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-rw-r--r--kernel/arch/powerpc/platforms/cell/iommu.c1237
1 files changed, 1237 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/platforms/cell/iommu.c b/kernel/arch/powerpc/platforms/cell/iommu.c
new file mode 100644
index 000000000..21b502398
--- /dev/null
+++ b/kernel/arch/powerpc/platforms/cell/iommu.c
@@ -0,0 +1,1237 @@
+/*
+ * IOMMU implementation for Cell Broadband Processor Architecture
+ *
+ * (C) Copyright IBM Corporation 2006-2008
+ *
+ * Author: Jeremy Kerr <jk@ozlabs.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+#include <linux/memblock.h>
+
+#include <asm/prom.h>
+#include <asm/iommu.h>
+#include <asm/machdep.h>
+#include <asm/pci-bridge.h>
+#include <asm/udbg.h>
+#include <asm/firmware.h>
+#include <asm/cell-regs.h>
+
+#include "cell.h"
+#include "interrupt.h"
+
+/* Define CELL_IOMMU_REAL_UNMAP to actually unmap non-used pages
+ * instead of leaving them mapped to some dummy page. This can be
+ * enabled once the appropriate workarounds for spider bugs have
+ * been enabled
+ */
+#define CELL_IOMMU_REAL_UNMAP
+
+/* Define CELL_IOMMU_STRICT_PROTECTION to enforce protection of
+ * IO PTEs based on the transfer direction. That can be enabled
+ * once spider-net has been fixed to pass the correct direction
+ * to the DMA mapping functions
+ */
+#define CELL_IOMMU_STRICT_PROTECTION
+
+
+#define NR_IOMMUS 2
+
+/* IOC mmap registers */
+#define IOC_Reg_Size 0x2000
+
+#define IOC_IOPT_CacheInvd 0x908
+#define IOC_IOPT_CacheInvd_NE_Mask 0xffe0000000000000ul
+#define IOC_IOPT_CacheInvd_IOPTE_Mask 0x000003fffffffff8ul
+#define IOC_IOPT_CacheInvd_Busy 0x0000000000000001ul
+
+#define IOC_IOST_Origin 0x918
+#define IOC_IOST_Origin_E 0x8000000000000000ul
+#define IOC_IOST_Origin_HW 0x0000000000000800ul
+#define IOC_IOST_Origin_HL 0x0000000000000400ul
+
+#define IOC_IO_ExcpStat 0x920
+#define IOC_IO_ExcpStat_V 0x8000000000000000ul
+#define IOC_IO_ExcpStat_SPF_Mask 0x6000000000000000ul
+#define IOC_IO_ExcpStat_SPF_S 0x6000000000000000ul
+#define IOC_IO_ExcpStat_SPF_P 0x2000000000000000ul
+#define IOC_IO_ExcpStat_ADDR_Mask 0x00000007fffff000ul
+#define IOC_IO_ExcpStat_RW_Mask 0x0000000000000800ul
+#define IOC_IO_ExcpStat_IOID_Mask 0x00000000000007fful
+
+#define IOC_IO_ExcpMask 0x928
+#define IOC_IO_ExcpMask_SFE 0x4000000000000000ul
+#define IOC_IO_ExcpMask_PFE 0x2000000000000000ul
+
+#define IOC_IOCmd_Offset 0x1000
+
+#define IOC_IOCmd_Cfg 0xc00
+#define IOC_IOCmd_Cfg_TE 0x0000800000000000ul
+
+
+/* Segment table entries */
+#define IOSTE_V 0x8000000000000000ul /* valid */
+#define IOSTE_H 0x4000000000000000ul /* cache hint */
+#define IOSTE_PT_Base_RPN_Mask 0x3ffffffffffff000ul /* base RPN of IOPT */
+#define IOSTE_NPPT_Mask 0x0000000000000fe0ul /* no. pages in IOPT */
+#define IOSTE_PS_Mask 0x0000000000000007ul /* page size */
+#define IOSTE_PS_4K 0x0000000000000001ul /* - 4kB */
+#define IOSTE_PS_64K 0x0000000000000003ul /* - 64kB */
+#define IOSTE_PS_1M 0x0000000000000005ul /* - 1MB */
+#define IOSTE_PS_16M 0x0000000000000007ul /* - 16MB */
+
+
+/* IOMMU sizing */
+#define IO_SEGMENT_SHIFT 28
+#define IO_PAGENO_BITS(shift) (IO_SEGMENT_SHIFT - (shift))
+
+/* The high bit needs to be set on every DMA address */
+#define SPIDER_DMA_OFFSET 0x80000000ul
+
+struct iommu_window {
+ struct list_head list;
+ struct cbe_iommu *iommu;
+ unsigned long offset;
+ unsigned long size;
+ unsigned int ioid;
+ struct iommu_table table;
+};
+
+#define NAMESIZE 8
+struct cbe_iommu {
+ int nid;
+ char name[NAMESIZE];
+ void __iomem *xlate_regs;
+ void __iomem *cmd_regs;
+ unsigned long *stab;
+ unsigned long *ptab;
+ void *pad_page;
+ struct list_head windows;
+};
+
+/* Static array of iommus, one per node
+ * each contains a list of windows, keyed from dma_window property
+ * - on bus setup, look for a matching window, or create one
+ * - on dev setup, assign iommu_table ptr
+ */
+static struct cbe_iommu iommus[NR_IOMMUS];
+static int cbe_nr_iommus;
+
+static void invalidate_tce_cache(struct cbe_iommu *iommu, unsigned long *pte,
+ long n_ptes)
+{
+ u64 __iomem *reg;
+ u64 val;
+ long n;
+
+ reg = iommu->xlate_regs + IOC_IOPT_CacheInvd;
+
+ while (n_ptes > 0) {
+ /* we can invalidate up to 1 << 11 PTEs at once */
+ n = min(n_ptes, 1l << 11);
+ val = (((n /*- 1*/) << 53) & IOC_IOPT_CacheInvd_NE_Mask)
+ | (__pa(pte) & IOC_IOPT_CacheInvd_IOPTE_Mask)
+ | IOC_IOPT_CacheInvd_Busy;
+
+ out_be64(reg, val);
+ while (in_be64(reg) & IOC_IOPT_CacheInvd_Busy)
+ ;
+
+ n_ptes -= n;
+ pte += n;
+ }
+}
+
+static int tce_build_cell(struct iommu_table *tbl, long index, long npages,
+ unsigned long uaddr, enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ int i;
+ unsigned long *io_pte, base_pte;
+ struct iommu_window *window =
+ container_of(tbl, struct iommu_window, table);
+
+ /* implementing proper protection causes problems with the spidernet
+ * driver - check mapping directions later, but allow read & write by
+ * default for now.*/
+#ifdef CELL_IOMMU_STRICT_PROTECTION
+ /* to avoid referencing a global, we use a trick here to setup the
+ * protection bit. "prot" is setup to be 3 fields of 4 bits apprended
+ * together for each of the 3 supported direction values. It is then
+ * shifted left so that the fields matching the desired direction
+ * lands on the appropriate bits, and other bits are masked out.
