s390/pci: DMA support

Add DMA IOMMU support using 4K page table entries. Implement dma_map_ops.

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

1 files changed, 196 insertions, 0 deletions

diff --git a/arch/s390/include/asm/pci_dma.h b/arch/s390/include/asm/pci_dma.h
new file mode 100644
index 000000000000..30b4c179c38c
--- /dev/null
+++ b/arch/s390/include/asm/pci_dma.h
@@ -0,0 +1,196 @@
+#ifndef _ASM_S390_PCI_DMA_H
+#define _ASM_S390_PCI_DMA_H
+
+/* I/O Translation Anchor (IOTA) */
+enum zpci_ioat_dtype {
+	ZPCI_IOTA_STO = 0,
+	ZPCI_IOTA_RTTO = 1,
+	ZPCI_IOTA_RSTO = 2,
+	ZPCI_IOTA_RFTO = 3,
+	ZPCI_IOTA_PFAA = 4,
+	ZPCI_IOTA_IOPFAA = 5,
+	ZPCI_IOTA_IOPTO = 7
+};
+
+#define ZPCI_IOTA_IOT_ENABLED		0x800UL
+#define ZPCI_IOTA_DT_ST			(ZPCI_IOTA_STO	<< 2)
+#define ZPCI_IOTA_DT_RT			(ZPCI_IOTA_RTTO << 2)
+#define ZPCI_IOTA_DT_RS			(ZPCI_IOTA_RSTO << 2)
+#define ZPCI_IOTA_DT_RF			(ZPCI_IOTA_RFTO << 2)
+#define ZPCI_IOTA_DT_PF			(ZPCI_IOTA_PFAA << 2)
+#define ZPCI_IOTA_FS_4K			0
+#define ZPCI_IOTA_FS_1M			1
+#define ZPCI_IOTA_FS_2G			2
+#define ZPCI_KEY			(PAGE_DEFAULT_KEY << 5)
+
+#define ZPCI_IOTA_STO_FLAG	(ZPCI_IOTA_IOT_ENABLED | ZPCI_KEY | ZPCI_IOTA_DT_ST)
+#define ZPCI_IOTA_RTTO_FLAG	(ZPCI_IOTA_IOT_ENABLED | ZPCI_KEY | ZPCI_IOTA_DT_RT)
+#define ZPCI_IOTA_RSTO_FLAG	(ZPCI_IOTA_IOT_ENABLED | ZPCI_KEY | ZPCI_IOTA_DT_RS)
+#define ZPCI_IOTA_RFTO_FLAG	(ZPCI_IOTA_IOT_ENABLED | ZPCI_KEY | ZPCI_IOTA_DT_RF)
+#define ZPCI_IOTA_RFAA_FLAG	(ZPCI_IOTA_IOT_ENABLED | ZPCI_KEY | ZPCI_IOTA_DT_PF | ZPCI_IOTA_FS_2G)
+
+/* I/O Region and segment tables */
+#define ZPCI_INDEX_MASK			0x7ffUL
+
+#define ZPCI_TABLE_TYPE_MASK		0xc
+#define ZPCI_TABLE_TYPE_RFX		0xc
+#define ZPCI_TABLE_TYPE_RSX		0x8
+#define ZPCI_TABLE_TYPE_RTX		0x4
+#define ZPCI_TABLE_TYPE_SX		0x0
+
+#define ZPCI_TABLE_LEN_RFX		0x3
+#define ZPCI_TABLE_LEN_RSX		0x3
+#define ZPCI_TABLE_LEN_RTX		0x3
+
+#define ZPCI_TABLE_OFFSET_MASK		0xc0
+#define ZPCI_TABLE_SIZE			0x4000
+#define ZPCI_TABLE_ALIGN		ZPCI_TABLE_SIZE
+#define ZPCI_TABLE_ENTRY_SIZE		(sizeof(unsigned long))
+#define ZPCI_TABLE_ENTRIES		(ZPCI_TABLE_SIZE / ZPCI_TABLE_ENTRY_SIZE)
+
+#define ZPCI_TABLE_BITS			11
+#define ZPCI_PT_BITS			8
+#define ZPCI_ST_SHIFT			(ZPCI_PT_BITS + PAGE_SHIFT)
+#define ZPCI_RT_SHIFT			(ZPCI_ST_SHIFT + ZPCI_TABLE_BITS)
+
+#define ZPCI_RTE_FLAG_MASK		0x3fffUL
+#define ZPCI_RTE_ADDR_MASK		(~ZPCI_RTE_FLAG_MASK)
+#define ZPCI_STE_FLAG_MASK		0x7ffUL
+#define ZPCI_STE_ADDR_MASK		(~ZPCI_STE_FLAG_MASK)
+
+/* I/O Page tables */
+#define ZPCI_PTE_VALID_MASK		0x400
+#define ZPCI_PTE_INVALID		0x400
+#define ZPCI_PTE_VALID			0x000
+#define ZPCI_PT_SIZE			0x800
+#define ZPCI_PT_ALIGN			ZPCI_PT_SIZE
+#define ZPCI_PT_ENTRIES			(ZPCI_PT_SIZE / ZPCI_TABLE_ENTRY_SIZE)
+#define ZPCI_PT_MASK			(ZPCI_PT_ENTRIES - 1)
+
+#define ZPCI_PTE_FLAG_MASK		0xfffUL
+#define ZPCI_PTE_ADDR_MASK		(~ZPCI_PTE_FLAG_MASK)
+
+/* Shared bits */
+#define ZPCI_TABLE_VALID		0x00
+#define ZPCI_TABLE_INVALID		0x20
+#define ZPCI_TABLE_PROTECTED		0x200
+#define ZPCI_TABLE_UNPROTECTED		0x000
+
+#define ZPCI_TABLE_VALID_MASK		0x20
