1 files changed, 171 insertions, 0 deletions
diff --git a/drivers/parisc/iommu-helpers.h b/drivers/parisc/iommu-helpers.h
new file mode 100644
index 000000000000..38d9e1aba1d0
--- /dev/null
+++ b/drivers/parisc/iommu-helpers.h
@@ -0,0 +1,171 @@
+/**
+ * iommu_fill_pdir - Insert coalesced scatter/gather chunks into the I/O Pdir.
+ * @ioc: The I/O Controller.
+ * @startsg: The scatter/gather list of coalesced chunks.
+ * @nents: The number of entries in the scatter/gather list.
+ * @hint: The DMA Hint.
+ *
+ * This function inserts the coalesced scatter/gather list chunks into the
+ * I/O Controller's I/O Pdir.
+ */ 
+static inline unsigned int
+iommu_fill_pdir(struct ioc *ioc, struct scatterlist *startsg, int nents, 
+                unsigned long hint,
+                void (*iommu_io_pdir_entry)(u64 *, space_t, unsigned long,
+                                            unsigned long))
+{
+        struct scatterlist *dma_sg = startsg;   /* pointer to current DMA */
+        unsigned int n_mappings = 0;
+        unsigned long dma_offset = 0, dma_len = 0;
+        u64 *pdirp = NULL;
+        /* Horrible hack.  For efficiency's sake, dma_sg starts one 
+         * entry below the true start (it is immediately incremented
+         * in the loop) */
+         dma_sg--;
+        while (nents-- > 0) {
+                unsigned long vaddr;
+                long size;
+                DBG_RUN_SG(" %d : %08lx/%05x %08lx/%05x\n", nents,
+                           (unsigned long)sg_dma_address(startsg), cnt,
+                           sg_virt_addr(startsg), startsg->length
+                );
+                /*
+                ** Look for the start of a new DMA stream
+                */
+                
+                if (sg_dma_address(startsg) & PIDE_FLAG) {
+                        u32 pide = sg_dma_address(startsg) & ~PIDE_FLAG;
+                        BUG_ON(pdirp && (dma_len != sg_dma_len(dma_sg)));
+                        dma_sg++;
+                        dma_len = sg_dma_len(startsg);
+                        sg_dma_len(startsg) = 0;
+                        dma_offset = (unsigned long) pide & ~IOVP_MASK;
+                        n_mappings++;
+#if defined(ZX1_SUPPORT)
+                        /* Pluto IOMMU IO Virt Address is not zero based */
+                        sg_dma_address(dma_sg) = pide | ioc->ibase;
+#else
+                        /* SBA, ccio, and dino are zero based.
+                         * Trying to save a few CPU cycles for most users.
+                         */
+                        sg_dma_address(dma_sg) = pide;
+#endif
+                        pdirp = &(ioc->pdir_base[pide >> IOVP_SHIFT]);
+                        prefetchw(pdirp);
+                }
+                
+                BUG_ON(pdirp == NULL);
+                
+                vaddr = sg_virt_addr(startsg);
+                sg_dma_len(dma_sg) += startsg->length;
+                size = startsg->length + dma_offset;
+                dma_offset = 0;
+#ifdef IOMMU_MAP_STATS
+                ioc->msg_pages += startsg->length >> IOVP_SHIFT;
+#endif
+                do {
+                        iommu_io_pdir_entry(pdirp, KERNEL_SPACE, 
+                                            vaddr, hint);
+                        vaddr += IOVP_SIZE;
+                        size -= IOVP_SIZE;
+                        pdirp++;
+                } while(unlikely(size > 0));
+                startsg++;
+        }
+        return(n_mappings);
+}
+/*
+** First pass is to walk the SG list and determine where the breaks are
+** in the DMA stream. Allocates PDIR entries but does not fill them.
+** Returns the number of DMA chunks.
+**
+** Doing the fill separate from the coalescing/allocation keeps the
+** code simpler. Future enhancement could make one pass through
+** the sglist do both.
+*/
+static inline unsigned int
+iommu_coalesce_chunks(struct ioc *ioc, struct scatterlist *startsg, int nents,
+                      int (*iommu_alloc_range)(struct ioc *, size_t))
+{
+        struct scatterlist *contig_sg;     /* contig chunk head */
+        unsigned long dma_offset, dma_len; /* start/len of DMA stream */
+        unsigned int n_mappings = 0;
+        while (nents > 0) {
+                /*
+                ** Prepare for first/next DMA stream
+                */
+                contig_sg = startsg;
+                dma_len = startsg->length;
+                dma_offset = sg_virt_addr(startsg) & ~IOVP_MASK;
+                /* PARANOID: clear entries */
+                sg_dma_address(startsg) = 0;
+                sg_dma_len(startsg) = 0;
+                /*
+                ** This loop terminates one iteration "early" since
+                ** it's always looking one "ahead".