+ */
+ const unsigned long prot = 0xc48;
+ base_pte =
+ ((prot << (52 + 4 * direction)) &
+ (CBE_IOPTE_PP_W | CBE_IOPTE_PP_R)) |
+ CBE_IOPTE_M | CBE_IOPTE_SO_RW |
+ (window->ioid & CBE_IOPTE_IOID_Mask);
+#else
+ base_pte = CBE_IOPTE_PP_W | CBE_IOPTE_PP_R | CBE_IOPTE_M |
+ CBE_IOPTE_SO_RW | (window->ioid & CBE_IOPTE_IOID_Mask);
+#endif
+ if (unlikely(dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs)))
+ base_pte &= ~CBE_IOPTE_SO_RW;
+
+ io_pte = (unsigned long *)tbl->it_base + (index - tbl->it_offset);
+
+ for (i = 0; i < npages; i++, uaddr += (1 << tbl->it_page_shift))
+ io_pte[i] = base_pte | (__pa(uaddr) & CBE_IOPTE_RPN_Mask);
+
+ mb();
+
+ invalidate_tce_cache(window->iommu, io_pte, npages);
+
+ pr_debug("tce_build_cell(index=%lx,n=%lx,dir=%d,base_pte=%lx)\n",
+ index, npages, direction, base_pte);
+ return 0;
+}
+
+static void tce_free_cell(struct iommu_table *tbl, long index, long npages)
+{
+
+ int i;
+ unsigned long *io_pte, pte;
+ struct iommu_window *window =
+ container_of(tbl, struct iommu_window, table);
+
+ pr_debug("tce_free_cell(index=%lx,n=%lx)\n", index, npages);
+
+#ifdef CELL_IOMMU_REAL_UNMAP
+ pte = 0;
+#else
+ /* spider bridge does PCI reads after freeing - insert a mapping
+ * to a scratch page instead of an invalid entry */
+ pte = CBE_IOPTE_PP_R | CBE_IOPTE_M | CBE_IOPTE_SO_RW |
+ __pa(window->iommu->pad_page) |
+ (window->ioid & CBE_IOPTE_IOID_Mask);
+#endif
+
+ io_pte = (unsigned long *)tbl->it_base + (index - tbl->it_offset);
+
+ for (i = 0; i < npages; i++)
+ io_pte[i] = pte;
+
+ mb();
+
+ invalidate_tce_cache(window->iommu, io_pte, npages);
+}
+
+static irqreturn_t ioc_interrupt(int irq, void *data)
+{
+ unsigned long stat, spf;
+ struct cbe_iommu *iommu = data;
+
+ stat = in_be64(iommu->xlate_regs + IOC_IO_ExcpStat);
+ spf = stat & IOC_IO_ExcpStat_SPF_Mask;
+
+ /* Might want to rate limit it */
+ printk(KERN_ERR "iommu: DMA exception 0x%016lx\n", stat);
+ printk(KERN_ERR " V=%d, SPF=[%c%c], RW=%s, IOID=0x%04x\n",
+ !!(stat & IOC_IO_ExcpStat_V),
+ (spf == IOC_IO_ExcpStat_SPF_S) ? 'S' : ' ',
+ (spf == IOC_IO_ExcpStat_SPF_P) ? 'P' : ' ',
+ (stat & IOC_IO_ExcpStat_RW_Mask) ? "Read" : "Write",
+ (unsigned int)(stat & IOC_IO_ExcpStat_IOID_Mask));
+ printk(KERN_ERR " page=0x%016lx\n",
+ stat & IOC_IO_ExcpStat_ADDR_Mask);
+
+ /* clear interrupt */
+ stat &= ~IOC_IO_ExcpStat_V;
+ out_be64(iommu->xlate_regs + IOC_IO_ExcpStat, stat);
+
+ return IRQ_HANDLED;
+}
+
+static int cell_iommu_find_ioc(int nid, unsigned long *base)
+{
+ struct device_node *np;
+ struct resource r;
+
+ *base = 0;
+
+ /* First look for new style /be nodes */
+ for_each_node_by_name(np, "ioc") {
+ if (of_node_to_nid(np) != nid)
+ continue;
+ if (of_address_to_resource(np, 0, &r)) {
+ printk(KERN_ERR "iommu: can't get address for %s\n",
+ np->full_name);
+ continue;
+ }
+ *base = r.start;
+ of_node_put(np);
+ return 0;
+ }
+
+ /* Ok, let's try the old way */
+ for_each_node_by_type(np, "cpu") {
+ const unsigned int *nidp;
+ const unsigned long *tmp;
+
+ nidp = of_get_property(np, "node-id", NULL);
+ if (nidp && *nidp == nid) {
+ tmp = of_get_property(np, "ioc-translation", NULL);
+ if (tmp) {
+ *base = *tmp;
+ of_node_put(np);
+ return 0;
+ }
+ }
+ }
+
+ return -ENODEV;
+}
+
+static void cell_iommu_setup_stab(struct cbe_iommu *iommu,
+ unsigned long dbase, unsigned long dsize,
+ unsigned long fbase, unsigned long fsize)
+{
+ struct page *page;
+ unsigned long segments, stab_size;
+
+ segments = max(dbase + dsize, fbase + fsize) >> IO_SEGMENT_SHIFT;
+
+ pr_debug("%s: iommu[%d]: segments: %lu\n",
+ __func__, iommu->nid, segments);
+
+ /* set up the segment table */
+ stab_size = segments * sizeof(unsigned long);
+ page = alloc_pages_node(iommu->nid, GFP_KERNEL, get_order(stab_size));
+ BUG_ON(!page);
+ iommu->stab = page_address(page);
+ memset(iommu->stab, 0, stab_size);
+}
+
+static unsigned long *cell_iommu_alloc_ptab(struct cbe_iommu *iommu,