+#define ZPCI_TABLE_PROT_MASK		0x200
+
+static inline unsigned int calc_rtx(dma_addr_t ptr)
+{
+	return ((unsigned long) ptr >> ZPCI_RT_SHIFT) & ZPCI_INDEX_MASK;
+}
+
+static inline unsigned int calc_sx(dma_addr_t ptr)
+{
+	return ((unsigned long) ptr >> ZPCI_ST_SHIFT) & ZPCI_INDEX_MASK;
+}
+
+static inline unsigned int calc_px(dma_addr_t ptr)
+{
+	return ((unsigned long) ptr >> PAGE_SHIFT) & ZPCI_PT_MASK;
+}
+
+static inline void set_pt_pfaa(unsigned long *entry, void *pfaa)
+{
+	*entry &= ZPCI_PTE_FLAG_MASK;
+	*entry |= ((unsigned long) pfaa & ZPCI_PTE_ADDR_MASK);
+}
+
+static inline void set_rt_sto(unsigned long *entry, void *sto)
+{
+	*entry &= ZPCI_RTE_FLAG_MASK;
+	*entry |= ((unsigned long) sto & ZPCI_RTE_ADDR_MASK);
+	*entry |= ZPCI_TABLE_TYPE_RTX;
+}
+
+static inline void set_st_pto(unsigned long *entry, void *pto)
+{
+	*entry &= ZPCI_STE_FLAG_MASK;
+	*entry |= ((unsigned long) pto & ZPCI_STE_ADDR_MASK);
+	*entry |= ZPCI_TABLE_TYPE_SX;
+}
+
+static inline void validate_rt_entry(unsigned long *entry)
+{
+	*entry &= ~ZPCI_TABLE_VALID_MASK;
+	*entry &= ~ZPCI_TABLE_OFFSET_MASK;
+	*entry |= ZPCI_TABLE_VALID;
+	*entry |= ZPCI_TABLE_LEN_RTX;
+}
+
+static inline void validate_st_entry(unsigned long *entry)
+{
+	*entry &= ~ZPCI_TABLE_VALID_MASK;
+	*entry |= ZPCI_TABLE_VALID;
+}
+
+static inline void invalidate_table_entry(unsigned long *entry)
+{
+	*entry &= ~ZPCI_TABLE_VALID_MASK;
+	*entry |= ZPCI_TABLE_INVALID;
+}
+
+static inline void invalidate_pt_entry(unsigned long *entry)
+{
+	WARN_ON_ONCE((*entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_INVALID);
+	*entry &= ~ZPCI_PTE_VALID_MASK;
+	*entry |= ZPCI_PTE_INVALID;
+}
+
+static inline void validate_pt_entry(unsigned long *entry)
+{
+	WARN_ON_ONCE((*entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID);
+	*entry &= ~ZPCI_PTE_VALID_MASK;
+	*entry |= ZPCI_PTE_VALID;
+}
+
+static inline void entry_set_protected(unsigned long *entry)
+{
+	*entry &= ~ZPCI_TABLE_PROT_MASK;
+	*entry |= ZPCI_TABLE_PROTECTED;
+}
+
+static inline void entry_clr_protected(unsigned long *entry)
+{
+	*entry &= ~ZPCI_TABLE_PROT_MASK;
+	*entry |= ZPCI_TABLE_UNPROTECTED;
+}
+
+static inline int reg_entry_isvalid(unsigned long entry)
+{
+	return (entry & ZPCI_TABLE_VALID_MASK) == ZPCI_TABLE_VALID;
+}
+
+static inline int pt_entry_isvalid(unsigned long entry)
+{
+	return (entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID;
+}
+
+static inline int entry_isprotected(unsigned long entry)
+{
+	return (entry & ZPCI_TABLE_PROT_MASK) == ZPCI_TABLE_PROTECTED;
+}
+
+static inline unsigned long *get_rt_sto(unsigned long entry)
+{
+	return ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_RTX)
+		? (unsigned long *) (entry & ZPCI_RTE_ADDR_MASK)
+		: NULL;
+}
+
+static inline unsigned long *get_st_pto(unsigned long entry)
+{
+	return ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_SX)
+		? (unsigned long *) (entry & ZPCI_STE_ADDR_MASK)
+		: NULL;
+}
+
+/* Prototypes */
+int zpci_dma_init_device(struct zpci_dev *);
+void zpci_dma_exit_device(struct zpci_dev *);
+
+#endif