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Diffstat (limited to 'arch/powerpc/platforms/powernv/pci-ioda-tce.c')
-rw-r--r--arch/powerpc/platforms/powernv/pci-ioda-tce.c427
1 files changed, 427 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/pci-ioda-tce.c b/arch/powerpc/platforms/powernv/pci-ioda-tce.c
new file mode 100644
index 000000000..5218f5da2
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/pci-ioda-tce.c
@@ -0,0 +1,427 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * TCE helpers for IODA PCI/PCIe on PowerNV platforms
+ *
+ * Copyright 2018 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/iommu.h>
+
+#include <asm/iommu.h>
+#include <asm/tce.h>
+#include "pci.h"
+
+unsigned long pnv_ioda_parse_tce_sizes(struct pnv_phb *phb)
+{
+ struct pci_controller *hose = phb->hose;
+ struct device_node *dn = hose->dn;
+ unsigned long mask = 0;
+ int i, rc, count;
+ u32 val;
+
+ count = of_property_count_u32_elems(dn, "ibm,supported-tce-sizes");
+ if (count <= 0) {
+ mask = SZ_4K | SZ_64K;
+ /* Add 16M for POWER8 by default */
+ if (cpu_has_feature(CPU_FTR_ARCH_207S) &&
+ !cpu_has_feature(CPU_FTR_ARCH_300))
+ mask |= SZ_16M | SZ_256M;
+ return mask;
+ }
+
+ for (i = 0; i < count; i++) {
+ rc = of_property_read_u32_index(dn, "ibm,supported-tce-sizes",
+ i, &val);
+ if (rc == 0)
+ mask |= 1ULL << val;
+ }
+
+ return mask;
+}
+
+void pnv_pci_setup_iommu_table(struct iommu_table *tbl,
+ void *tce_mem, u64 tce_size,
+ u64 dma_offset, unsigned int page_shift)
+{
+ tbl->it_blocksize = 16;
+ tbl->it_base = (unsigned long)tce_mem;
+ tbl->it_page_shift = page_shift;
+ tbl->it_offset = dma_offset >> tbl->it_page_shift;
+ tbl->it_index = 0;
+ tbl->it_size = tce_size >> 3;
+ tbl->it_busno = 0;
+ tbl->it_type = TCE_PCI;
+}
+
+static __be64 *pnv_alloc_tce_level(int nid, unsigned int shift)
+{
+ struct page *tce_mem = NULL;
+ __be64 *addr;
+
+ tce_mem = alloc_pages_node(nid, GFP_ATOMIC | __GFP_NOWARN,
+ shift - PAGE_SHIFT);
+ if (!tce_mem) {
+ pr_err("Failed to allocate a TCE memory, level shift=%d\n",
+ shift);
+ return NULL;
+ }
+ addr = page_address(tce_mem);
+ memset(addr, 0, 1UL << shift);
+
+ return addr;
+}
+
+static void pnv_pci_ioda2_table_do_free_pages(__be64 *addr,
+ unsigned long size, unsigned int levels);
+
+static __be64 *pnv_tce(struct iommu_table *tbl, bool user, long idx, bool alloc)
+{
+ __be64 *tmp = user ? tbl->it_userspace : (__be64 *) tbl->it_base;
+ int level = tbl->it_indirect_levels;
+ const long shift = ilog2(tbl->it_level_size);
+ unsigned long mask = (tbl->it_level_size - 1) << (level * shift);
+
+ while (level) {
+ int n = (idx & mask) >> (level * shift);
+ unsigned long oldtce, tce = be64_to_cpu(READ_ONCE(tmp[n]));
+
+ if (!tce) {
+ __be64 *tmp2;
+
+ if (!alloc)
+ return NULL;
+
+ tmp2 = pnv_alloc_tce_level(tbl->it_nid,
+ ilog2(tbl->it_level_size) + 3);
+ if (!tmp2)
+ return NULL;
+
+ tce = __pa(tmp2) | TCE_PCI_READ | TCE_PCI_WRITE;
+ oldtce = be64_to_cpu(cmpxchg(&tmp[n], 0,
+ cpu_to_be64(tce)));
+ if (oldtce) {
