1 files changed, 130 insertions, 170 deletions

diff --git a/arch/powerpc/sysdev/dart_iommu.c b/arch/powerpc/sysdev/dart_iommu.c
index bd968a43a48b..c0d10c149661 100644
--- a/arch/powerpc/sysdev/dart_iommu.c
+++ b/arch/powerpc/sysdev/dart_iommu.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * arch/powerpc/sysdev/dart_iommu.c
  *
@@ -10,21 +11,6 @@
  * Copyright (C) 2004 Olof Johansson <olof@lixom.net>, IBM Corporation
  *
  * Dynamic DMA mapping support, Apple U3, U4 & IBM CPC925 "DART" iommu.
- *
- *
- * 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 of the License, 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  */
 
 #include <linux/init.h>
@@ -38,8 +24,8 @@
 #include <linux/suspend.h>
 #include <linux/memblock.h>
 #include <linux/gfp.h>
+#include <linux/of_address.h>
 #include <asm/io.h>
-#include <asm/prom.h>
 #include <asm/iommu.h>
 #include <asm/pci-bridge.h>
 #include <asm/machdep.h>
@@ -48,16 +34,10 @@
 
 #include "dart.h"
 
-/* Physical base address and size of the DART table */
-unsigned long dart_tablebase; /* exported to htab_initialize */
+/* DART table address and size */
+static u32 *dart_tablebase;
 static unsigned long dart_tablesize;
 
-/* Virtual base address of the DART table */
-static u32 *dart_vbase;
-#ifdef CONFIG_PM
-static u32 *dart_copy;
-#endif
-
 /* Mapped base address for the dart */
 static unsigned int __iomem *dart;
 
@@ -151,6 +131,34 @@ wait_more:
 	spin_unlock_irqrestore(&invalidate_lock, flags);
 }
 
+static void dart_cache_sync(unsigned int *base, unsigned int count)
+{
+	/*
+	 * We add 1 to the number of entries to flush, following a
+	 * comment in Darwin indicating that the memory controller
+	 * can prefetch unmapped memory under some circumstances.
+	 */
+	unsigned long start = (unsigned long)base;
+	unsigned long end = start + (count + 1) * sizeof(unsigned int);
+	unsigned int tmp;
+
+	/* Perform a standard cache flush */
+	flush_dcache_range(start, end);
+
+	/*
+	 * Perform the sequence described in the CPC925 manual to
+	 * ensure all the data gets to a point the cache incoherent
+	 * DART hardware will see.
+	 */
+	asm volatile(" sync;"
+		     " isync;"
+		     " dcbf 0,%1;"
+		     " sync;"
+		     " isync;"
+		     " lwz %0,0(%1);"
+		     " isync" : "=r" (tmp) : "r" (end) : "memory");
+}
+
 static void dart_flush(struct iommu_table *tbl)
 {
 	mb();
@@ -163,15 +171,15 @@ static void dart_flush(struct iommu_table *tbl)
 static int dart_build(struct iommu_table *tbl, long index,
 		       long npages, unsigned long uaddr,
 		       enum dma_data_direction direction,
-		       struct dma_attrs *attrs)
+		       unsigned long attrs)
 {
-	unsigned int *dp;
+	unsigned int *dp, *orig_dp;
 	unsigned int rpn;
 	long l;
 
 	DBG("dart: build at: %lx, %lx, addr: %x\n", index, npages, uaddr);
 
-	dp = ((unsigned int*)tbl->it_base) + index;
+	orig_dp = dp = ((unsigned int*)tbl->it_base) + index;
 
 	/* On U3, all memory is contiguous, so we can move this
 	 * out of the loop.
@@ -184,11 +192,7 @@ static int dart_build(struct iommu_table *tbl, long index,
 
 		uaddr += DART_PAGE_SIZE;
 	}
-
-	/* make sure all updates have reached memory */
-	mb();
-	in_be32((unsigned __iomem *)dp);
-	mb();
+	dart_cache_sync(orig_dp, npages);
 
 	if (dart_is_u4) {
 		rpn = index;
@@ -203,7 +207,8 @@ static int dart_build(struct iommu_table *tbl, long index,
 
 static void dart_free(struct iommu_table *tbl, long index, long npages)
 {
-	unsigned int *dp;
+	unsigned int *dp, *orig_dp;
+	long orig_npages = npages;
 
