diff options
Diffstat (limited to 'drivers/pci/ide.c')
| -rw-r--r-- | drivers/pci/ide.c | 815 |
1 files changed, 815 insertions, 0 deletions
diff --git a/drivers/pci/ide.c b/drivers/pci/ide.c new file mode 100644 index 000000000000..f0ef474e1a0d --- /dev/null +++ b/drivers/pci/ide.c @@ -0,0 +1,815 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright(c) 2024-2025 Intel Corporation. All rights reserved. */ + +/* PCIe r7.0 section 6.33 Integrity & Data Encryption (IDE) */ + +#define dev_fmt(fmt) "PCI/IDE: " fmt +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/pci.h> +#include <linux/pci-ide.h> +#include <linux/pci_regs.h> +#include <linux/slab.h> +#include <linux/sysfs.h> +#include <linux/tsm.h> + +#include "pci.h" + +static int __sel_ide_offset(u16 ide_cap, u8 nr_link_ide, u8 stream_index, + u8 nr_ide_mem) +{ + u32 offset = ide_cap + PCI_IDE_LINK_STREAM_0 + + nr_link_ide * PCI_IDE_LINK_BLOCK_SIZE; + + /* + * Assume a constant number of address association resources per stream + * index + */ + return offset + stream_index * PCI_IDE_SEL_BLOCK_SIZE(nr_ide_mem); +} + +static int sel_ide_offset(struct pci_dev *pdev, + struct pci_ide_partner *settings) +{ + return __sel_ide_offset(pdev->ide_cap, pdev->nr_link_ide, + settings->stream_index, pdev->nr_ide_mem); +} + +static bool reserve_stream_index(struct pci_dev *pdev, u8 idx) +{ + int ret; + + ret = ida_alloc_range(&pdev->ide_stream_ida, idx, idx, GFP_KERNEL); + return ret >= 0; +} + +static bool reserve_stream_id(struct pci_host_bridge *hb, u8 id) +{ + int ret; + + ret = ida_alloc_range(&hb->ide_stream_ids_ida, id, id, GFP_KERNEL); + return ret >= 0; +} + +static bool claim_stream(struct pci_host_bridge *hb, u8 stream_id, + struct pci_dev *pdev, u8 stream_idx) +{ + dev_info(&hb->dev, "Stream ID %d active at init\n", stream_id); + if (!reserve_stream_id(hb, stream_id)) { + dev_info(&hb->dev, "Failed to claim %s Stream ID %d\n", + stream_id == PCI_IDE_RESERVED_STREAM_ID ? "reserved" : + "active", + stream_id); + return false; + } + + /* No stream index to reserve in the Link IDE case */ + if (!pdev) + return true; + + if (!reserve_stream_index(pdev, stream_idx)) { + pci_info(pdev, "Failed to claim active Selective Stream %d\n", + stream_idx); + return false; + } + + return true; +} + +void pci_ide_init(struct pci_dev *pdev) +{ + struct pci_host_bridge *hb = pci_find_host_bridge(pdev->bus); + u16 nr_link_ide, nr_ide_mem, nr_streams; + u16 ide_cap; + u32 val; + + /* + * Unconditionally init so that ida idle state is consistent with + * pdev->ide_cap. + */ + ida_init(&pdev->ide_stream_ida); + + if (!pci_is_pcie(pdev)) + return; + + ide_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_IDE); + if (!ide_cap) + return; + + pci_read_config_dword(pdev, ide_cap + PCI_IDE_CAP, &val); + if ((val & PCI_IDE_CAP_SELECTIVE) == 0) + return; + + /* + * Require endpoint IDE capability to be paired with IDE Root Port IDE + * capability. + */ + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ENDPOINT) { + struct pci_dev *rp = pcie_find_root_port(pdev); + + if (!rp->ide_cap) + return; + } + + pdev->ide_cfg = FIELD_GET(PCI_IDE_CAP_SEL_CFG, val); + pdev->ide_tee_limit = FIELD_GET(PCI_IDE_CAP_TEE_LIMITED, val); + + if (val & PCI_IDE_CAP_LINK) + nr_link_ide = 1 + FIELD_GET(PCI_IDE_CAP_LINK_TC_NUM, val); + else + nr_link_ide = 0; + + nr_ide_mem = 0; + nr_streams = 1 + FIELD_GET(PCI_IDE_CAP_SEL_NUM, val); + for (u16 i = 0; i < nr_streams; i++) { + int