s390/pci: base support

Add PCI support for s390, (only 64 bit mode is supported by hardware):
- PCI facility tests
- PCI instructions: pcilg, pcistg, pcistb, stpcifc, mpcifc, rpcit
- map readb/w/l/q and writeb/w/l/q to pcilg and pcistg instructions
- pci_iomap implementation
- memcpy_fromio/toio
- pci_root_ops using special pcilg/pcistg
- device, bus and domain allocation

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/Kbuild

@@ -6,3 +6,4 @@ obj-$(CONFIG_S390_HYPFS_FS)	+= hypfs/
 obj-$(CONFIG_APPLDATA_BASE)	+= appldata/
 obj-$(CONFIG_MATHEMU)		+= math-emu/
 obj-y				+= net/
+obj-$(CONFIG_PCI)		+= pci/

arch/s390/include/asm/io.h

@@ -9,9 +9,9 @@
 #ifndef _S390_IO_H
 #define _S390_IO_H
 
+#include <linux/kernel.h>
 #include <asm/page.h>
-
-#define IO_SPACE_LIMIT 0xffffffff
+#include <asm/pci_io.h>
 
 /*
  * Change virtual addresses to physical addresses and vv.
@@ -24,10 +24,11 @@ static inline unsigned long virt_to_phys(volatile void * address)
 		 "	lra	%0,0(%1)\n"
 		 "	jz	0f\n"
 		 "	la	%0,0\n"
-                 "0:"
+		 "0:"
 		 : "=a" (real_address) : "a" (address) : "cc");
-        return real_address;
+	return real_address;
 }
+#define virt_to_phys virt_to_phys
 
 static inline void * phys_to_virt(unsigned long address)
 {
@@ -42,4 +43,50 @@ void unxlate_dev_mem_ptr(unsigned long phys, void *addr);
  */
 #define xlate_dev_kmem_ptr(p)	p
 
+#define IO_SPACE_LIMIT 0
+
+#ifdef CONFIG_PCI
+
+#define ioremap_nocache(addr, size)	ioremap(addr, size)
+#define ioremap_wc			ioremap_nocache
+
+/* TODO: s390 cannot support io_remap_pfn_range... */
+#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) 	       \
+	remap_pfn_range(vma, vaddr, pfn, size, prot)
+
+static inline void __iomem *ioremap(unsigned long offset, unsigned long size)
+{
+	return (void __iomem *) offset;
+}
+
+static inline void iounmap(volatile void __iomem *addr)
+{
+}
+
+/*
+ * s390 needs a private implementation of pci_iomap since ioremap with its
+ * offset parameter isn't sufficient. That's because BAR spaces are not
+ * disjunctive on s390 so we need the bar parameter of pci_iomap to find
+ * the corresponding device and create the mapping cookie.
+ */
+#define pci_iomap pci_iomap
+#define pci_iounmap pci_iounmap
+
+#define memcpy_fromio(dst, src, count)	zpci_memcpy_fromio(dst, src, count)
+#define memcpy_toio(dst, src, count)	zpci_memcpy_toio(dst, src, count)
+#define memset_io(dst, val, count)	zpci_memset_io(dst, val, count)
+
+#define __raw_readb	zpci_read_u8
+#define __raw_readw	zpci_read_u16
+#define __raw_readl	zpci_read_u32
+#define __raw_readq	zpci_read_u64
+#define __raw_writeb	zpci_write_u8
+#define __raw_writew	zpci_write_u16
+#define __raw_writel	zpci_write_u32
+#define __raw_writeq	zpci_write_u64
+
+#endif /* CONFIG_PCI */
+
+#include <asm-generic/io.h>
+
 #endif

arch/s390/include/asm/pci.h

@@ -1,10 +1,84 @@
 #ifndef __ASM_S390_PCI_H
 #define __ASM_S390_PCI_H
 
-/* S/390 systems don't have a PCI bus. This file is just here because some stupid .c code
- * includes it even if CONFIG_PCI is not set.
- */
+/* must be set before including asm-generic/pci.h */
 #define PCI_DMA_BUS_IS_PHYS (0)
+/* must be set before including pci_clp.h */
+#define PCI_BAR_COUNT	6
 
-#endif /* __ASM_S390_PCI_H */
+#include <asm-generic/pci.h>
+#include <asm-generic/pci-dma-compat.h>
 
+#define PCIBIOS_MIN_IO		0x1000
+#define PCIBIOS_MIN_MEM		0x10000000
+
+#define pcibios_assign_all_busses()	(0)
+
+void __iomem *pci_iomap(struct pci_dev *, int, unsigned long);
+void pci_iounmap(struct pci_dev *, void __iomem *);
+int pci_domain_nr(struct pci_bus *);
+int pci_proc_domain(struct pci_bus *);
+
+#define ZPCI_BUS_NR			0	/* default bus number */
+#define ZPCI_DEVFN			0	/* default device number */
+
+/* PCI Function Controls */
+#define ZPCI_FC_FN_ENABLED		0x80
+#define ZPCI_FC_ERROR			0x40
+#define ZPCI_FC_BLOCKED			0x20
+#define ZPCI_FC_DMA_ENABLED		0x10
+
+enum zpci_state {
+	ZPCI_FN_STATE_RESERVED,
+	ZPCI_FN_STATE_STANDBY,
+	ZPCI_FN_STATE_CONFIGURED,
+	ZPCI_FN_STATE_ONLINE,
+	NR_ZPCI_FN_STATES,
+};
+
+struct zpci_bar_struct {
+	u32		val;		/* bar start & 3 flag bits */
+	u8		size;		/* order 2 exponent */
+	u16		map_idx;	/* index into bar mapping array */
+};
+
+/* Private data per function */
+struct zpci_dev {
+	struct pci_dev	*pdev;
+	struct pci_bus	*bus;
+	struct list_head entry;		/* list of all zpci_devices, needed for hotplug, etc. */
+
+	enum zpci_state state;
+	u32		fid;		/* function ID, used by sclp */
+	u32		fh;		/* function handle, used by insn's */
+	u16		pchid;		/* physical channel ID */
+	u8		pfgid;		/* function group ID */
+	u16		domain;
+
+	struct zpci_bar_struct bars[PCI_BAR_COUNT];
+
+	enum pci_bus_speed max_bus_speed;
+};
+
+static inline bool zdev_enabled(struct zpci_dev *zdev)
+{
+	return (zdev->fh & (1UL << 31)) ? true : false;
+}
+
+/* -----------------------------------------------------------------------------
+  Prototypes
+----------------------------------------------------------------------------- */
+/* Base stuff */
+struct zpci_dev *zpci_alloc_device(void);
+int zpci_create_device(struct zpci_dev *);
+int zpci_enable_device(struct zpci_dev *);
+void zpci_stop_device(struct zpci_dev *);
+void zpci_free_device(struct zpci_dev *);
+int zpci_scan_device(struct zpci_dev *);
+
+/* Helpers */
+struct zpci_dev *get_zdev(struct pci_dev *);
+struct zpci_dev *get_zdev_by_fid(u32);
+bool zpci_fid_present(u32);
+
+#endif