+ unsigned long base, unsigned long size, unsigned long gap_base,
+ unsigned long gap_size, unsigned long page_shift)
+{
+ struct page *page;
+ int i;
+ unsigned long reg, segments, pages_per_segment, ptab_size,
+ n_pte_pages, start_seg, *ptab;
+
+ start_seg = base >> IO_SEGMENT_SHIFT;
+ segments = size >> IO_SEGMENT_SHIFT;
+ pages_per_segment = 1ull << IO_PAGENO_BITS(page_shift);
+ /* PTEs for each segment must start on a 4K bounday */
+ pages_per_segment = max(pages_per_segment,
+ (1 << 12) / sizeof(unsigned long));
+
+ ptab_size = segments * pages_per_segment * sizeof(unsigned long);
+ pr_debug("%s: iommu[%d]: ptab_size: %lu, order: %d\n", __func__,
+ iommu->nid, ptab_size, get_order(ptab_size));
+ page = alloc_pages_node(iommu->nid, GFP_KERNEL, get_order(ptab_size));
+ BUG_ON(!page);
+
+ ptab = page_address(page);
+ memset(ptab, 0, ptab_size);
+
+ /* number of 4K pages needed for a page table */
+ n_pte_pages = (pages_per_segment * sizeof(unsigned long)) >> 12;
+
+ pr_debug("%s: iommu[%d]: stab at %p, ptab at %p, n_pte_pages: %lu\n",
+ __func__, iommu->nid, iommu->stab, ptab,
+ n_pte_pages);
+
+ /* initialise the STEs */
+ reg = IOSTE_V | ((n_pte_pages - 1) << 5);
+
+ switch (page_shift) {
+ case 12: reg |= IOSTE_PS_4K; break;
+ case 16: reg |= IOSTE_PS_64K; break;
+ case 20: reg |= IOSTE_PS_1M; break;
+ case 24: reg |= IOSTE_PS_16M; break;
+ default: BUG();
+ }
+
+ gap_base = gap_base >> IO_SEGMENT_SHIFT;
+ gap_size = gap_size >> IO_SEGMENT_SHIFT;
+
+ pr_debug("Setting up IOMMU stab:\n");
+ for (i = start_seg; i < (start_seg + segments); i++) {
+ if (i >= gap_base && i < (gap_base + gap_size)) {
+ pr_debug("\toverlap at %d, skipping\n", i);
+ continue;
+ }
+ iommu->stab[i] = reg | (__pa(ptab) + (n_pte_pages << 12) *
+ (i - start_seg));
+ pr_debug("\t[%d] 0x%016lx\n", i, iommu->stab[i]);
+ }
+
+ return ptab;
+}
+
+static void cell_iommu_enable_hardware(struct cbe_iommu *iommu)
+{
+ int ret;
+ unsigned long reg, xlate_base;
+ unsigned int virq;
+
+ if (cell_iommu_find_ioc(iommu->nid, &xlate_base))
+ panic("%s: missing IOC register mappings for node %d\n",
+ __func__, iommu->nid);
+
+ iommu->xlate_regs = ioremap(xlate_base, IOC_Reg_Size);
+ iommu->cmd_regs = iommu->xlate_regs + IOC_IOCmd_Offset;
+
+ /* ensure that the STEs have updated */
+ mb();
+
+ /* setup interrupts for the iommu. */
+ reg = in_be64(iommu->xlate_regs + IOC_IO_ExcpStat);
+ out_be64(iommu->xlate_regs + IOC_IO_ExcpStat,
+ reg & ~IOC_IO_ExcpStat_V);
+ out_be64(iommu->xlate_regs + IOC_IO_ExcpMask,
+ IOC_IO_ExcpMask_PFE | IOC_IO_ExcpMask_SFE);
+
+ virq = irq_create_mapping(NULL,
+ IIC_IRQ_IOEX_ATI | (iommu->nid << IIC_IRQ_NODE_SHIFT));
+ BUG_ON(virq == NO_IRQ);
+
+ ret = request_irq(virq, ioc_interrupt, 0, iommu->name, iommu);
+ BUG_ON(ret);
+
+ /* set the IOC segment table origin register (and turn on the iommu) */
+ reg = IOC_IOST_Origin_E | __pa(iommu->stab) | IOC_IOST_Origin_HW;
+ out_be64(iommu->xlate_regs + IOC_IOST_Origin, reg);
+ in_be64(iommu->xlate_regs + IOC_IOST_Origin);
+
+ /* turn on IO translation */
+ reg = in_be64(iommu->cmd_regs + IOC_IOCmd_Cfg) | IOC_IOCmd_Cfg_TE;
+ out_be64(iommu->cmd_regs + IOC_IOCmd_Cfg, reg);
+}
+
+static void cell_iommu_setup_hardware(struct cbe_iommu *iommu,
+ unsigned long base, unsigned long size)
+{
+ cell_iommu_setup_stab(iommu, base, size, 0, 0);
+ iommu->ptab = cell_iommu_alloc_ptab(iommu, base, size, 0, 0,
+ IOMMU_PAGE_SHIFT_4K);
+ cell_iommu_enable_hardware(iommu);
+}
+
+#if 0/* Unused for now */
+static struct iommu_window *find_window(struct cbe_iommu *iommu,
+ unsigned long offset, unsigned long size)
+{
+ struct iommu_window *window;
+
+ /* todo: check for overlapping (but not equal) windows) */
+
+ list_for_each_entry(window, &(iommu->windows), list) {
+ if (window->offset == offset && window->size == size)
+ return window;
+ }
+
+ return NULL;
+}
+#endif
+
+static inline u32 cell_iommu_get_ioid(struct device_node *np)
+{