+                */
+                while(--nents > 0) {
+                        unsigned long prevstartsg_end, startsg_end;
+                        prevstartsg_end = sg_virt_addr(startsg) +
+                                startsg->length;
+                        startsg++;
+                        startsg_end = sg_virt_addr(startsg) + 
+                                startsg->length;
+                        /* PARANOID: clear entries */
+                        sg_dma_address(startsg) = 0;
+                        sg_dma_len(startsg) = 0;
+                        /*
+                        ** First make sure current dma stream won't
+                        ** exceed DMA_CHUNK_SIZE if we coalesce the
+                        ** next entry.
+                        */   
+                        if(unlikely(ROUNDUP(dma_len + dma_offset + startsg->length,
+                                            IOVP_SIZE) > DMA_CHUNK_SIZE))
+                                break;
+                        /*
+                        ** Next see if we can append the next chunk (i.e.
+                        ** it must end on one page and begin on another
+                        */
+                        if (unlikely(((prevstartsg_end | sg_virt_addr(startsg)) & ~PAGE_MASK) != 0))
+                                break;
+                        
+                        dma_len += startsg->length;
+                }
+                /*
+                ** End of DMA Stream
+                ** Terminate last VCONTIG block.
+                ** Allocate space for DMA stream.
+                */
+                sg_dma_len(contig_sg) = dma_len;
+                dma_len = ROUNDUP(dma_len + dma_offset, IOVP_SIZE);
+                sg_dma_address(contig_sg) =
+                        PIDE_FLAG 
+                        | (iommu_alloc_range(ioc, dma_len) << IOVP_SHIFT)
+                        | dma_offset;
+                n_mappings++;
+        }
+        return n_mappings;
+}

diff --git a/drivers/parisc/iommu-helpers.h b/drivers/parisc/iommu-helpers.h new file mode 100644 index 000000000000..38d9e1aba1d0 --- /dev/null +++ b/drivers/parisc/iommu-helpers.h
@@ -0,0 +1,171 @@
	1	/**
	2	* iommu_fill_pdir - Insert coalesced scatter/gather chunks into the I/O Pdir.
	3	* @ioc: The I/O Controller.
	4	* @startsg: The scatter/gather list of coalesced chunks.
	5	* @nents: The number of entries in the scatter/gather list.
	6	* @hint: The DMA Hint.
	7	*
	8	* This function inserts the coalesced scatter/gather list chunks into the
	9	* I/O Controller's I/O Pdir.
	10	*/
	11	static inline unsigned int
	12	iommu_fill_pdir(struct ioc ioc, struct scatterlist startsg, int nents,
	13	unsigned long hint,
	14	void (iommu_io_pdir_entry)(u64 , space_t, unsigned long,
	15	unsigned long))
	16	{
	17	struct scatterlist dma_sg = startsg; / pointer to current DMA */
	18	unsigned int n_mappings = 0;
	19	unsigned long dma_offset = 0, dma_len = 0;
	20	u64 *pdirp = NULL;
	21
	22	/* Horrible hack. For efficiency's sake, dma_sg starts one
	23	* entry below the true start (it is immediately incremented
	24	* in the loop) */
	25	dma_sg--;
	26
	27	while (nents-- > 0) {
	28	unsigned long vaddr;
	29	long size;
	30
	31	DBG_RUN_SG(" %d : %08lx/%05x %08lx/%05x\n", nents,
	32	(unsigned long)sg_dma_address(startsg), cnt,
	33	sg_virt_addr(startsg), startsg->length
	34	);
	35
	36
	37	/*
	38	** Look for the start of a new DMA stream
	39	*/
	40
	41	if (sg_dma_address(startsg) & PIDE_FLAG) {
	42	u32 pide = sg_dma_address(startsg) & ~PIDE_FLAG;
	43
	44	BUG_ON(pdirp && (dma_len != sg_dma_len(dma_sg)));
	45
	46	dma_sg++;
	47
	48	dma_len = sg_dma_len(startsg);
	49	sg_dma_len(startsg) = 0;
	50	dma_offset = (unsigned long) pide & ~IOVP_MASK;
	51	n_mappings++;
	52	#if defined(ZX1_SUPPORT)
	53	/* Pluto IOMMU IO Virt Address is not zero based */
	54	sg_dma_address(dma_sg) = pide \| ioc->ibase;
	55	#else
	56	/* SBA, ccio, and dino are zero based.