+ pnv_pci_ioda2_table_do_free_pages(tmp2,
+ ilog2(tbl->it_level_size) + 3, 1);
+ tce = oldtce;
+ }
+ }
+
+ tmp = __va(tce & ~(TCE_PCI_READ | TCE_PCI_WRITE));
+ idx &= ~mask;
+ mask >>= shift;
+ --level;
+ }
+
+ return tmp + idx;
+}
+
+int pnv_tce_build(struct iommu_table *tbl, long index, long npages,
+ unsigned long uaddr, enum dma_data_direction direction,
+ unsigned long attrs)
+{
+ u64 proto_tce = iommu_direction_to_tce_perm(direction);
+ u64 rpn = __pa(uaddr) >> tbl->it_page_shift;
+ long i;
+
+ if (proto_tce & TCE_PCI_WRITE)
+ proto_tce |= TCE_PCI_READ;
+
+ for (i = 0; i < npages; i++) {
+ unsigned long newtce = proto_tce |
+ ((rpn + i) << tbl->it_page_shift);
+ unsigned long idx = index - tbl->it_offset + i;
+
+ *(pnv_tce(tbl, false, idx, true)) = cpu_to_be64(newtce);
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_IOMMU_API
+int pnv_tce_xchg(struct iommu_table *tbl, long index,
+ unsigned long *hpa, enum dma_data_direction *direction,
+ bool alloc)
+{
+ u64 proto_tce = iommu_direction_to_tce_perm(*direction);
+ unsigned long newtce = *hpa | proto_tce, oldtce;
+ unsigned long idx = index - tbl->it_offset;
+ __be64 *ptce = NULL;
+
+ BUG_ON(*hpa & ~IOMMU_PAGE_MASK(tbl));
+
+ if (*direction == DMA_NONE) {
+ ptce = pnv_tce(tbl, false, idx, false);
+ if (!ptce) {
+ *hpa = 0;
+ return 0;
+ }
+ }
+
+ if (!ptce) {
+ ptce = pnv_tce(tbl, false, idx, alloc);
+ if (!ptce)
+ return -ENOMEM;
+ }
+
+ if (newtce & TCE_PCI_WRITE)
+ newtce |= TCE_PCI_READ;
+
+ oldtce = be64_to_cpu(xchg(ptce, cpu_to_be64(newtce)));
+ *hpa = oldtce & ~(TCE_PCI_READ | TCE_PCI_WRITE);
+ *direction = iommu_tce_direction(oldtce);
+
+ return 0;
+}
+
+__be64 *pnv_tce_useraddrptr(struct iommu_table *tbl, long index, bool alloc)
+{
+ if (WARN_ON_ONCE(!tbl->it_userspace))
+ return NULL;
+
+ return pnv_tce(tbl, true, index - tbl->it_offset, alloc);
+}
+#endif
+
+void pnv_tce_free(struct iommu_table *tbl, long index, long npages)
+{
+ long i;
+
+ for (i = 0; i < npages; i++) {
+ unsigned long idx = index - tbl->it_offset + i;
+ __be64 *ptce = pnv_tce(tbl, false, idx, false);
+
+ if (ptce)
+ *ptce = cpu_to_be64(0);
+ else
+ /* Skip the rest of the level */
+ i |= tbl->it_level_size - 1;
+ }
+}
+
+unsigned long pnv_tce_get(struct iommu_table *tbl, long index)
+{
+ __be64 *ptce = pnv_tce(tbl, false, index - tbl->it_offset, false);
+
+ if (!ptce)
+ return 0;
+
+ return be64_to_cpu(*ptce);
+}
+
+static void pnv_pci_ioda2_table_do_free_pages(__be64 *addr,
+ unsigned long size, unsigned int levels)
+{
+ const unsigned long addr_ul = (unsigned long) addr &
+ ~(TCE_PCI_READ | TCE_PCI_WRITE);
+
+ if (levels) {
+ long i;
+ u64 *tmp = (u64 *) addr_ul;
+
+ for (i = 0; i < size; ++i) {
+ unsigned long hpa = be64_to_cpu(tmp[i]);
+
+ if (!(hpa & (TCE_PCI_READ | TCE_PCI_WRITE)))
+ continue;
+
+ pnv_pci_ioda2_table_do_free_pages(__va(hpa), size,
+ levels - 1);
+ }
+ }
+
+ free_pages(addr_ul, get_order(size << 3));
+}
+
+void pnv_pci_ioda2_table_free_pages(struct iommu_table *tbl)
+{
+ const unsigned long size = tbl->it_indirect_levels ?
