--- /dev/null
+/*
+ * arch/x86/pci/sta2x11-fixup.c
+ * glue code for lib/swiotlb.c and DMA translation between STA2x11
+ * AMBA memory mapping and the X86 memory mapping
+ *
+ * ST Microelectronics ConneXt (STA2X11/STA2X10)
+ *
+ * Copyright (c) 2010-2011 Wind River Systems, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/export.h>
+#include <linux/list.h>
+
+#define STA2X11_SWIOTLB_SIZE (4*1024*1024)
+extern int swiotlb_late_init_with_default_size(size_t default_size);
+
+/*
+ * We build a list of bus numbers that are under the ConneXt. The
+ * main bridge hosts 4 busses, which are the 4 endpoints, in order.
+ */
+#define STA2X11_NR_EP 4 /* 0..3 included */
+#define STA2X11_NR_FUNCS 8 /* 0..7 included */
+#define STA2X11_AMBA_SIZE (512 << 20)
+
+struct sta2x11_ahb_regs { /* saved during suspend */
+ u32 base, pexlbase, pexhbase, crw;
+};
+
+struct sta2x11_mapping {
+ u32 amba_base;
+ int is_suspended;
+ struct sta2x11_ahb_regs regs[STA2X11_NR_FUNCS];
+};
+
+struct sta2x11_instance {
+ struct list_head list;
+ int bus0;
+ struct sta2x11_mapping map[STA2X11_NR_EP];
+};
+
+static LIST_HEAD(sta2x11_instance_list);
+
+/* At probe time, record new instances of this bridge (likely one only) */
+static void sta2x11_new_instance(struct pci_dev *pdev)
+{
+ struct sta2x11_instance *instance;
+
+ instance = kzalloc(sizeof(*instance), GFP_ATOMIC);
+ if (!instance)
+ return;
+ /* This has a subordinate bridge, with 4 more-subordinate ones */
+ instance->bus0 = pdev->subordinate->number + 1;
+
+ if (list_empty(&sta2x11_instance_list)) {
+ int size = STA2X11_SWIOTLB_SIZE;
+ /* First instance: register your own swiotlb area */
+ dev_info(&pdev->dev, "Using SWIOTLB (size %i)\n", size);
+ if (swiotlb_late_init_with_default_size(size))
+ dev_emerg(&pdev->dev, "init swiotlb failed\n");
+ }
+ list_add(&instance->list, &sta2x11_instance_list);
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, 0xcc17, sta2x11_new_instance);
+
+/*
+ * Utility functions used in this file from below
+ */
+static struct sta2x11_instance *sta2x11_pdev_to_instance(struct pci_dev *pdev)
+{
+ struct sta2x11_instance *instance;
+ int ep;
+
+ list_for_each_entry(instance, &sta2x11_instance_list, list) {
+ ep = pdev->bus->number - instance->bus0;
+ if (ep >= 0 && ep < STA2X11_NR_EP)
+ return instance;
+ }
+ return NULL;
+}
+
+static int sta2x11_pdev_to_ep(struct pci_dev *pdev)
+{
+ struct sta2x11_instance *instance;
+
+ instance = sta2x11_pdev_to_instance(pdev);
+ if (!instance)
+ return -1;
+
+ return pdev->bus->number - instance->bus0;
+}
+
+static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev)
+{
+ struct sta2x11_instance *instance;
+ int ep;
+
+ instance = sta2x11_pdev_to_instance(pdev);
+ if (!instance)
+ return NULL;
+ ep = sta2x11_pdev_to_ep(pdev);
+ return instance->map + ep;
+}
+
+/* This is exported, as some devices need to access the MFD registers */
+struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev)
+{
+ return sta2x11_pdev_to_instance(pdev);
+}
+EXPORT_SYMBOL(sta2x11_get_instance);
+
+
+/**
+ * p2a - Translate physical address to STA2x11 AMBA address,
+ * used for DMA transfers to STA2x11
+ * @p: Physical address
+ * @pdev: PCI device (must be hosted within the connext)
+ */
+static dma_addr_t p2a(dma_addr_t p, struct pci_dev *pdev)
+{
+ struct sta2x11_mapping *map;
+ dma_addr_t a;
+
+ map = sta2x11_pdev_to_mapping(pdev);
+ a = p + map->amba_base;
+ return a;
+}
+
+/**
+ * a2p - Translate STA2x11 AMBA address to physical address
+ * used for DMA transfers from STA2x11
+ * @a: STA2x11 AMBA address
+ * @pdev: PCI device (must be hosted within the connext)
+ */
+static dma_addr_t a2p(dma_addr_t a, struct pci_dev *pdev)
+{
+ struct sta2x11_mapping *map;
+ dma_addr_t p;
+
+ map = sta2x11_pdev_to_mapping(pdev);
+ p = a - map->amba_base;
+ return p;
+}
+
+/**
+ * sta2x11_swiotlb_alloc_coherent - Allocate swiotlb bounce buffers
+ * returns virtual address. This is the only "special" function here.