	57	* Trying to save a few CPU cycles for most users.
	58	*/
	59	sg_dma_address(dma_sg) = pide;
	60	#endif
	61	pdirp = &(ioc->pdir_base[pide >> IOVP_SHIFT]);
	62	prefetchw(pdirp);
	63	}
	64
	65	BUG_ON(pdirp == NULL);
	66
	67	vaddr = sg_virt_addr(startsg);
	68	sg_dma_len(dma_sg) += startsg->length;
	69	size = startsg->length + dma_offset;
	70	dma_offset = 0;
	71	#ifdef IOMMU_MAP_STATS
	72	ioc->msg_pages += startsg->length >> IOVP_SHIFT;
	73	#endif
	74	do {
	75	iommu_io_pdir_entry(pdirp, KERNEL_SPACE,
	76	vaddr, hint);
	77	vaddr += IOVP_SIZE;
	78	size -= IOVP_SIZE;
	79	pdirp++;
	80	} while(unlikely(size > 0));
	81	startsg++;
	82	}
	83	return(n_mappings);
	84	}
	85
	86
	87	/*
	88	** First pass is to walk the SG list and determine where the breaks are
	89	** in the DMA stream. Allocates PDIR entries but does not fill them.
	90	** Returns the number of DMA chunks.
	91	**
	92	** Doing the fill separate from the coalescing/allocation keeps the
	93	** code simpler. Future enhancement could make one pass through
	94	** the sglist do both.
	95	*/
	96
	97	static inline unsigned int
	98	iommu_coalesce_chunks(struct ioc ioc, struct scatterlist startsg, int nents,
	99	int (iommu_alloc_range)(struct ioc , size_t))
	100	{
	101	struct scatterlist contig_sg; / contig chunk head */
	102	unsigned long dma_offset, dma_len; /* start/len of DMA stream */
	103	unsigned int n_mappings = 0;
	104
	105	while (nents > 0) {
	106
	107	/*
	108	** Prepare for first/next DMA stream
	109	*/
	110	contig_sg = startsg;
	111	dma_len = startsg->length;
	112	dma_offset = sg_virt_addr(startsg) & ~IOVP_MASK;
	113
	114	/* PARANOID: clear entries */
	115	sg_dma_address(startsg) = 0;
	116	sg_dma_len(startsg) = 0;
	117
	118	/*
	119	** This loop terminates one iteration "early" since
	120	** it's always looking one "ahead".
	121	*/
	122	while(--nents > 0) {
	123	unsigned long prevstartsg_end, startsg_end;
	124
	125	prevstartsg_end = sg_virt_addr(startsg) +
	126	startsg->length;
	127
	128	startsg++;
	129	startsg_end = sg_virt_addr(startsg) +
	130	startsg->length;
	131
	132	/* PARANOID: clear entries */
	133	sg_dma_address(startsg) = 0;
	134	sg_dma_len(startsg) = 0;
	135
	136	/*
	137	** First make sure current dma stream won't
	138	** exceed DMA_CHUNK_SIZE if we coalesce the
	139	** next entry.
	140	*/
	141	if(unlikely(ROUNDUP(dma_len + dma_offset + startsg->length,
	142	IOVP_SIZE) > DMA_CHUNK_SIZE))
	143	break;
	144
	145	/*
	146	** Next see if we can append the next chunk (i.e.
	147	** it must end on one page and begin on another
	148	*/
	149	if (unlikely(((prevstartsg_end \| sg_virt_addr(startsg)) & ~PAGE_MASK) != 0))
	150	break;
	151
	152	dma_len += startsg->length;
	153	}
	154
	155	/*
	156	** End of DMA Stream
	157	** Terminate last VCONTIG block.
	158	** Allocate space for DMA stream.
	159	*/
	160	sg_dma_len(contig_sg) = dma_len;
	161	dma_len = ROUNDUP(dma_len + dma_offset, IOVP_SIZE);
	162	sg_dma_address(contig_sg) =
	163	PIDE_FLAG
	164	\| (iommu_alloc_range(ioc, dma_len) << IOVP_SHIFT)
	165	\| dma_offset;
	166	n_mappings++;
	167	}
	168
	169	return n_mappings;
	170	}
	171