+ tbl->it_level_size : tbl->it_size;
+
+ if (!tbl->it_size)
+ return;
+
+ pnv_pci_ioda2_table_do_free_pages((__be64 *)tbl->it_base, size,
+ tbl->it_indirect_levels);
+ if (tbl->it_userspace) {
+ pnv_pci_ioda2_table_do_free_pages(tbl->it_userspace, size,
+ tbl->it_indirect_levels);
+ }
+}
+
+static __be64 *pnv_pci_ioda2_table_do_alloc_pages(int nid, unsigned int shift,
+ unsigned int levels, unsigned long limit,
+ unsigned long *current_offset, unsigned long *total_allocated)
+{
+ __be64 *addr, *tmp;
+ unsigned long allocated = 1UL << shift;
+ unsigned int entries = 1UL << (shift - 3);
+ long i;
+
+ addr = pnv_alloc_tce_level(nid, shift);
+ *total_allocated += allocated;
+
+ --levels;
+ if (!levels) {
+ *current_offset += allocated;
+ return addr;
+ }
+
+ for (i = 0; i < entries; ++i) {
+ tmp = pnv_pci_ioda2_table_do_alloc_pages(nid, shift,
+ levels, limit, current_offset, total_allocated);
+ if (!tmp)
+ break;
+
+ addr[i] = cpu_to_be64(__pa(tmp) |
+ TCE_PCI_READ | TCE_PCI_WRITE);
+
+ if (*current_offset >= limit)
+ break;
+ }
+
+ return addr;
+}
+
+long pnv_pci_ioda2_table_alloc_pages(int nid, __u64 bus_offset,
+ __u32 page_shift, __u64 window_size, __u32 levels,
+ bool alloc_userspace_copy, struct iommu_table *tbl)
+{
+ void *addr, *uas = NULL;
+ unsigned long offset = 0, level_shift, total_allocated = 0;
+ unsigned long total_allocated_uas = 0;
+ const unsigned int window_shift = ilog2(window_size);
+ unsigned int entries_shift = window_shift - page_shift;
+ unsigned int table_shift = max_t(unsigned int, entries_shift + 3,
+ PAGE_SHIFT);
+ const unsigned long tce_table_size = 1UL << table_shift;
+
+ if (!levels || (levels > POWERNV_IOMMU_MAX_LEVELS))
+ return -EINVAL;
+
+ if (!is_power_of_2(window_size))
+ return -EINVAL;
+
+ /* Adjust direct table size from window_size and levels */
+ entries_shift = (entries_shift + levels - 1) / levels;
+ level_shift = entries_shift + 3;
+ level_shift = max_t(unsigned int, level_shift, PAGE_SHIFT);
+
+ if ((level_shift - 3) * levels + page_shift >= 55)
+ return -EINVAL;
+
+ /* Allocate TCE table */
+ addr = pnv_pci_ioda2_table_do_alloc_pages(nid, level_shift,
+ 1, tce_table_size, &offset, &total_allocated);
+
+ /* addr==NULL means that the first level allocation failed */
+ if (!addr)
+ return -ENOMEM;
+
+ /*
+ * First level was allocated but some lower level failed as
+ * we did not allocate as much as we wanted,
+ * release partially allocated table.
+ */
+ if (levels == 1 && offset < tce_table_size)
+ goto free_tces_exit;
+
+ /* Allocate userspace view of the TCE table */
+ if (alloc_userspace_copy) {
+ offset = 0;
+ uas = pnv_pci_ioda2_table_do_alloc_pages(nid, level_shift,
+ 1, tce_table_size, &offset,
+ &total_allocated_uas);
+ if (!uas)
+ goto free_tces_exit;
+ if (levels == 1 && (offset < tce_table_size ||
+ total_allocated_uas != total_allocated))
+ goto free_uas_exit;
+ }
+
+ /* Setup linux iommu table */
+ pnv_pci_setup_iommu_table(tbl, addr, tce_table_size, bus_offset,
+ page_shift);
+ tbl->it_level_size = 1ULL << (level_shift - 3);
+ tbl->it_indirect_levels = levels - 1;
+ tbl->it_userspace = uas;
+ tbl->it_nid = nid;
+
+ pr_debug("Created TCE table: ws=%08llx ts=%lx @%08llx base=%lx uas=%p levels=%d/%d\n",
+ window_size, tce_table_size, bus_offset, tbl->it_base,
+ tbl->it_userspace, 1, levels);
+
+ return 0;
+
+free_uas_exit:
+ pnv_pci_ioda2_table_do_free_pages(uas,
+ 1ULL << (level_shift - 3), levels - 1);
+free_tces_exit:
+ pnv_pci_ioda2_table_do_free_pages(addr,
+ 1ULL << (level_shift - 3), levels - 1);
+
+ return -ENOMEM;
+}
+
+void pnv_pci_unlink_table_and_group(struct iommu_table *tbl,
+ struct iommu_table_group *table_group)
+{
+ long i;
+ bool found;
+ struct iommu_table_group_link *tgl;
+
+ if (!tbl || !table_group)
+ return;
+
+ /* Remove link to a group from table's list of attached groups */
+ found = false;
+ list_for_each_entry_rcu(tgl, &tbl->it_group_list, next) {
+ if (tgl->table_group == table_group) {
+ list_del_rcu(&tgl->next);
+ kfree_rcu(tgl, rcu);
+ found = true;
+ break;
+ }
+ }
+ if (WARN_ON(!found))
+ return;
+
+ /* Clean a pointer to iommu_table in iommu_table_group::tables[] */
+ found = false;
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
+ if (table_group->tables[i] == tbl) {
+ iommu_tce_table_put(tbl);
+ table_group->tables[i] = NULL;
+ found = true;
+ break;
+ }
+ }
+ WARN_ON(!found);
+}
+
+long pnv_pci_link_table_and_group(int node, int num,
+ struct iommu_table *tbl,
+ struct iommu_table_group *table_group)
+{
+ struct iommu_table_group_link *tgl = NULL;
+
+ if (WARN_ON(!tbl || !table_group))
+ return -EINVAL;
+
+ tgl = kzalloc_node(sizeof(struct iommu_table_group_link), GFP_KERNEL,
+ node);
+ if (!tgl)
+ return -ENOMEM;
+
+ tgl->table_group = table_group;
+ list_add_rcu(&tgl->next, &tbl->it_group_list);
+
+ table_group->tables[num] = iommu_tce_table_get(tbl);
+
+ return 0;
+}