diff options
Diffstat (limited to 'drivers/infiniband/hw/hfi1/pcie.c')
| -rw-r--r-- | drivers/infiniband/hw/hfi1/pcie.c | 1471 |
1 files changed, 1471 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/hfi1/pcie.c b/drivers/infiniband/hw/hfi1/pcie.c new file mode 100644 index 000000000..a8dd12e52 --- /dev/null +++ b/drivers/infiniband/hw/hfi1/pcie.c @@ -0,0 +1,1471 @@ +/* + * Copyright(c) 2015 - 2017 Intel Corporation. + * + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License 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. + * + * BSD LICENSE + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * - Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * - Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +#include <linux/pci.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/vmalloc.h> +#include <linux/aer.h> +#include <linux/module.h> + +#include "hfi.h" +#include "chip_registers.h" +#include "aspm.h" + +/* + * This file contains PCIe utility routines. + */ + +/* + * Code to adjust PCIe capabilities. + */ +static void tune_pcie_caps(struct hfi1_devdata *); + +/* + * Do all the common PCIe setup and initialization. + * devdata is not yet allocated, and is not allocated until after this + * routine returns success. Therefore dd_dev_err() can't be used for error + * printing. + */ +int hfi1_pcie_init(struct pci_dev *pdev, const struct pci_device_id *ent) +{ + int ret; + + ret = pci_enable_device(pdev); + if (ret) { + /* + * This can happen (in theory) iff: + * We did a chip reset, and then failed to reprogram the + * BAR, or the chip reset due to an internal error. We then + * unloaded the driver and reloaded it. + * + * Both reset cases set the BAR back to initial state. For + * the latter case, the AER sticky error bit at offset 0x718 + * should be set, but the Linux kernel doesn't yet know + * about that, it appears. If the original BAR was retained + * in the kernel data structures, this may be OK. + */ + hfi1_early_err(&pdev->dev, "pci enable failed: error %d\n", + -ret); + goto done; + } + + ret = pci_request_regions(pdev, DRIVER_NAME); + if (ret) { + hfi1_early_err(&pdev->dev, + "pci_request_regions fails: err %d\n", -ret); + goto bail; + } + + ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(64)); + if (ret) { + /* + * If the 64 bit setup fails, try 32 bit. Some systems + * do not setup 64 bit maps on systems with 2GB or less + * memory installed. + */ + ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32)); + if (ret) { + hfi1_early_err(&pdev->dev, + "Unable to set DMA mask: %d\n", ret); + goto bail; + } + ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)); + } else { + ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64)); + } + if (ret) { + hfi1_early_err(&pdev->dev, + "Unable to set DMA consistent mask: %d\n", ret); + goto bail; + } + + pci_set_master(pdev); + (void)pci_enable_pcie_error_reporting(pdev); + goto done; + +bail: + hfi1_pcie_cleanup(pdev); +done: + return ret; +} + +/* + * Clean what was done in hfi1_pcie_init() + */ +void hfi1_pcie_cleanup(struct pci_dev *pdev) +{ + pci_disable_device(pdev); + /* + * Release regions should be called after the disable. OK to + * call if request regions has not been called or failed. + */ + pci_release_regions(pdev); +} + +/* + * Do remaining PCIe setup, once dd is allocated, and save away + * fields required to re-initialize after a chip reset, or for + * various other purposes + */ +int hfi1_pcie_ddinit(struct hfi1_devdata *dd, struct pci_dev *pdev) +{ + unsigned long len; + resource_size_t addr; + int ret = 0; + u32 rcv_array_count; + + addr = pci_resource_start(pdev, 0); + len = pci_resource_len(pdev, 0); + + /* + * The TXE PIO buffers are at the tail end of the chip space. + * Cut them off and map them separately. + */ + + /* sanity check vs expectations */ + if (len != TXE_PIO_SEND + TXE_PIO_SIZE) { + dd_dev_err(dd, "chip PIO range does not match\n"); + return -EINVAL; + } + + dd->kregbase1 = ioremap_nocache(addr, RCV_ARRAY); + if (!dd->kregbase1) { + dd_dev_err(dd, "UC mapping of kregbase1 failed\n"); + return -ENOMEM; + } + dd_dev_info(dd, "UC base1: %p for %x\n", dd->kregbase1, RCV_ARRAY); + + /* verify that reads actually work, save revision for reset check */ + dd->revision = readq(dd->kregbase1 + CCE_REVISION); + if (dd->revision == ~(u64)0) { + dd_dev_err(dd, "Cannot read chip CSRs\n"); + goto nomem; + } + + rcv_array_count = readq(dd->kregbase1 + RCV_ARRAY_CNT); + dd_dev_info(dd, "RcvArray count: %u\n", rcv_array_count); + dd->base2_start = RCV_ARRAY + rcv_array_count * 8; + + dd->kregbase2 = ioremap_nocache( + addr + dd->base2_start, + TXE_PIO_SEND - dd->base2_start); + if (!dd->kregbase2) { + dd_dev_err(dd, "UC mapping of kregbase2 failed\n"); + goto nomem; + } + dd_dev_info(dd, "UC base2: %p for %x\n", dd->kregbase2, + TXE_PIO_SEND - dd->base2_start); + + dd->piobase = ioremap_wc(addr + TXE_PIO_SEND, TXE_PIO_SIZE); + if (!dd->piobase) { + dd_dev_err(dd, "WC mapping of send buffers failed\n"); + goto nomem; + } + dd_dev_info(dd, "WC piobase: %p\n for %x", dd->piobase, TXE_PIO_SIZE); + + dd->physaddr = addr; /* used for io_remap, etc. */ + + /* + * Map the chip's RcvArray as write-combining to allow us + * to write an entire cacheline worth of entries in one shot. + */ + dd->rcvarray_wc = ioremap_wc(addr + RCV_ARRAY, + rcv_array_count * 8); + if (!dd->rcvarray_wc) { + dd_dev_err(dd, "WC mapping of receive array failed\n"); + goto nomem; + } + dd_dev_info(dd, "WC RcvArray: %p for %x\n", + dd->rcvarray_wc, rcv_array_count * 8); + + dd->flags |= HFI1_PRESENT; /* chip.c CSR routines now work */ + return 0; +nomem: + ret = -ENOMEM; + hfi1_pcie_ddcleanup(dd); + return ret; +} + +/* + * Do PCIe cleanup related to dd, after chip-specific cleanup, etc. Just prior + * to releasing the dd memory. + * Void because all of the core pcie cleanup functions are void. + */ +void hfi1_pcie_ddcleanup(struct hfi1_devdata *dd) +{ + dd->flags &= ~HFI1_PRESENT; + if (dd->kregbase1) + iounmap(dd->kregbase1); + dd->kregbase1 = NULL; + if (dd->kregbase2) + iounmap(dd->kregbase2); + dd->kregbase2 = NULL; + if (dd->rcvarray_wc) + iounmap(dd->rcvarray_wc); + dd->rcvarray_wc = NULL; + if (dd->piobase) + iounmap(dd->piobase); + dd->piobase = NULL; +} + +/* return the PCIe link speed from the given link status */ +static u32 extract_speed(u16 linkstat) +{ + u32 speed; + + switch (linkstat & PCI_EXP_LNKSTA_CLS) { + default: /* not defined, assume Gen1 */ + case PCI_EXP_LNKSTA_CLS_2_5GB: + speed = 2500; /* Gen 1, 2.5GHz */ + break; + case PCI_EXP_LNKSTA_CLS_5_0GB: + speed = 5000; /* Gen 2, 5GHz */ + break; + case PCI_EXP_LNKSTA_CLS_8_0GB: + speed = 8000; /* Gen 3, 8GHz */ + break; + } + return speed; +} + +/* return the PCIe link speed from the given link status */ +static u32 extract_width(u16 linkstat) +{ + return (linkstat & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT; +} + +/* read the link status and set dd->{lbus_width,lbus_speed,lbus_info} */ +static void update_lbus_info(struct hfi1_devdata *dd) +{ + u16 linkstat; + int ret; + + ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKSTA, &linkstat); + if (ret) { + dd_dev_err(dd, "Unable to read from PCI config\n"); + return; + } + + dd->lbus_width = extract_width(linkstat); + dd->lbus_speed = extract_speed(linkstat); + snprintf(dd->lbus_info, sizeof(dd->lbus_info), + "PCIe,%uMHz,x%u", dd->lbus_speed, dd->lbus_width); +} + +/* + * Read in the current PCIe link width and speed. Find if the link is + * Gen3 capable. + */ +int pcie_speeds(struct hfi1_devdata *dd) +{ + u32 linkcap; + struct pci_dev *parent = dd->pcidev->bus->self; + int ret; + + if (!pci_is_pcie(dd->pcidev)) { + dd_dev_err(dd, "Can't find PCI Express capability!