+ * @dev: PCI device
+ * @size: Size of the buffer
+ * @dma_handle: DMA address
+ * @flags: memory flags
+ */
+static void *sta2x11_swiotlb_alloc_coherent(struct device *dev,
+ size_t size,
+ dma_addr_t *dma_handle,
+ gfp_t flags,
+ struct dma_attrs *attrs)
+{
+ void *vaddr;
+
+ vaddr = dma_generic_alloc_coherent(dev, size, dma_handle, flags, attrs);
+ if (!vaddr)
+ vaddr = swiotlb_alloc_coherent(dev, size, dma_handle, flags);
+ *dma_handle = p2a(*dma_handle, to_pci_dev(dev));
+ return vaddr;
+}
+
+/* We have our own dma_ops: the same as swiotlb but from alloc (above) */
+static struct dma_map_ops sta2x11_dma_ops = {
+ .alloc = sta2x11_swiotlb_alloc_coherent,
+ .free = swiotlb_free_coherent,
+ .map_page = swiotlb_map_page,
+ .unmap_page = swiotlb_unmap_page,
+ .map_sg = swiotlb_map_sg_attrs,
+ .unmap_sg = swiotlb_unmap_sg_attrs,
+ .sync_single_for_cpu = swiotlb_sync_single_for_cpu,
+ .sync_single_for_device = swiotlb_sync_single_for_device,
+ .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
+ .sync_sg_for_device = swiotlb_sync_sg_for_device,
+ .mapping_error = swiotlb_dma_mapping_error,
+ .dma_supported = NULL, /* FIXME: we should use this instead! */
+};
+
+/* At setup time, we use our own ops if the device is a ConneXt one */
+static void sta2x11_setup_pdev(struct pci_dev *pdev)
+{
+ struct sta2x11_instance *instance = sta2x11_pdev_to_instance(pdev);
+
+ if (!instance) /* either a sta2x11 bridge or another ST device */
+ return;
+ pci_set_consistent_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
+ pci_set_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
+ pdev->dev.archdata.dma_ops = &sta2x11_dma_ops;
+
+ /* We must enable all devices as master, for audio DMA to work */
+ pci_set_master(pdev);
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_setup_pdev);
+
+/*
+ * The following three functions are exported (used in swiotlb: FIXME)
+ */
+/**
+ * dma_capable - Check if device can manage DMA transfers (FIXME: kill it)
+ * @dev: device for a PCI device
+ * @addr: DMA address
+ * @size: DMA size
+ */
+bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
+{
+ struct sta2x11_mapping *map;
+
+ if (dev->archdata.dma_ops != &sta2x11_dma_ops) {
+ if (!dev->dma_mask)
+ return false;
+ return addr + size - 1 <= *dev->dma_mask;
+ }
+
+ map = sta2x11_pdev_to_mapping(to_pci_dev(dev));
+
+ if (!map || (addr < map->amba_base))
+ return false;
+ if (addr + size >= map->amba_base + STA2X11_AMBA_SIZE) {
+ return false;
+ }
+
+ return true;
+}
+
+/**
+ * phys_to_dma - Return the DMA AMBA address used for this STA2x11 device
+ * @dev: device for a PCI device
+ * @paddr: Physical address
+ */
+dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+{
+ if (dev->archdata.dma_ops != &sta2x11_dma_ops)
+ return paddr;
+ return p2a(paddr, to_pci_dev(dev));
+}
+
+/**
+ * dma_to_phys - Return the physical address used for this STA2x11 DMA address
+ * @dev: device for a PCI device
+ * @daddr: STA2x11 AMBA DMA address
+ */
+phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
+{
+ if (dev->archdata.dma_ops != &sta2x11_dma_ops)
+ return daddr;
+ return a2p(daddr, to_pci_dev(dev));
+}
+
+
+/*
+ * At boot we must set up the mappings for the pcie-to-amba bridge.