pos = __sel_ide_offset(ide_cap, nr_link_ide, i, nr_ide_mem); + int nr_assoc; + u32 val; + u8 id; + + pci_read_config_dword(pdev, pos + PCI_IDE_SEL_CAP, &val); + + /* + * Let's not entertain streams that do not have a constant + * number of address association blocks + */ + nr_assoc = FIELD_GET(PCI_IDE_SEL_CAP_ASSOC_NUM, val); + if (i && (nr_assoc != nr_ide_mem)) { + pci_info(pdev, "Unsupported Selective Stream %d capability, SKIP the rest\n", i); + nr_streams = i; + break; + } + + nr_ide_mem = nr_assoc; + + /* + * Claim Stream IDs and Selective Stream blocks that are already + * active on the device + */ + pci_read_config_dword(pdev, pos + PCI_IDE_SEL_CTL, &val); + id = FIELD_GET(PCI_IDE_SEL_CTL_ID, val); + if ((val & PCI_IDE_SEL_CTL_EN) && + !claim_stream(hb, id, pdev, i)) + return; + } + + /* Reserve link stream-ids that are already active on the device */ + for (u16 i = 0; i < nr_link_ide; ++i) { + int pos = ide_cap + PCI_IDE_LINK_STREAM_0 + i * PCI_IDE_LINK_BLOCK_SIZE; + u8 id; + + pci_read_config_dword(pdev, pos + PCI_IDE_LINK_CTL_0, &val); + id = FIELD_GET(PCI_IDE_LINK_CTL_ID, val); + if ((val & PCI_IDE_LINK_CTL_EN) && + !claim_stream(hb, id, NULL, -1)) + return; + } + + for (u16 i = 0; i < nr_streams; i++) { + int pos = __sel_ide_offset(ide_cap, nr_link_ide, i, nr_ide_mem); + + pci_read_config_dword(pdev, pos + PCI_IDE_SEL_CAP, &val); + if (val & PCI_IDE_SEL_CTL_EN) + continue; + val &= ~PCI_IDE_SEL_CTL_ID; + val |= FIELD_PREP(PCI_IDE_SEL_CTL_ID, PCI_IDE_RESERVED_STREAM_ID); + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_CTL, val); + } + + for (u16 i = 0; i < nr_link_ide; ++i) { + int pos = ide_cap + PCI_IDE_LINK_STREAM_0 + + i * PCI_IDE_LINK_BLOCK_SIZE; + + pci_read_config_dword(pdev, pos, &val); + if (val & PCI_IDE_LINK_CTL_EN) + continue; + val &= ~PCI_IDE_LINK_CTL_ID; + val |= FIELD_PREP(PCI_IDE_LINK_CTL_ID, PCI_IDE_RESERVED_STREAM_ID); + pci_write_config_dword(pdev, pos, val); + } + + pdev->ide_cap = ide_cap; + pdev->nr_link_ide = nr_link_ide; + pdev->nr_sel_ide = nr_streams; + pdev->nr_ide_mem = nr_ide_mem; +} + +struct stream_index { + struct ida *ida; + u8 stream_index; +}; + +static void free_stream_index(struct stream_index *stream) +{ + ida_free(stream->ida, stream->stream_index); +} + +DEFINE_FREE(free_stream, struct stream_index *, if (_T) free_stream_index(_T)) +static struct stream_index *alloc_stream_index(struct ida *ida, u16 max, + struct stream_index *stream) +{ + int id; + + if (!max) + return NULL; + + id = ida_alloc_max(ida, max - 1, GFP_KERNEL); + if (id < 0) + return NULL; + + *stream = (struct stream_index) { + .ida = ida, + .stream_index = id, + }; + return stream; +} + +/** + * pci_ide_stream_alloc() - Reserve stream indices and probe for settings + * @pdev: IDE capable PCIe Endpoint Physical Function + * + * Retrieve the Requester ID range of @pdev for programming its Root + * Port IDE RID Association registers, and conversely retrieve the + * Requester ID of the Root Port for programming @pdev's IDE RID + * Association registers. + * + * Allocate a Selective IDE Stream Register Block instance per port. + * + * Allocate a platform stream resource from the associated host bridge. + * Retrieve stream association parameters for Requester ID range and + * address range restrictions for the stream. + */ +struct pci_ide *pci_ide_stream_alloc(struct pci_dev *pdev) +{ + /* EP, RP, + HB Stream allocation */ + struct stream_index __stream[PCI_IDE_HB + 1]; + struct pci_bus_region pref_assoc = { 0, -1 }; + struct pci_bus_region mem_assoc = { 0, -1 }; + struct resource *mem, *pref; + struct pci_host_bridge *hb; + struct pci_dev *rp, *br; + int num_vf, rid_end; + + if (!pci_is_pcie(pdev)) + return NULL; + + if (pci_pcie_type(pdev) != PCI_EXP_TYPE_ENDPOINT) + return NULL; + + if (!pdev->ide_cap) + return NULL; + + struct pci_ide *ide __free(kfree) = kzalloc(sizeof(*ide), GFP_KERNEL); + if (!ide) + return NULL; + + hb = pci_find_host_bridge(pdev->bus); + struct stream_index *hb_stream __free(free_stream) = alloc_stream_index( + &hb->ide_stream_ida, hb->nr_ide_streams, &__stream[PCI_IDE_HB]); + if (!hb_stream) + return NULL; + + rp = pcie_find_root_port(pdev); + struct stream_index *rp_stream __free(free_stream) = alloc_stream_index( + &rp->ide_stream_ida, rp->nr_sel_ide, &__stream[PCI_IDE_RP]); + if (!rp_stream) + return NULL; + + struct stream_index *ep_stream __free(free_stream) = alloc_stream_index( + &pdev->ide_stream_ida, pdev->nr_sel_ide, &__stream[PCI_IDE_EP]); + if (!ep_stream) + return NULL; + + /* for SR-IOV case, cover all VFs */ + num_vf = pci_num_vf(pdev); + if (num_vf) + rid_end = PCI_DEVID(pci_iov_virtfn_bus(pdev, num_vf), + pci_iov_virtfn_devfn(pdev, num_vf)); + else + rid_end = pci_dev_id(pdev); + + br = pci_upstream_bridge(pdev); + if (!br) + return NULL; + + /* + * Check if the device consumes memory and/or prefetch-memory. Setup + * downstream address association ranges for each. + */ + mem = pci_resource_n(br, PCI_BRIDGE_MEM_WINDOW); + pref = pci_resource_n(br, PCI_BRIDGE_PREF_MEM_WINDOW); + if (resource_assigned(mem)) + pcibios_resource_to_bus(br->bus, &mem_assoc, mem); + if (resource_assigned(pref)) + pcibios_resource_to_bus(br->bus, &pref_assoc, pref); + + *ide = (struct pci_ide) { + .pdev = pdev, + .partner = { + [PCI_IDE_EP] = { + .rid_start = pci_dev_id(rp), + .rid_end = pci_dev_id(rp), + .stream_index = no_free_ptr(ep_stream)->stream_index, + /* Disable upstream address association */ + .mem_assoc = { 0, -1 }, + .pref_assoc = { 0, -1 }, + }, + [PCI_IDE_RP] = { + .rid_start = pci_dev_id(pdev), + .rid_end = rid_end, + .stream_index = no_free_ptr(rp_stream)->stream_index, + .mem_assoc = mem_assoc, + .pref_assoc = pref_assoc, + }, + }, + .host_bridge_stream = no_free_ptr(hb_stream)->stream_index, + .stream_id = -1, + }; + + return_ptr(ide); +} +EXPORT_SYMBOL_GPL(pci_ide_stream_alloc); + +/** + * pci_ide_stream_free() - unwind pci_ide_stream_alloc() + * @ide: idle IDE settings descriptor + * + * Free all of the stream index (register block) allocations acquired by + * pci_ide_stream_alloc(). The stream represented by @ide is assumed to + * be unregistered and not instantiated in any device. + */ +void pci_ide_stream_free(struct pci_ide *ide) +{ + struct pci_dev *pdev = ide->pdev; + struct pci_dev *rp = pcie_find_root_port(pdev); + struct pci_host_bridge *hb = pci_find_host_bridge(pdev->bus); + + ida_free(&pdev->ide_stream_ida, ide->partner[PCI_IDE_EP].stream_index); + ida_free(&rp->ide_stream_ida, ide->partner[PCI_IDE_RP].stream_index); + ida_free(&hb->ide_stream_ida, ide->host_bridge_stream); + kfree(ide); +} +EXPORT_SYMBOL_GPL(pci_ide_stream_free); + +/** + * pci_ide_stream_release() - unwind and release an @ide context + * @ide: partially or fully registered IDE settings descriptor + * + * In support of automatic cleanup of IDE setup routines perform IDE + * teardown in expected reverse order