+ const u32 *ioid;
+
+ ioid = of_get_property(np, "ioid", NULL);
+ if (ioid == NULL) {
+ printk(KERN_WARNING "iommu: missing ioid for %s using 0\n",
+ np->full_name);
+ return 0;
+ }
+
+ return *ioid;
+}
+
+static struct iommu_window * __init
+cell_iommu_setup_window(struct cbe_iommu *iommu, struct device_node *np,
+ unsigned long offset, unsigned long size,
+ unsigned long pte_offset)
+{
+ struct iommu_window *window;
+ struct page *page;
+ u32 ioid;
+
+ ioid = cell_iommu_get_ioid(np);
+
+ window = kzalloc_node(sizeof(*window), GFP_KERNEL, iommu->nid);
+ BUG_ON(window == NULL);
+
+ window->offset = offset;
+ window->size = size;
+ window->ioid = ioid;
+ window->iommu = iommu;
+
+ window->table.it_blocksize = 16;
+ window->table.it_base = (unsigned long)iommu->ptab;
+ window->table.it_index = iommu->nid;
+ window->table.it_page_shift = IOMMU_PAGE_SHIFT_4K;
+ window->table.it_offset =
+ (offset >> window->table.it_page_shift) + pte_offset;
+ window->table.it_size = size >> window->table.it_page_shift;
+
+ iommu_init_table(&window->table, iommu->nid);
+
+ pr_debug("\tioid %d\n", window->ioid);
+ pr_debug("\tblocksize %ld\n", window->table.it_blocksize);
+ pr_debug("\tbase 0x%016lx\n", window->table.it_base);
+ pr_debug("\toffset 0x%lx\n", window->table.it_offset);
+ pr_debug("\tsize %ld\n", window->table.it_size);
+
+ list_add(&window->list, &iommu->windows);
+
+ if (offset != 0)
+ return window;
+
+ /* We need to map and reserve the first IOMMU page since it's used
+ * by the spider workaround. In theory, we only need to do that when
+ * running on spider but it doesn't really matter.
+ *
+ * This code also assumes that we have a window that starts at 0,
+ * which is the case on all spider based blades.
+ */
+ page = alloc_pages_node(iommu->nid, GFP_KERNEL, 0);
+ BUG_ON(!page);
+ iommu->pad_page = page_address(page);
+ clear_page(iommu->pad_page);
+
+ __set_bit(0, window->table.it_map);
+ tce_build_cell(&window->table, window->table.it_offset, 1,
+ (unsigned long)iommu->pad_page, DMA_TO_DEVICE, NULL);
+
+ return window;
+}
+
+static struct cbe_iommu *cell_iommu_for_node(int nid)
+{
+ int i;
+
+ for (i = 0; i < cbe_nr_iommus; i++)
+ if (iommus[i].nid == nid)
+ return &iommus[i];
+ return NULL;
+}
+
+static unsigned long cell_dma_direct_offset;
+
+static unsigned long dma_iommu_fixed_base;
+
+/* iommu_fixed_is_weak is set if booted with iommu_fixed=weak */
+static int iommu_fixed_is_weak;
+
+static struct iommu_table *cell_get_iommu_table(struct device *dev)
+{
+ struct iommu_window *window;
+ struct cbe_iommu *iommu;
+
+ /* Current implementation uses the first window available in that
+ * node's iommu. We -might- do something smarter later though it may
+ * never be necessary
+ */
+ iommu = cell_iommu_for_node(dev_to_node(dev));
+ if (iommu == NULL || list_empty(&iommu->windows)) {
+ dev_err(dev, "iommu: missing iommu for %s (node %d)\n",
+ of_node_full_name(dev->of_node), dev_to_node(dev));
+ return NULL;
+ }
+ window = list_entry(iommu->windows.next, struct iommu_window, list);
+
+ return &window->table;
+}
+
+/* A coherent allocation implies strong ordering */
+
+static void *dma_fixed_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flag,
+ struct dma_attrs *attrs)
+{
+ if (iommu_fixed_is_weak)
+ return iommu_alloc_coherent(dev, cell_get_iommu_table(dev),
+ size, dma_handle,
+ device_to_mask(dev), flag,
+ dev_to_node(dev));
+ else
+ return dma_direct_ops.alloc(dev, size, dma_handle, flag,
+ attrs);
+}
+
+static void dma_fixed_free_coherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_handle,
+ struct dma_attrs *attrs)
+{
+ if (iommu_fixed_is_weak)
+ iommu_free_coherent(cell_get_iommu_table(dev), size, vaddr,
+ dma_handle);
+ else
+ dma_direct_ops.free(dev, size, vaddr, dma_handle, attrs);
+}
+
+static dma_addr_t dma_fixed_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size,
+ enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ if (iommu_fixed_is_weak == dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs))
+ return dma_direct_ops.map_page(dev, page, offset, size,
+ direction, attrs);
+ else
+ return iommu_map_page(dev, cell_get_iommu_table(dev), page,
+ offset, size, device_to_mask(dev),
+ direction, attrs);
+}
+
+static void dma_fixed_unmap_page(struct device *dev, dma_addr_t dma_addr,
+ size_t size, enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ if (iommu_fixed_is_weak == dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs))
+ dma_direct_ops.unmap_page(dev, dma_addr, size, direction,
+ attrs);
+ else
+ iommu_unmap_page(cell_get_iommu_table(dev), dma_addr, size,
+ direction, attrs);
+}
+
+static int dma_fixed_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ if (iommu_fixed_is_weak == dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs))
+ return dma_direct_ops.map_sg(dev, sg, nents, direction, attrs);
+ else
+ return ppc_iommu_map_sg(dev, cell_get_iommu_table(dev), sg,
+ nents, device_to_mask(dev),
+ direction, attrs);
+}
+
+static void dma_fixed_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ if (iommu_fixed_is_weak == dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs))
+ dma_direct_ops.unmap_sg(dev, sg, nents, direction, attrs);
+ else
+ ppc_iommu_unmap_sg(cell_get_iommu_table(dev), sg, nents,
+ direction, attrs);
+}
+
+static int dma_fixed_dma_supported(struct device *dev, u64 mask)
+{
+ return mask == DMA_BIT_MASK(64);
+}
+
+static int dma_set_mask_and_switch(struct device *dev, u64 dma_mask);
+
+struct dma_map_ops dma_iommu_fixed_ops = {
+ .alloc = dma_fixed_alloc_coherent,
+ .free = dma_fixed_free_coherent,
+ .map_sg = dma_fixed_map_sg,
+ .unmap_sg = dma_fixed_unmap_sg,
+ .dma_supported = dma_fixed_dma_supported,
+ .set_dma_mask = dma_set_mask_and_switch,
+ .map_page = dma_fixed_map_page,
+ .unmap_page = dma_fixed_unmap_page,
+};
+
+static void cell_dma_dev_setup_fixed(struct device *dev);
+
+static void cell_dma_dev_setup(struct device *dev)
+{
+ /* Order is important here, these are not mutually exclusive */
+ if (get_dma_ops(dev) == &dma_iommu_fixed_ops)
+ cell_dma_dev_setup_fixed(dev);
+ else if (get_pci_dma_ops() == &dma_iommu_ops)
+ set_iommu_table_base(dev, cell_get_iommu_table(dev));
+ else if (get_pci_dma_ops() == &dma_direct_ops)
+ set_dma_offset(dev, cell_dma_direct_offset);
+ else
+ BUG();
+}
+
+static void cell_pci_dma_dev_setup(struct pci_dev *dev)
+{
+ cell_dma_dev_setup(&dev->dev);
+}
+
+static int cell_of_bus_notify(struct notifier_block *nb, unsigned long action,
+ void *data)
+{
+ struct device *dev = data;
+
+ /* We are only intereted in device addition */
+ if (action != BUS_NOTIFY_ADD_DEVICE)
+ return 0;
+
+ /* We use the PCI DMA ops */
+ dev->archdata.dma_ops = get_pci_dma_ops();
+
+ cell_dma_dev_setup(dev);
+
+ return 0;
+}
+
+static struct notifier_block cell_of_bus_notifier = {
+ .notifier_call = cell_of_bus_notify
+};
+
+static int __init cell_iommu_get_window(struct device_node *np,
+ unsigned long *base,
+ unsigned long *size)
+{
+ const __be32 *dma_window;
+ unsigned long index;
+
+ /* Use ibm,dma-window if available, else, hard code ! */
+ dma_window = of_get_property(np, "ibm,dma-window", NULL);
+ if (dma_window == NULL) {
+ *base = 0;
+ *size = 0x80000000u;
+ return -ENODEV;
+ }
+
+ of_parse_dma_window(np, dma_window, &index, base, size);
+ return 0;
+}
+
+static struct cbe_iommu * __init cell_iommu_alloc(struct device_node *np)
+{
+ struct cbe_iommu *iommu;
+ int nid, i;
+
+ /* Get node ID */
+ nid = of_node_to_nid(np);
+ if (nid < 0) {
+ printk(KERN_ERR "iommu: failed to get node for %s\n",
+ np->full_name);
+ return NULL;
+ }
+ pr_debug("iommu: setting up iommu for node %d (%s)\n",
+ nid, np->full_name);
+
+ /* XXX todo: If we can have multiple windows on the same IOMMU, which
+ * isn't the case today, we probably want here to check whether the
+ * iommu for that node is already setup.