+ * It involves device access, and the same happens at suspend/resume time
+ */
+
+#define AHB_MAPB 0xCA4
+#define AHB_CRW(i) (AHB_MAPB + 0 + (i) * 0x10)
+#define AHB_CRW_SZMASK 0xfffffc00UL
+#define AHB_CRW_ENABLE (1 << 0)
+#define AHB_CRW_WTYPE_MEM (2 << 1)
+#define AHB_CRW_ROE (1UL << 3) /* Relax Order Ena */
+#define AHB_CRW_NSE (1UL << 4) /* No Snoop Enable */
+#define AHB_BASE(i) (AHB_MAPB + 4 + (i) * 0x10)
+#define AHB_PEXLBASE(i) (AHB_MAPB + 8 + (i) * 0x10)
+#define AHB_PEXHBASE(i) (AHB_MAPB + 12 + (i) * 0x10)
+
+/* At probe time, enable mapping for each endpoint, using the pdev */
+static void sta2x11_map_ep(struct pci_dev *pdev)
+{
+ struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+ int i;
+
+ if (!map)
+ return;
+ pci_read_config_dword(pdev, AHB_BASE(0), &map->amba_base);
+
+ /* Configure AHB mapping */
+ pci_write_config_dword(pdev, AHB_PEXLBASE(0), 0);
+ pci_write_config_dword(pdev, AHB_PEXHBASE(0), 0);
+ pci_write_config_dword(pdev, AHB_CRW(0), STA2X11_AMBA_SIZE |
+ AHB_CRW_WTYPE_MEM | AHB_CRW_ENABLE);
+
+ /* Disable all the other windows */
+ for (i = 1; i < STA2X11_NR_FUNCS; i++)
+ pci_write_config_dword(pdev, AHB_CRW(i), 0);
+
+ dev_info(&pdev->dev,
+ "sta2x11: Map EP %i: AMBA address %#8x-%#8x\n",
+ sta2x11_pdev_to_ep(pdev), map->amba_base,
+ map->amba_base + STA2X11_AMBA_SIZE - 1);
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_map_ep);
+
+#ifdef CONFIG_PM /* Some register values must be saved and restored */
+
+static void suspend_mapping(struct pci_dev *pdev)
+{
+ struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+ int i;
+
+ if (!map)
+ return;
+
+ if (map->is_suspended)
+ return;
+ map->is_suspended = 1;
+
+ /* Save all window configs */
+ for (i = 0; i < STA2X11_NR_FUNCS; i++) {
+ struct sta2x11_ahb_regs *regs = map->regs + i;
+
+ pci_read_config_dword(pdev, AHB_BASE(i), ®s->base);
+ pci_read_config_dword(pdev, AHB_PEXLBASE(i), ®s->pexlbase);
+ pci_read_config_dword(pdev, AHB_PEXHBASE(i), ®s->pexhbase);
+ pci_read_config_dword(pdev, AHB_CRW(i), ®s->crw);
+ }
+}
+DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, suspend_mapping);
+
+static void resume_mapping(struct pci_dev *pdev)
+{
+ struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+ int i;
+
+ if (!map)
+ return;
+
+
+ if (!map->is_suspended)
+ goto out;
+ map->is_suspended = 0;
+
+ /* Restore all window configs */
+ for (i = 0; i < STA2X11_NR_FUNCS; i++) {
+ struct sta2x11_ahb_regs *regs = map->regs + i;
+
+ pci_write_config_dword(pdev, AHB_BASE(i), regs->base);
+ pci_write_config_dword(pdev, AHB_PEXLBASE(i), regs->pexlbase);
+ pci_write_config_dword(pdev, AHB_PEXHBASE(i), regs->pexhbase);
+ pci_write_config_dword(pdev, AHB_CRW(i), regs->crw);
+ }
+out:
+ pci_set_master(pdev); /* Like at boot, enable master on all devices */
+}
+DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, resume_mapping);
+
+#endif /* CONFIG_PM */
projects / platform / kernel / linux-rpi.git / commitdiff