\n"); + return -EINVAL; + } + + /* find if our max speed is Gen3 and parent supports Gen3 speeds */ + dd->link_gen3_capable = 1; + + ret = pcie_capability_read_dword(dd->pcidev, PCI_EXP_LNKCAP, &linkcap); + if (ret) { + dd_dev_err(dd, "Unable to read from PCI config\n"); + return ret; + } + + if ((linkcap & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_8_0GB) { + dd_dev_info(dd, + "This HFI is not Gen3 capable, max speed 0x%x, need 0x3\n", + linkcap & PCI_EXP_LNKCAP_SLS); + dd->link_gen3_capable = 0; + } + + /* + * bus->max_bus_speed is set from the bridge's linkcap Max Link Speed + */ + if (parent && + (dd->pcidev->bus->max_bus_speed == PCIE_SPEED_2_5GT || + dd->pcidev->bus->max_bus_speed == PCIE_SPEED_5_0GT)) { + dd_dev_info(dd, "Parent PCIe bridge does not support Gen3\n"); + dd->link_gen3_capable = 0; + } + + /* obtain the link width and current speed */ + update_lbus_info(dd); + + dd_dev_info(dd, "%s\n", dd->lbus_info); + + return 0; +} + +/* + * Returns: + * - actual number of interrupts allocated or + * - error + */ +int request_msix(struct hfi1_devdata *dd, u32 msireq) +{ + int nvec; + + nvec = pci_alloc_irq_vectors(dd->pcidev, msireq, msireq, PCI_IRQ_MSIX); + if (nvec < 0) { + dd_dev_err(dd, "pci_alloc_irq_vectors() failed: %d\n", nvec); + return nvec; + } + + tune_pcie_caps(dd); + + return nvec; +} + +/* restore command and BARs after a reset has wiped them out */ +int restore_pci_variables(struct hfi1_devdata *dd) +{ + int ret = 0; + + ret = pci_write_config_word(dd->pcidev, PCI_COMMAND, dd->pci_command); + if (ret) + goto error; + + ret = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0, + dd->pcibar0); + if (ret) + goto error; + + ret = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1, + dd->pcibar1); + if (ret) + goto error; + + ret = pci_write_config_dword(dd->pcidev, PCI_ROM_ADDRESS, dd->pci_rom); + if (ret) + goto error; + + ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL, + dd->pcie_devctl); + if (ret) + goto error; + + ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL, + dd->pcie_lnkctl); + if (ret) + goto error; + + ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL2, + dd->pcie_devctl2); + if (ret) + goto error; + + ret = pci_write_config_dword(dd->pcidev, PCI_CFG_MSIX0, dd->pci_msix0); + if (ret) + goto error; + + if (pci_find_ext_capability(dd->pcidev, PCI_EXT_CAP_ID_TPH)) { + ret = pci_write_config_dword(dd->pcidev, PCIE_CFG_TPH2, + dd->pci_tph2); + if (ret) + goto error; + } + return 0; + +error: + dd_dev_err(dd, "Unable to write to PCI config\n"); + return ret; +} + +/* Save BARs and command to rewrite after device reset */ +int save_pci_variables(struct hfi1_devdata *dd) +{ + int ret = 0; + + ret = pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0, + &dd->pcibar0); + if (ret) + goto error; + + ret = pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1, + &dd->pcibar1); + if (ret) + goto error; + + ret = pci_read_config_dword(dd->pcidev, PCI_ROM_ADDRESS, &dd->pci_rom); + if (ret) + goto error; + + ret = pci_read_config_word(dd->pcidev, PCI_COMMAND, &dd->pci_command); + if (ret) + goto error; + + ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL, + &dd->pcie_devctl); + if (ret) + goto error; + + ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL, + &dd->pcie_lnkctl); + if (ret) + goto error; + + ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL2, + &dd->pcie_devctl2); + if (ret) + goto error; + + ret = pci_read_config_dword(dd->pcidev, PCI_CFG_MSIX0, &dd->pci_msix0); + if (ret) + goto error; + + if (pci_find_ext_capability(dd->pcidev, PCI_EXT_CAP_ID_TPH)) { + ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_TPH2, + &dd->pci_tph2); + if (ret) + goto error; + } + return 0; + +error: + dd_dev_err(dd, "Unable to read from PCI config\n"); + return