 	/* We don't worry about flushing the TLB cache. The only drawback of
 	 * not doing it is that we won't catch buggy device drivers doing
@@ -212,57 +217,87 @@ static void dart_free(struct iommu_table *tbl, long index, long npages)
 
 	DBG("dart: free at: %lx, %lx\n", index, npages);
 
-	dp  = ((unsigned int *)tbl->it_base) + index;
+	orig_dp = dp  = ((unsigned int *)tbl->it_base) + index;
 
 	while (npages--)
 		*(dp++) = dart_emptyval;
-}
 
+	dart_cache_sync(orig_dp, orig_npages);
+}
 
-static int __init dart_init(struct device_node *dart_node)
+static void __init allocate_dart(void)
 {
-	unsigned int i;
-	unsigned long tmp, base, size;
-	struct resource r;
-
-	if (dart_tablebase == 0 || dart_tablesize == 0) {
-		printk(KERN_INFO "DART: table not allocated, using "
-		       "direct DMA\n");
-		return -ENODEV;
-	}
+	unsigned long tmp;
 
-	if (of_address_to_resource(dart_node, 0, &r))
-		panic("DART: can't get register base ! ");
+	/* 512 pages (2MB) is max DART tablesize. */
+	dart_tablesize = 1UL << 21;
 
-	/* Make sure nothing from the DART range remains in the CPU cache
-	 * from a previous mapping that existed before the kernel took
-	 * over
+	/*
+	 * 16MB (1 << 24) alignment. We allocate a full 16Mb chuck since we
+	 * will blow up an entire large page anyway in the kernel mapping.
 	 */
-	flush_dcache_phys_range(dart_tablebase,
-				dart_tablebase + dart_tablesize);
+	dart_tablebase = memblock_alloc_try_nid_raw(SZ_16M, SZ_16M,
+					MEMBLOCK_LOW_LIMIT, SZ_2G,
+					NUMA_NO_NODE);
+	if (!dart_tablebase)
+		panic("Failed to allocate 16MB below 2GB for DART table\n");
 
 	/* Allocate a spare page to map all invalid DART pages. We need to do
 	 * that to work around what looks like a problem with the HT bridge
 	 * prefetching into invalid pages and corrupting data
 	 */
-	tmp = memblock_alloc(DART_PAGE_SIZE, DART_PAGE_SIZE);
+	tmp = memblock_phys_alloc(DART_PAGE_SIZE, DART_PAGE_SIZE);
+	if (!tmp)
+		panic("DART: table allocation failed\n");
+
 	dart_emptyval = DARTMAP_VALID | ((tmp >> DART_PAGE_SHIFT) &
 					 DARTMAP_RPNMASK);
 
+	printk(KERN_INFO "DART table allocated at: %p\n", dart_tablebase);
+}
+
+static int __init dart_init(struct device_node *dart_node)
+{
+	unsigned int i;
+	unsigned long base, size;
+	struct resource r;
+
+	/* IOMMU disabled by the user ? bail out */
+	if (iommu_is_off)
+		return -ENODEV;
+
+	/*
+	 * Only use the DART if the machine has more than 1GB of RAM
+	 * or if requested with iommu=on on cmdline.
+	 *
+	 * 1GB of RAM is picked as limit because some default devices
+	 * (i.e. Airport Extreme) have 30 bit address range limits.
+	 */
+
+	if (!iommu_force_on && memblock_end_of_DRAM() <= 0x40000000ull)
+		return -ENODEV;
+
+	/* Get DART registers */
+	if (of_address_to_resource(dart_node, 0, &r))
+		panic("DART: can't get register base ! ");
+
 	/* Map in DART registers */
 	dart = ioremap(r.start, resource_size(&r));
 	if (dart == NULL)
 		panic("DART: Cannot map registers!");
 
-	/* Map in DART table */
-	dart_vbase = ioremap(__pa(dart_tablebase), dart_tablesize);
+	/* Allocate the DART and dummy page */
+	allocate_dart();
 
 	/* Fill initial table */
 	for (i = 0; i < dart_tablesize/4; i++)
-		dart_vbase[i] = dart_emptyval;
+		dart_tablebase[i] = dart_emptyval;
+
+	/* Push to memory */
+	dart_cache_sync(dart_tablebase, dart_tablesize / sizeof(u32));
 