+ * However, there might be issue with getting the size right so let's
+ * ignore that for now. We might want to completely get rid of the
+ * multiple window support since the cell iommu supports per-page ioids
+ */
+
+ if (cbe_nr_iommus >= NR_IOMMUS) {
+ printk(KERN_ERR "iommu: too many IOMMUs detected ! (%s)\n",
+ np->full_name);
+ return NULL;
+ }
+
+ /* Init base fields */
+ i = cbe_nr_iommus++;
+ iommu = &iommus[i];
+ iommu->stab = NULL;
+ iommu->nid = nid;
+ snprintf(iommu->name, sizeof(iommu->name), "iommu%d", i);
+ INIT_LIST_HEAD(&iommu->windows);
+
+ return iommu;
+}
+
+static void __init cell_iommu_init_one(struct device_node *np,
+ unsigned long offset)
+{
+ struct cbe_iommu *iommu;
+ unsigned long base, size;
+
+ iommu = cell_iommu_alloc(np);
+ if (!iommu)
+ return;
+
+ /* Obtain a window for it */
+ cell_iommu_get_window(np, &base, &size);
+
+ pr_debug("\ttranslating window 0x%lx...0x%lx\n",
+ base, base + size - 1);
+
+ /* Initialize the hardware */
+ cell_iommu_setup_hardware(iommu, base, size);
+
+ /* Setup the iommu_table */
+ cell_iommu_setup_window(iommu, np, base, size,
+ offset >> IOMMU_PAGE_SHIFT_4K);
+}
+
+static void __init cell_disable_iommus(void)
+{
+ int node;
+ unsigned long base, val;
+ void __iomem *xregs, *cregs;
+
+ /* Make sure IOC translation is disabled on all nodes */
+ for_each_online_node(node) {
+ if (cell_iommu_find_ioc(node, &base))
+ continue;
+ xregs = ioremap(base, IOC_Reg_Size);
+ if (xregs == NULL)
+ continue;
+ cregs = xregs + IOC_IOCmd_Offset;
+
+ pr_debug("iommu: cleaning up iommu on node %d\n", node);
+
+ out_be64(xregs + IOC_IOST_Origin, 0);
+ (void)in_be64(xregs + IOC_IOST_Origin);
+ val = in_be64(cregs + IOC_IOCmd_Cfg);
+ val &= ~IOC_IOCmd_Cfg_TE;
+ out_be64(cregs + IOC_IOCmd_Cfg, val);
+ (void)in_be64(cregs + IOC_IOCmd_Cfg);
+
+ iounmap(xregs);
+ }
+}
+
+static int __init cell_iommu_init_disabled(void)
+{
+ struct device_node *np = NULL;
+ unsigned long base = 0, size;
+
+ /* When no iommu is present, we use direct DMA ops */
+ set_pci_dma_ops(&dma_direct_ops);
+
+ /* First make sure all IOC translation is turned off */
+ cell_disable_iommus();
+
+ /* If we have no Axon, we set up the spider DMA magic offset */
+ if (of_find_node_by_name(NULL, "axon") == NULL)
+ cell_dma_direct_offset = SPIDER_DMA_OFFSET;
+
+ /* Now we need to check to see where the memory is mapped
+ * in PCI space. We assume that all busses use the same dma
+ * window which is always the case so far on Cell, thus we
+ * pick up the first pci-internal node we can find and check
+ * the DMA window from there.
+ */
+ for_each_node_by_name(np, "axon") {
+ if (np->parent == NULL || np->parent->parent != NULL)
+ continue;
+ if (cell_iommu_get_window(np, &base, &size) == 0)
+ break;
+ }
+ if (np == NULL) {
+ for_each_node_by_name(np, "pci-internal") {
+ if (np->parent == NULL || np->parent->parent != NULL)
+ continue;
+ if (cell_iommu_get_window(np, &base, &size) == 0)
+ break;
+ }
+ }
+ of_node_put(np);
+
+ /* If we found a DMA window, we check if it's big enough to enclose
+ * all of physical memory. If not, we force enable IOMMU
+ */
+ if (np && size < memblock_end_of_DRAM()) {
+ printk(KERN_WARNING "iommu: force-enabled, dma window"
+ " (%ldMB) smaller than total memory (%lldMB)\n",
+ size >> 20, memblock_end_of_DRAM() >> 20);
+ return -ENODEV;
+ }
+
+ cell_dma_direct_offset += base;
+
+ if (cell_dma_direct_offset != 0)
+ cell_pci_controller_ops.dma_dev_setup = cell_pci_dma_dev_setup;
+
+ printk("iommu: disabled, direct DMA offset is 0x%lx\n",
+ cell_dma_direct_offset);
+
+ return 0;
+}
+
+/*
+ * Fixed IOMMU mapping support
+ *
+ * This code adds support for setting up a fixed IOMMU mapping on certain
+ * cell machines. For 64-bit devices this avoids the performance overhead of
+ * mapping and unmapping pages at runtime. 32-bit devices are unable to use
+ * the fixed mapping.
+ *
+ * The fixed mapping is established at boot, and maps all of physical memory
+ * 1:1 into device space at some offset. On machines with < 30 GB of memory
+ * we setup the fixed mapping immediately above the normal IOMMU window.
+ *
+ * For example a machine with 4GB of memory would end up with the normal
+ * IOMMU window from 0-2GB and the fixed mapping window from 2GB to 6GB. In
+ * this case a 64-bit device wishing to DMA to 1GB would be told to DMA to
+ * 3GB, plus any offset required by firmware. The firmware offset is encoded
+ * in the "dma-ranges" property.
+ *
+ * On machines with 30GB or more of memory, we are unable to place the fixed
+ * mapping above the normal IOMMU window as we would run out of address space.
+ * Instead we move the normal IOMMU window to coincide with the hash page
+ * table, this region does not need to be part of the fixed mapping as no
+ * device should ever be DMA'ing to it. We then setup the fixed mapping
+ * from 0 to 32GB.
