// SPDX-License-Identifier: GPL-2.0-only /* * 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. */ #include <linux/pci.h> #include <linux/pci_ids.h> #include <linux/export.h> #include <linux/list.h> #include <linux/dma-direct.h> #include <asm/iommu.h> #define STA2X11_SWIOTLB_SIZE (4*1024*1024) /* * 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 { 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; } /* 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); /* 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; /* 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); /* * 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_instance *instance = sta2x11_pdev_to_instance(pdev); struct device *dev = &pdev->dev; u32 amba_base, max_amba_addr; int i, ret; if (!instance) return; pci_read_config_dword(pdev, AHB_BASE(0), &amba_base); max_amba_addr = amba_base + STA2X11_AMBA_SIZE - 1; ret = dma_direct_set_offset(dev, 0, amba_base, STA2X11_AMBA_SIZE); if (ret) dev_err(dev, "sta2x11: could not set DMA offset\n"); dev->bus_dma_limit = max_amba_addr; pci_set_consistent_dma_mask(pdev, max_amba_addr); pci_set_dma_mask(pdev, max_amba_addr); /* 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), amba_base, max_amba_addr); } 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 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; } 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 */