 	/* Initialize DART with table base and enable it. */
-	base = dart_tablebase >> DART_PAGE_SHIFT;
+	base = ((unsigned long)dart_tablebase) >> DART_PAGE_SHIFT;
 	size = dart_tablesize >> DART_PAGE_SHIFT;
 	if (dart_is_u4) {
 		size &= DART_SIZE_U4_SIZE_MASK;
@@ -286,18 +321,27 @@ static int __init dart_init(struct device_node *dart_node)
 	return 0;
 }
 
+static struct iommu_table_ops iommu_dart_ops = {
+	.set = dart_build,
+	.clear = dart_free,
+	.flush = dart_flush,
+};
+
 static void iommu_table_dart_setup(void)
 {
 	iommu_table_dart.it_busno = 0;
 	iommu_table_dart.it_offset = 0;
 	/* it_size is in number of entries */
 	iommu_table_dart.it_size = dart_tablesize / sizeof(u32);
+	iommu_table_dart.it_page_shift = IOMMU_PAGE_SHIFT_4K;
 
 	/* Initialize the common IOMMU code */
-	iommu_table_dart.it_base = (unsigned long)dart_vbase;
+	iommu_table_dart.it_base = (unsigned long)dart_tablebase;
 	iommu_table_dart.it_index = 0;
 	iommu_table_dart.it_blocksize = 1;
-	iommu_init_table(&iommu_table_dart, -1);
+	iommu_table_dart.it_ops = &iommu_dart_ops;
+	if (!iommu_init_table(&iommu_table_dart, -1, 0, 0))
+		panic("Failed to initialize iommu table");
 
 	/* Reserve the last page of the DART to avoid possible prefetch
 	 * past the DART mapped area
@@ -305,22 +349,6 @@ static void iommu_table_dart_setup(void)
 	set_bit(iommu_table_dart.it_size - 1, iommu_table_dart.it_map);
 }
 
-static void dma_dev_setup_dart(struct device *dev)
-{
-	/* We only have one iommu table on the mac for now, which makes
-	 * things simple. Setup all PCI devices to point to this table
-	 */
-	if (get_dma_ops(dev) == &dma_direct_ops)
-		set_dma_offset(dev, DART_U4_BYPASS_BASE);
-	else
-		set_iommu_table_base(dev, &iommu_table_dart);
-}
-
-static void pci_dma_dev_setup_dart(struct pci_dev *dev)
-{
-	dma_dev_setup_dart(&dev->dev);
-}
-
 static void pci_dma_bus_setup_dart(struct pci_bus *bus)
 {
 	if (!iommu_table_dart_inited) {
@@ -344,31 +372,21 @@ static bool dart_device_on_pcie(struct device *dev)
 	return false;
 }
 
-static int dart_dma_set_mask(struct device *dev, u64 dma_mask)
+static void pci_dma_dev_setup_dart(struct pci_dev *dev)
 {
-	if (!dev->dma_mask || !dma_supported(dev, dma_mask))
-		return -EIO;
-
-	/* U4 supports a DART bypass, we use it for 64-bit capable
-	 * devices to improve performances. However, that only works
-	 * for devices connected to U4 own PCIe interface, not bridged
-	 * through hypertransport. We need the device to support at
-	 * least 40 bits of addresses.
-	 */
-	if (dart_device_on_pcie(dev) && dma_mask >= DMA_BIT_MASK(40)) {
-		dev_info(dev, "Using 64-bit DMA iommu bypass\n");
-		set_dma_ops(dev, &dma_direct_ops);
-	} else {
-		dev_info(dev, "Using 32-bit DMA via iommu\n");
-		set_dma_ops(dev, &dma_iommu_ops);
-	}
-	dma_dev_setup_dart(dev);
+	if (dart_is_u4 && dart_device_on_pcie(&dev->dev))
+		dev->dev.archdata.dma_offset = DART_U4_BYPASS_BASE;
+	set_iommu_table_base(&dev->dev, &iommu_table_dart);
+}
 
-	*dev->dma_mask = dma_mask;
-	return 0;
+static bool iommu_bypass_supported_dart(struct pci_dev *dev, u64 mask)
+{
+	return dart_is_u4 &&
+		dart_device_on_pcie(&dev->dev) &&
+		mask >= DMA_BIT_MASK(40);
 }
 
-void __init iommu_init_early_dart(void)
+void __init iommu_init_early_dart(struct pci_controller_ops *controller_ops)
 {
 	struct device_node *dn;
 