+ */
+
+static u64 cell_iommu_get_fixed_address(struct device *dev)
+{
+ u64 cpu_addr, size, best_size, dev_addr = OF_BAD_ADDR;
+ struct device_node *np;
+ const u32 *ranges = NULL;
+ int i, len, best, naddr, nsize, pna, range_size;
+
+ np = of_node_get(dev->of_node);
+ while (1) {
+ naddr = of_n_addr_cells(np);
+ nsize = of_n_size_cells(np);
+ np = of_get_next_parent(np);
+ if (!np)
+ break;
+
+ ranges = of_get_property(np, "dma-ranges", &len);
+
+ /* Ignore empty ranges, they imply no translation required */
+ if (ranges && len > 0)
+ break;
+ }
+
+ if (!ranges) {
+ dev_dbg(dev, "iommu: no dma-ranges found\n");
+ goto out;
+ }
+
+ len /= sizeof(u32);
+
+ pna = of_n_addr_cells(np);
+ range_size = naddr + nsize + pna;
+
+ /* dma-ranges format:
+ * child addr : naddr cells
+ * parent addr : pna cells
+ * size : nsize cells
+ */
+ for (i = 0, best = -1, best_size = 0; i < len; i += range_size) {
+ cpu_addr = of_translate_dma_address(np, ranges + i + naddr);
+ size = of_read_number(ranges + i + naddr + pna, nsize);
+
+ if (cpu_addr == 0 && size > best_size) {
+ best = i;
+ best_size = size;
+ }
+ }
+
+ if (best >= 0) {
+ dev_addr = of_read_number(ranges + best, naddr);
+ } else
+ dev_dbg(dev, "iommu: no suitable range found!\n");
+
+out:
+ of_node_put(np);
+
+ return dev_addr;
+}
+
+static int dma_set_mask_and_switch(struct device *dev, u64 dma_mask)
+{
+ if (!dev->dma_mask || !dma_supported(dev, dma_mask))
+ return -EIO;
+
+ if (dma_mask == DMA_BIT_MASK(64) &&
+ cell_iommu_get_fixed_address(dev) != OF_BAD_ADDR)
+ {
+ dev_dbg(dev, "iommu: 64-bit OK, using fixed ops\n");
+ set_dma_ops(dev, &dma_iommu_fixed_ops);
+ } else {
+ dev_dbg(dev, "iommu: not 64-bit, using default ops\n");
+ set_dma_ops(dev, get_pci_dma_ops());
+ }
+
+ cell_dma_dev_setup(dev);
+
+ *dev->dma_mask = dma_mask;
+
+ return 0;
+}
+
+static void cell_dma_dev_setup_fixed(struct device *dev)
+{
+ u64 addr;
+
+ addr = cell_iommu_get_fixed_address(dev) + dma_iommu_fixed_base;
+ set_dma_offset(dev, addr);
+
+ dev_dbg(dev, "iommu: fixed addr = %llx\n", addr);
+}
+
+static void insert_16M_pte(unsigned long addr, unsigned long *ptab,
+ unsigned long base_pte)
+{
+ unsigned long segment, offset;
+
+ segment = addr >> IO_SEGMENT_SHIFT;
+ offset = (addr >> 24) - (segment << IO_PAGENO_BITS(24));
+ ptab = ptab + (segment * (1 << 12) / sizeof(unsigned long));
+
+ pr_debug("iommu: addr %lx ptab %p segment %lx offset %lx\n",
+ addr, ptab, segment, offset);
+
+ ptab[offset] = base_pte | (__pa(addr) & CBE_IOPTE_RPN_Mask);
+}
+
+static void cell_iommu_setup_fixed_ptab(struct cbe_iommu *iommu,
+ struct device_node *np, unsigned long dbase, unsigned long dsize,
+ unsigned long fbase, unsigned long fsize)
+{
+ unsigned long base_pte, uaddr, ioaddr, *ptab;
+
+ ptab = cell_iommu_alloc_ptab(iommu, fbase, fsize, dbase, dsize, 24);
+
+ dma_iommu_fixed_base = fbase;
+
+ pr_debug("iommu: mapping 0x%lx pages from 0x%lx\n", fsize, fbase);
+
+ base_pte = CBE_IOPTE_PP_W | CBE_IOPTE_PP_R | CBE_IOPTE_M |
+ (cell_iommu_get_ioid(np) & CBE_IOPTE_IOID_Mask);
+
+ if (iommu_fixed_is_weak)
+ pr_info("IOMMU: Using weak ordering for fixed mapping\n");
+ else {
+ pr_info("IOMMU: Using strong ordering for fixed mapping\n");
+ base_pte |= CBE_IOPTE_SO_RW;
+ }
+
+ for (uaddr = 0; uaddr < fsize; uaddr += (1 << 24)) {
+ /* Don't touch the dynamic region */
+ ioaddr = uaddr + fbase;
+ if (ioaddr >= dbase && ioaddr < (dbase + dsize)) {
+ pr_debug("iommu: fixed/dynamic overlap, skipping\n");
+ continue;
+ }
+
+ insert_16M_pte(uaddr, ptab, base_pte);
+ }
+
+ mb();
+}
+
+static int __init cell_iommu_fixed_mapping_init(void)
+{
+ unsigned long dbase, dsize, fbase, fsize, hbase, hend;
+ struct cbe_iommu *iommu;
+ struct device_node *np;
+
+ /* The fixed mapping is only supported on axon machines */
+ np = of_find_node_by_name(NULL, "axon");
+ of_node_put(np);
+
+ if (!np) {
+ pr_debug("iommu: fixed mapping disabled, no axons found\n");
+ return -1;
+ }
+
+ /* We must have dma-ranges properties for fixed mapping to work */
+ np = of_find_node_with_property(NULL, "dma-ranges");
+ of_node_put(np);
+
+ if (!np) {
+ pr_debug("iommu: no dma-ranges found, no fixed mapping\n");
+ return -1;
+ }
+
+ /* The default setup is to have the fixed mapping sit after the
+ * dynamic region, so find the top of the largest IOMMU window
+ * on any axon, then add the size of RAM and that's our max value.
+ * If that is > 32GB we have to do other shennanigans.
+ */
+ fbase = 0;
+ for_each_node_by_name(np, "axon") {
+ cell_iommu_get_window(np, &dbase, &dsize);
+ fbase = max(fbase, dbase + dsize);
+ }
+
+ fbase = _ALIGN_UP(fbase, 1 << IO_SEGMENT_SHIFT);
+ fsize = memblock_phys_mem_size();
+
+ if ((fbase + fsize) <= 0x800000000ul)
+ hbase = 0; /* use the device tree window */
+ else {
+ /* If we're over 32 GB we need to cheat. We can't map all of
+ * RAM with the fixed mapping, and also fit the dynamic
+ * region. So try to place the dynamic region where the hash
+ * table sits, drivers never need to DMA to it, we don't
+ * need a fixed mapping for that area.