of setup and with respect to which + * aspects of IDE setup have successfully completed. + * + * Be careful that setup order mirrors this shutdown order. Otherwise, + * open code releasing the IDE context. + */ +void pci_ide_stream_release(struct pci_ide *ide) +{ + struct pci_dev *pdev = ide->pdev; + struct pci_dev *rp = pcie_find_root_port(pdev); + + if (ide->partner[PCI_IDE_RP].enable) + pci_ide_stream_disable(rp, ide); + + if (ide->partner[PCI_IDE_EP].enable) + pci_ide_stream_disable(pdev, ide); + + if (ide->tsm_dev) + tsm_ide_stream_unregister(ide); + + if (ide->partner[PCI_IDE_RP].setup) + pci_ide_stream_teardown(rp, ide); + + if (ide->partner[PCI_IDE_EP].setup) + pci_ide_stream_teardown(pdev, ide); + + if (ide->name) + pci_ide_stream_unregister(ide); + + pci_ide_stream_free(ide); +} +EXPORT_SYMBOL_GPL(pci_ide_stream_release); + +struct pci_ide_stream_id { + struct pci_host_bridge *hb; + u8 stream_id; +}; + +static struct pci_ide_stream_id * +request_stream_id(struct pci_host_bridge *hb, u8 stream_id, + struct pci_ide_stream_id *sid) +{ + if (!reserve_stream_id(hb, stream_id)) + return NULL; + + *sid = (struct pci_ide_stream_id) { + .hb = hb, + .stream_id = stream_id, + }; + + return sid; +} +DEFINE_FREE(free_stream_id, struct pci_ide_stream_id *, + if (_T) ida_free(&_T->hb->ide_stream_ids_ida, _T->stream_id)) + +/** + * pci_ide_stream_register() - Prepare to activate an IDE Stream + * @ide: IDE settings descriptor + * + * After a Stream ID has been acquired for @ide, record the presence of + * the stream in sysfs. The expectation is that @ide is immutable while + * registered. + */ +int pci_ide_stream_register(struct pci_ide *ide) +{ + struct pci_dev *pdev = ide->pdev; + struct pci_host_bridge *hb = pci_find_host_bridge(pdev->bus); + struct pci_ide_stream_id __sid; + u8 ep_stream, rp_stream; + int rc; + + if (ide->stream_id < 0 || ide->stream_id > U8_MAX) { + pci_err(pdev, "Setup fail: Invalid Stream ID: %d\n", ide->stream_id); + return -ENXIO; + } + + struct pci_ide_stream_id *sid __free(free_stream_id) = + request_stream_id(hb, ide->stream_id, &__sid); + if (!sid) { + pci_err(pdev, "Setup fail: Stream ID %d in use\n", ide->stream_id); + return -EBUSY; + } + + ep_stream = ide->partner[PCI_IDE_EP].stream_index; + rp_stream = ide->partner[PCI_IDE_RP].stream_index; + const char *name __free(kfree) = kasprintf(GFP_KERNEL, "stream%d.%d.%d", + ide->host_bridge_stream, + rp_stream, ep_stream); + if (!name) + return -ENOMEM; + + rc = sysfs_create_link(&hb->dev.kobj, &pdev->dev.kobj, name); + if (rc) + return rc; + + ide->name = no_free_ptr(name); + + /* Stream ID reservation recorded in @ide is now successfully registered */ + retain_and_null_ptr(sid); + + return 0; +} +EXPORT_SYMBOL_GPL(pci_ide_stream_register); + +/** + * pci_ide_stream_unregister() - unwind pci_ide_stream_register() + * @ide: idle IDE settings descriptor + * + * In preparation for freeing @ide, remove sysfs enumeration for the + * stream. + */ +void pci_ide_stream_unregister(struct pci_ide *ide) +{ + struct pci_dev *pdev = ide->pdev; + struct pci_host_bridge *hb = pci_find_host_bridge(pdev->bus); + + sysfs_remove_link(&hb->dev.kobj, ide->name); + kfree(ide->name); + ida_free(&hb->ide_stream_ids_ida, ide->stream_id); + ide->name = NULL; +} +EXPORT_SYMBOL_GPL(pci_ide_stream_unregister); + +static int pci_ide_domain(struct pci_dev *pdev) +{ + if (pdev->fm_enabled) + return pci_domain_nr(pdev->bus); + return 