@@ -382,99 +400,41 @@ void __init iommu_init_early_dart(void)
 	}
 
 	/* Initialize the DART HW */
-	if (dart_init(dn) != 0)
-		goto bail;
-
-	/* Setup low level TCE operations for the core IOMMU code */
-	ppc_md.tce_build = dart_build;
-	ppc_md.tce_free  = dart_free;
-	ppc_md.tce_flush = dart_flush;
-
-	/* Setup bypass if supported */
-	if (dart_is_u4)
-		ppc_md.dma_set_mask = dart_dma_set_mask;
-
-	ppc_md.pci_dma_dev_setup = pci_dma_dev_setup_dart;
-	ppc_md.pci_dma_bus_setup = pci_dma_bus_setup_dart;
+	if (dart_init(dn) != 0) {
+		of_node_put(dn);
+		return;
+	}
+	/*
+	 * U4 supports a DART bypass, we use it for 64-bit capable devices to
+	 * improve performance.  However, that only works for devices connected
+	 * to the U4 own PCIe interface, not bridged through hypertransport.
+	 * We need the device to support at least 40 bits of addresses.
+	 */
+	controller_ops->dma_dev_setup = pci_dma_dev_setup_dart;
+	controller_ops->dma_bus_setup = pci_dma_bus_setup_dart;
+	controller_ops->iommu_bypass_supported = iommu_bypass_supported_dart;
 
 	/* Setup pci_dma ops */
 	set_pci_dma_ops(&dma_iommu_ops);
-	return;
-
- bail:
-	/* If init failed, use direct iommu and null setup functions */
-	ppc_md.pci_dma_dev_setup = NULL;
-	ppc_md.pci_dma_bus_setup = NULL;
-
-	/* Setup pci_dma ops */
-	set_pci_dma_ops(&dma_direct_ops);
+	of_node_put(dn);
 }
 
 #ifdef CONFIG_PM
-static void iommu_dart_save(void)
-{
-	memcpy(dart_copy, dart_vbase, 2*1024*1024);
-}
-
 static void iommu_dart_restore(void)
 {
-	memcpy(dart_vbase, dart_copy, 2*1024*1024);
+	dart_cache_sync(dart_tablebase, dart_tablesize / sizeof(u32));
 	dart_tlb_invalidate_all();
 }
 
 static int __init iommu_init_late_dart(void)
 {
-	unsigned long tbasepfn;
-	struct page *p;
-
-	/* if no dart table exists then we won't need to save it
-	 * and the area has also not been reserved */
 	if (!dart_tablebase)
 		return 0;
 
-	tbasepfn = __pa(dart_tablebase) >> PAGE_SHIFT;
-	register_nosave_region_late(tbasepfn,
-				    tbasepfn + ((1<<24) >> PAGE_SHIFT));
-
-	/* For suspend we need to copy the dart contents because
-	 * it is not part of the regular mapping (see above) and
-	 * thus not saved automatically. The memory for this copy
-	 * must be allocated early because we need 2 MB. */
-	p = alloc_pages(GFP_KERNEL, 21 - PAGE_SHIFT);
-	BUG_ON(!p);
-	dart_copy = page_address(p);
-
-	ppc_md.iommu_save = iommu_dart_save;
 	ppc_md.iommu_restore = iommu_dart_restore;
 
 	return 0;
 }
 
 late_initcall(iommu_init_late_dart);
-#endif
-
-void __init alloc_dart_table(void)
-{
-	/* Only reserve DART space if machine has more than 1GB of RAM
-	 * or if requested with iommu=on on cmdline.
-	 *
-	 * 1GB of RAM is picked as limit because some default devices
-	 * (i.e. Airport Extreme) have 30 bit address range limits.
-	 */
-
-	if (iommu_is_off)
-		return;
-
-	if (!iommu_force_on && memblock_end_of_DRAM() <= 0x40000000ull)
-		return;
-
-	/* 512 pages (2MB) is max DART tablesize. */
-	dart_tablesize = 1UL << 21;
-	/* 16MB (1 << 24) alignment. We allocate a full 16Mb chuck since we
-	 * will blow up an entire large page anyway in the kernel mapping
-	 */
-	dart_tablebase = (unsigned long)
-		__va(memblock_alloc_base(1UL<<24, 1UL<<24, 0x80000000L));
-
-	printk(KERN_INFO "DART table allocated at: %lx\n", dart_tablebase);
-}
+#endif /* CONFIG_PM */