+ */
+ if (!htab_address) {
+ pr_debug("iommu: htab is NULL, on LPAR? Huh?\n");
+ return -1;
+ }
+ hbase = __pa(htab_address);
+ hend = hbase + htab_size_bytes;
+
+ /* The window must start and end on a segment boundary */
+ if ((hbase != _ALIGN_UP(hbase, 1 << IO_SEGMENT_SHIFT)) ||
+ (hend != _ALIGN_UP(hend, 1 << IO_SEGMENT_SHIFT))) {
+ pr_debug("iommu: hash window not segment aligned\n");
+ return -1;
+ }
+
+ /* Check the hash window fits inside the real DMA window */
+ for_each_node_by_name(np, "axon") {
+ cell_iommu_get_window(np, &dbase, &dsize);
+
+ if (hbase < dbase || (hend > (dbase + dsize))) {
+ pr_debug("iommu: hash window doesn't fit in"
+ "real DMA window\n");
+ return -1;
+ }
+ }
+
+ fbase = 0;
+ }
+
+ /* Setup the dynamic regions */
+ for_each_node_by_name(np, "axon") {
+ iommu = cell_iommu_alloc(np);
+ BUG_ON(!iommu);
+
+ if (hbase == 0)
+ cell_iommu_get_window(np, &dbase, &dsize);
+ else {
+ dbase = hbase;
+ dsize = htab_size_bytes;
+ }
+
+ printk(KERN_DEBUG "iommu: node %d, dynamic window 0x%lx-0x%lx "
+ "fixed window 0x%lx-0x%lx\n", iommu->nid, dbase,
+ dbase + dsize, fbase, fbase + fsize);
+
+ cell_iommu_setup_stab(iommu, dbase, dsize, fbase, fsize);
+ iommu->ptab = cell_iommu_alloc_ptab(iommu, dbase, dsize, 0, 0,
+ IOMMU_PAGE_SHIFT_4K);
+ cell_iommu_setup_fixed_ptab(iommu, np, dbase, dsize,
+ fbase, fsize);
+ cell_iommu_enable_hardware(iommu);
+ cell_iommu_setup_window(iommu, np, dbase, dsize, 0);
+ }
+
+ dma_iommu_ops.set_dma_mask = dma_set_mask_and_switch;
+ set_pci_dma_ops(&dma_iommu_ops);
+
+ return 0;
+}
+
+static int iommu_fixed_disabled;
+
+static int __init setup_iommu_fixed(char *str)
+{
+ struct device_node *pciep;
+
+ if (strcmp(str, "off") == 0)
+ iommu_fixed_disabled = 1;
+
+ /* If we can find a pcie-endpoint in the device tree assume that
+ * we're on a triblade or a CAB so by default the fixed mapping
+ * should be set to be weakly ordered; but only if the boot
+ * option WASN'T set for strong ordering
+ */
+ pciep = of_find_node_by_type(NULL, "pcie-endpoint");
+
+ if (strcmp(str, "weak") == 0 || (pciep && strcmp(str, "strong") != 0))
+ iommu_fixed_is_weak = 1;
+
+ of_node_put(pciep);
+
+ return 1;
+}
+__setup("iommu_fixed=", setup_iommu_fixed);
+
+static u64 cell_dma_get_required_mask(struct device *dev)
+{
+ struct dma_map_ops *dma_ops;
+
+ if (!dev->dma_mask)
+ return 0;
+
+ if (!iommu_fixed_disabled &&
+ cell_iommu_get_fixed_address(dev) != OF_BAD_ADDR)
+ return DMA_BIT_MASK(64);
+
+ dma_ops = get_dma_ops(dev);
+ if (dma_ops->get_required_mask)
+ return dma_ops->get_required_mask(dev);
+
+ WARN_ONCE(1, "no get_required_mask in %p ops", dma_ops);
+
+ return DMA_BIT_MASK(64);
+}
+
+static int __init cell_iommu_init(void)
+{
+ struct device_node *np;
+
+ /* If IOMMU is disabled or we have little enough RAM to not need
+ * to enable it, we setup a direct mapping.
+ *
+ * Note: should we make sure we have the IOMMU actually disabled ?
+ */
+ if (iommu_is_off ||
+ (!iommu_force_on && memblock_end_of_DRAM() <= 0x80000000ull))
+ if (cell_iommu_init_disabled() == 0)
+ goto bail;
+
+ /* Setup various callbacks */
+ cell_pci_controller_ops.dma_dev_setup = cell_pci_dma_dev_setup;
+ ppc_md.dma_get_required_mask = cell_dma_get_required_mask;
+ ppc_md.tce_build = tce_build_cell;
+ ppc_md.tce_free = tce_free_cell;
+
+ if (!iommu_fixed_disabled && cell_iommu_fixed_mapping_init() == 0)
+ goto bail;
+
+ /* Create an iommu for each /axon node. */
+ for_each_node_by_name(np, "axon") {
+ if (np->parent == NULL || np->parent->parent != NULL)
+ continue;
+ cell_iommu_init_one(np, 0);
+ }
+
+ /* Create an iommu for each toplevel /pci-internal node for
+ * old hardware/firmware
+ */
+ for_each_node_by_name(np, "pci-internal") {
+ if (np->parent == NULL || np->parent->parent != NULL)
+ continue;
+ cell_iommu_init_one(np, SPIDER_DMA_OFFSET);
+ }
+
+ /* Setup default PCI iommu ops */
+ set_pci_dma_ops(&dma_iommu_ops);
+
+ bail:
+ /* Register callbacks on OF platform device addition/removal
+ * to handle linking them to the right DMA operations
+ */
+ bus_register_notifier(&platform_bus_type, &cell_of_bus_notifier);
+
+ return 0;
+}
+machine_arch_initcall(cell, cell_iommu_init);