdev);
+
+	switch (zdev->state) {
+	case ZPCI_FN_STATE_CONFIGURED:
+		ret = sclp_pci_deconfigure(zdev->fid);
+		zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret);
+		fallthrough;
+	case ZPCI_FN_STATE_STANDBY:
+		if (zdev->has_hp_slot)
+			zpci_exit_slot(zdev);
+		spin_lock(&zpci_list_lock);
+		list_del(&zdev->entry);
+		spin_unlock(&zpci_list_lock);
+		zpci_dbg(3, "rsv fid:%x\n", zdev->fid);
+		fallthrough;
+	case ZPCI_FN_STATE_RESERVED:
+		if (zdev->has_resources)
+			zpci_cleanup_bus_resources(zdev);
+		zpci_bus_device_unregister(zdev);
+		zpci_destroy_iommu(zdev);
+		fallthrough;
+	default:
+		break;
+	}
+	zpci_dbg(3, "rem fid:%x\n", zdev->fid);
+	kfree_rcu(zdev, rcu);
+}
+
+int zpci_report_error(struct pci_dev *pdev,
+		      struct zpci_report_error_header *report)
+{
+	struct zpci_dev *zdev = to_zpci(pdev);
+
+	return sclp_pci_report(report, zdev->fh, zdev->fid);
+}
+EXPORT_SYMBOL(zpci_report_error);
+
+/**
+ * zpci_clear_error_state() - Clears the zPCI error state of the device
+ * @zdev: The zdev for which the zPCI error state should be reset
+ *
+ * Clear the zPCI error state of the device. If clearing the zPCI error state
+ * fails the device is left in the error state. In this case it may make sense
+ * to call zpci_io_perm_failure() on the associated pdev if it exists.
+ *
+ * Returns: 0 on success, -EIO otherwise
+ */
+int zpci_clear_error_state(struct zpci_dev *zdev)
+{
+	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_RESET_ERROR);
+	struct zpci_fib fib = {0};
+	u8 status;
+	int cc;
+
+	cc = zpci_mod_fc(req, &fib, &status);
+	if (cc) {
+		zpci_dbg(3, "ces fid:%x, cc:%d, status:%x\n", zdev->fid, cc, status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * zpci_reset_load_store_blocked() - Re-enables L/S from error state
+ * @zdev: The zdev for which to unblock load/store access
+ *
+ * Re-enables load/store access for a PCI function in the error state while
+ * keeping DMA blocked. In this state drivers can poke MMIO space to determine
+ * if error recovery is possible while catching any rogue DMA access from the
+ * device.
+ *
+ * Returns: 0 on success, -EIO otherwise
+ */
+int zpci_reset_load_store_blocked(struct zpci_dev *zdev)
+{
+	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_RESET_BLOCK);
+	struct zpci_fib fib = {0};
+	u8 status;
+	int cc;
+
+	cc = zpci_mod_fc(req, &fib, &status);
+	if (cc) {
+		zpci_dbg(3, "rls fid:%x, cc:%d, status:%x\n", zdev->fid, cc, status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int zpci_mem_init(void)
+{
+	BUILD_BUG_ON(!is_power_of_2(__alignof__(struct zpci_fmb)) ||
+		     __alignof__(struct zpci_fmb) < sizeof(struct zpci_fmb));
+
+	zdev_fmb_cache = kmem_cache_create("PCI_FMB_cache", sizeof(struct zpci_fmb),
+					   __alignof__(struct zpci_fmb), 0, NULL);
+	if (!zdev_fmb_cache)
+		goto error_fmb;
+
+	zpci_iomap_start = kcalloc(ZPCI_IOMAP_ENTRIES,
+				   sizeof(*zpci_iomap_start), GFP_KERNEL);
+	if (!zpci_iomap_start)
+		goto error_iomap;
+
+	zpci_iomap_bitmap = kcalloc(BITS_TO_LONGS(ZPCI_IOMAP_ENTRIES),
+				    sizeof(*zpci_iomap_bitmap), GFP_KERNEL);
+	if (!zpci_iomap_bitmap)
+		goto error_iomap_bitmap;
+
+	if (static_branch_likely(&have_mio))
+		clp_setup_writeback_mio();
+
+	return 0;
+error_iomap_bitmap:
+	kfree(zpci_iomap_start);
+error_iomap:
+	kmem_cache_destroy(zdev_fmb_cache);
+error_fmb:
+	return -ENOMEM;
+}
+
+static void zpci_mem_exit(void)
+{
+	kfree(zpci_iomap_bitmap);
+	kfree(zpci_iomap_start);
+	kmem_cache_destroy(zdev_fmb_cache);
+}
+
+static unsigned int s390_pci_probe __initdata = 1;
+unsigned int s390_pci_force_floating __initdata;
+static unsigned int s390_pci_initialized;
+
+char * __init pcibios_setup(char *str)
+{
+	if (!strcmp(str, "off")) {
+		s390_pci_probe = 0;
+		return NULL;
+	}
+	if (!strcmp(str, "nomio")) {
+		S390_lowcore.machine_flags &= ~MACHINE_FLAG_PCI_MIO;
+		return NULL;
+	}
+	if (!strcmp(str, "force_floating")) {
+		s390_pci_force_floating = 1;
+		return NULL;
+	}
+	if (!strcmp(str, "norid")) {
+		s390_pci_no_rid = 1;
+		return NULL;
+	}
+	return str;
+}
+
+bool zpci_is_enabled(void)
+{
+	return s390_pci_initialized;
+}
+
+static int __init pci_base_init(void)
+{
+	int rc;
+
+	if (!s390_pci_probe)
+		return 0;
+
+	if (!test_facility(69) || !test_facility(71)) {
+		pr_info("PCI is not supported because CPU facilities 69 or 71 are not available\n");
+		return 0;
+	}
+
+	if (MACHINE_HAS_PCI_MIO) {
+		static_branch_enable(&have_mio);
+		ctl_set_bit(2, 5);
+	}
+
+	rc = zpci_debug_init();
+	if (rc)
+		goto out;
+
+	rc = zpci_mem_init();
+	if (rc)
+		goto out_mem;
+
+	rc = zpci_irq_init();
+	if (rc)
+		goto out_irq;
+
+	rc = zpci_dma_init();
+	if (rc)
+		goto out_dma;
+
+	rc = clp_scan_pci_devices();
+	if (rc)
+		goto out_find;
+	zpci_bus_scan_busses();
+
+	s390_pci_initialized = 1;
+	return 0;
+
+out_find:
+	zpci_dma_exit();
+out_dma:
+	zpci_irq_exit();
+out_irq:
+	zpci_mem_exit();
+out_mem:
+	zpci_debug_exit();
+out:
+	return rc;
+}
+subsys_initcall_sync(pci_base_init);