0; +} + +struct pci_ide_partner *pci_ide_to_settings(struct pci_dev *pdev, struct pci_ide *ide) +{ + if (!pci_is_pcie(pdev)) { + pci_warn_once(pdev, "not a PCIe device\n"); + return NULL; + } + + switch (pci_pcie_type(pdev)) { + case PCI_EXP_TYPE_ENDPOINT: + if (pdev != ide->pdev) { + pci_warn_once(pdev, "setup expected Endpoint: %s\n", pci_name(ide->pdev)); + return NULL; + } + return &ide->partner[PCI_IDE_EP]; + case PCI_EXP_TYPE_ROOT_PORT: { + struct pci_dev *rp = pcie_find_root_port(ide->pdev); + + if (pdev != rp) { + pci_warn_once(pdev, "setup expected Root Port: %s\n", + pci_name(rp)); + return NULL; + } + return &ide->partner[PCI_IDE_RP]; + } + default: + pci_warn_once(pdev, "invalid device type\n"); + return NULL; + } +} +EXPORT_SYMBOL_GPL(pci_ide_to_settings); + +static void set_ide_sel_ctl(struct pci_dev *pdev, struct pci_ide *ide, + struct pci_ide_partner *settings, int pos, + bool enable) +{ + u32 val = FIELD_PREP(PCI_IDE_SEL_CTL_ID, ide->stream_id) | + FIELD_PREP(PCI_IDE_SEL_CTL_DEFAULT, settings->default_stream) | + FIELD_PREP(PCI_IDE_SEL_CTL_CFG_EN, pdev->ide_cfg) | + FIELD_PREP(PCI_IDE_SEL_CTL_TEE_LIMITED, pdev->ide_tee_limit) | + FIELD_PREP(PCI_IDE_SEL_CTL_EN, enable); + + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_CTL, val); +} + +#define SEL_ADDR1_LOWER GENMASK(31, 20) +#define SEL_ADDR_UPPER GENMASK_ULL(63, 32) +#define PREP_PCI_IDE_SEL_ADDR1(base, limit) \ + (FIELD_PREP(PCI_IDE_SEL_ADDR_1_VALID, 1) | \ + FIELD_PREP(PCI_IDE_SEL_ADDR_1_BASE_LOW, \ + FIELD_GET(SEL_ADDR1_LOWER, (base))) | \ + FIELD_PREP(PCI_IDE_SEL_ADDR_1_LIMIT_LOW, \ + FIELD_GET(SEL_ADDR1_LOWER, (limit)))) + +static void mem_assoc_to_regs(struct pci_bus_region *region, + struct pci_ide_regs *regs, int idx) +{ + /* convert to u64 range for bitfield size checks */ + struct range r = { region->start, region->end }; + + regs->addr[idx].assoc1 = PREP_PCI_IDE_SEL_ADDR1(r.start, r.end); + regs->addr[idx].assoc2 = FIELD_GET(SEL_ADDR_UPPER, r.end); + regs->addr[idx].assoc3 = FIELD_GET(SEL_ADDR_UPPER, r.start); +} + +/** + * pci_ide_stream_to_regs() - convert IDE settings to association register values + * @pdev: PCIe device object for either a Root Port or Endpoint Partner Port + * @ide: registered IDE settings descriptor + * @regs: output register values + */ +static void pci_ide_stream_to_regs(struct pci_dev *pdev, struct pci_ide *ide, + struct pci_ide_regs *regs) +{ + struct pci_ide_partner *settings = pci_ide_to_settings(pdev, ide); + int assoc_idx = 0; + + memset(regs, 0, sizeof(*regs)); + + if (!settings) + return; + + regs->rid1 = FIELD_PREP(PCI_IDE_SEL_RID_1_LIMIT, settings->rid_end); + + regs->rid2 = FIELD_PREP(PCI_IDE_SEL_RID_2_VALID, 1) | + FIELD_PREP(PCI_IDE_SEL_RID_2_BASE, settings->rid_start) | + FIELD_PREP(PCI_IDE_SEL_RID_2_SEG, pci_ide_domain(pdev)); + + if (pdev->nr_ide_mem && pci_bus_region_size(&settings->mem_assoc)) { + mem_assoc_to_regs(&settings->mem_assoc, regs, assoc_idx); + assoc_idx++; + } + + if (pdev->nr_ide_mem > assoc_idx && + pci_bus_region_size(&settings->pref_assoc)) { + mem_assoc_to_regs(&settings->pref_assoc, regs, assoc_idx); + assoc_idx++; + } + + regs->nr_addr = assoc_idx; +} + +/** + * pci_ide_stream_setup() - program settings to Selective IDE Stream registers + * @pdev: PCIe device object for either a Root Port or Endpoint Partner Port + * @ide: registered IDE settings descriptor + * + * When @pdev is a PCI_EXP_TYPE_ENDPOINT then the PCI_IDE_EP partner + * settings are written to @pdev's Selective IDE Stream register block, + * and when @pdev is a PCI_EXP_TYPE_ROOT_PORT, the PCI_IDE_RP settings + * are selected. + */ +void pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide) +{ + struct pci_ide_partner *settings = pci_ide_to_settings(pdev, ide); + struct pci_ide_regs regs; + int pos; + + if (!settings) + return; + + pci_ide_stream_to_regs(pdev, ide, ®s); + + pos = sel_ide_offset(pdev, settings); + + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_1, regs.rid1); + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_2, regs.rid2); + + for (int i = 0; i < regs.nr_addr; i++) { + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_1(i), + regs.addr[i].assoc1); + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_2(i), + regs.addr[i].assoc2); + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_3(i), + regs.addr[i].assoc3); + } + + /* clear extra unused address association blocks */ + for (int i = regs.nr_addr; i < pdev->nr_ide_mem; i++) { + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_1(i), 0); + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_2(i), 0); + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_3(i), 0); + } + + /* + * Setup control register early for devices that expect + * stream_id is set during key programming. + */ + set_ide_sel_ctl(pdev, ide, settings, pos, false); + settings->setup = 1; +} +EXPORT_SYMBOL_GPL(pci_ide_stream_setup); + +/** + * pci_ide_stream_teardown() - disable the stream and clear all settings + * @pdev: PCIe device object for either a Root Port or Endpoint Partner Port + * @ide: registered IDE settings descriptor + * + * For stream destruction, zero all registers that may have been written + * by pci_ide_stream_setup(). Consider pci_ide_stream_disable() to leave + * settings in place while temporarily disabling the stream. + */ +void pci_ide_stream_teardown(struct pci_dev *pdev, struct pci_ide *ide) +{ + struct pci_ide_partner *settings = pci_ide_to_settings(pdev, ide); + int pos, i; + + if (!settings) + return; + + pos = sel_ide_offset(pdev, settings); + + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_CTL, 0); + + for (i = 0; i < pdev->nr_ide_mem; i++) { + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_1(i), 0); + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_2(i), 0); + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_3(i), 0); + } + + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_2, 0); + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_1, 0); + settings->setup = 0; +} +EXPORT_SYMBOL_GPL(pci_ide_stream_teardown); + +/** + * pci_ide_stream_enable() - enable a Selective IDE Stream + * @pdev: PCIe device object for either a Root Port or Endpoint Partner Port + * @ide: registered and setup IDE settings descriptor + * + * Activate the stream by writing to the Selective IDE Stream Control + * Register. + * + * Return: 0 if the stream successfully entered the "secure" state, and -EINVAL + * if @ide is invalid, and -ENXIO if the stream fails to enter the secure state. + * + * Note that the state may go "insecure" at any point after returning 0, but + * those events are equivalent to a "link down" event and handled via + * asynchronous error reporting. + * + * Caller is responsible to clear the enable bit in the -ENXIO case. + */ +int pci_ide_stream_enable(struct pci_dev *pdev, struct pci_ide *ide) +{ + struct pci_ide_partner *settings = pci_ide_to_settings(pdev, ide); + int pos; + u32 val; + + if (!settings) + return -EINVAL; + + pos = sel_ide_offset(pdev, settings); + + set_ide_sel_ctl(pdev, ide, settings, pos, true); + settings->enable = 1; + + pci_read_config_dword(pdev, pos + PCI_IDE_SEL_STS, &val); + if (FIELD_GET(PCI_IDE_SEL_STS_STATE, val) != + PCI_IDE_SEL_STS_STATE_SECURE) + return -ENXIO; + + return 0; +} +EXPORT_SYMBOL_GPL(pci_ide_stream_enable); + +/** + * pci_ide_stream_disable() - disable a Selective IDE Stream + * @pdev: PCIe device object for either a Root Port or Endpoint Partner Port + * @ide: registered and setup IDE settings descriptor + * + * Clear the Selective IDE Stream Control Register, but leave all other + * registers untouched. + */ +void pci_ide_stream_disable(struct pci_dev *pdev, struct pci_ide *ide) +{ + struct pci_ide_partner *settings = pci_ide_to_settings(pdev, ide); + int pos; + + if (!settings) + return; + + pos = sel_ide_offset(pdev, settings); + + pci_write_config_dword(pdev, pos + PCI_IDE_SEL_CTL, 0); + settings->enable = 0; +} +EXPORT_SYMBOL_GPL(pci_ide_stream_disable); + +void pci_ide_init_host_bridge(struct pci_host_bridge *hb) +{ + hb->nr_ide_streams = 256; + ida_init(&hb->ide_stream_ida); + ida_init(&hb->ide_stream_ids_ida); + reserve_stream_id(hb, PCI_IDE_RESERVED_STREAM_ID); +} + +static ssize_t available_secure_streams_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct pci_host_bridge *hb = to_pci_host_bridge(dev); + int nr = READ_ONCE(hb->nr_ide_streams); + int avail = nr; + + if (!nr) + return -ENXIO; + + /* + * Yes, this is inefficient and racy, but it is only for occasional + * platform resource surveys. Worst case is bounded to 256 streams. + */ + for (int i = 0; i < nr; i++) + if (ida_exists(&hb->ide_stream_ida, i)) + avail--; + return sysfs_emit(buf, "%d\n", avail); +} +static DEVICE_ATTR_RO(available_secure_streams); + +static struct attribute *pci_ide_attrs[] = { + &dev_attr_available_secure_streams.attr, + NULL +}; + +static umode_t pci_ide_attr_visible(struct kobject *kobj, struct attribute *a, int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct pci_host_bridge *hb = to_pci_host_bridge(dev); + + if (a == &dev_attr_available_secure_streams.attr) + if (!hb->nr_ide_streams) + return 0; + + return a->mode; +} + +const struct attribute_group pci_ide_attr_group = { + .attrs = pci_ide_attrs, + .is_visible = pci_ide_attr_visible, +}; + +/** + * pci_ide_set_nr_streams() - sets size of the pool of IDE Stream resources + * @hb: host bridge boundary for the stream pool + * @nr: number of streams + * + * Platform PCI init and/or expert test module use only. Limit IDE + * Stream establishment by setting the number of stream resources + * available at the host bridge. Platform init code must set this before + * the first pci_ide_stream_alloc() call if the platform has less than the + * default of 256 streams per host-bridge. + * + * The "PCI_IDE" symbol namespace is required because this is typically + * a detail that is settled in early PCI init. I.e. this export is not + * for endpoint drivers. + */ +void pci_ide_set_nr_streams(struct pci_host_bridge *hb, u16 nr) +{ + hb->nr_ide_streams = min(nr, 256); + WARN_ON_ONCE(!ida_is_empty(&hb->ide_stream_ida)); + sysfs_update_group(&hb->dev.kobj, &pci_ide_attr_group); +} +EXPORT_SYMBOL_NS_GPL(pci_ide_set_nr_streams, "PCI_IDE"); + +void pci_ide_destroy(struct pci_dev *pdev) +{ + ida_destroy(&pdev->ide_stream_ida); +} |