ret; +} + +/* + * BIOS may not set PCIe bus-utilization parameters for best performance. + * Check and optionally adjust them to maximize our throughput. + */ +static int hfi1_pcie_caps; +module_param_named(pcie_caps, hfi1_pcie_caps, int, S_IRUGO); +MODULE_PARM_DESC(pcie_caps, "Max PCIe tuning: Payload (0..3), ReadReq (4..7)"); + +uint aspm_mode = ASPM_MODE_DISABLED; +module_param_named(aspm, aspm_mode, uint, S_IRUGO); +MODULE_PARM_DESC(aspm, "PCIe ASPM: 0: disable, 1: enable, 2: dynamic"); + +static void tune_pcie_caps(struct hfi1_devdata *dd) +{ + struct pci_dev *parent; + u16 rc_mpss, rc_mps, ep_mpss, ep_mps; + u16 rc_mrrs, ep_mrrs, max_mrrs, ectl; + int ret; + + /* + * Turn on extended tags in DevCtl in case the BIOS has turned it off + * to improve WFR SDMA bandwidth + */ + ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL, &ectl); + if ((!ret) && !(ectl & PCI_EXP_DEVCTL_EXT_TAG)) { + dd_dev_info(dd, "Enabling PCIe extended tags\n"); + ectl |= PCI_EXP_DEVCTL_EXT_TAG; + ret = pcie_capability_write_word(dd->pcidev, + PCI_EXP_DEVCTL, ectl); + if (ret) + dd_dev_info(dd, "Unable to write to PCI config\n"); + } + /* Find out supported and configured values for parent (root) */ + parent = dd->pcidev->bus->self; + /* + * The driver cannot perform the tuning if it does not have + * access to the upstream component. + */ + if (!parent) { + dd_dev_info(dd, "Parent not found\n"); + return; + } + if (!pci_is_root_bus(parent->bus)) { + dd_dev_info(dd, "Parent not root\n"); + return; + } + if (!pci_is_pcie(parent)) { + dd_dev_info(dd, "Parent is not PCI Express capable\n"); + return; + } + if (!pci_is_pcie(dd->pcidev)) { + dd_dev_info(dd, "PCI device is not PCI Express capable\n"); + return; + } + rc_mpss = parent->pcie_mpss; + rc_mps = ffs(pcie_get_mps(parent)) - 8; + /* Find out supported and configured values for endpoint (us) */ + ep_mpss = dd->pcidev->pcie_mpss; + ep_mps = ffs(pcie_get_mps(dd->pcidev)) - 8; + + /* Find max payload supported by root, endpoint */ + if (rc_mpss > ep_mpss) + rc_mpss = ep_mpss; + + /* If Supported greater than limit in module param, limit it */ + if (rc_mpss > (hfi1_pcie_caps & 7)) + rc_mpss = hfi1_pcie_caps & 7; + /* If less than (allowed, supported), bump root payload */ + if (rc_mpss > rc_mps) { + rc_mps = rc_mpss; + pcie_set_mps(parent, 128 << rc_mps); + } + /* If less than (allowed, supported), bump endpoint payload */ + if (rc_mpss > ep_mps) { + ep_mps = rc_mpss; + pcie_set_mps(dd->pcidev, 128 << ep_mps); + } + + /* + * Now the Read Request size. + * No field for max supported, but PCIe spec limits it to 4096, + * which is code '5' (log2(4096) - 7) + */ + max_mrrs = 5; + if (max_mrrs > ((hfi1_pcie_caps >> 4) & 7)) + max_mrrs = (hfi1_pcie_caps >> 4) & 7; + + max_mrrs = 128 << max_mrrs; + rc_mrrs = pcie_get_readrq(parent); + ep_mrrs = pcie_get_readrq(dd->pcidev); + + if (max_mrrs > rc_mrrs) { + rc_mrrs = max_mrrs; + pcie_set_readrq(parent, rc_mrrs); + } + if (max_mrrs > ep_mrrs) { + ep_mrrs = max_mrrs; + pcie_set_readrq(dd->pcidev, ep_mrrs); + } +} + +/* End of PCIe capability tuning */ + +/* + * From here through hfi1_pci_err_handler definition is invoked via + * PCI error infrastructure, registered via pci + */ +static pci_ers_result_t +pci_error_detected(struct pci_dev *pdev, pci_channel_state_t state) +{ + struct hfi1_devdata *dd = pci_get_drvdata(pdev); + pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED; + + switch (state) { + case pci_channel_io_normal: + dd_dev_info(dd, "State Normal, ignoring\n"); + break; + + case pci_channel_io_frozen: + dd_dev_info(dd, "State Frozen, requesting reset\n"); + pci_disable_device(pdev); + ret = PCI_ERS_RESULT_NEED_RESET; + break; + + case pci_channel_io_perm_failure: + if (dd) { + dd_dev_info(dd, "State Permanent Failure, disabling\n"); + /* no more register accesses! */ + dd->flags &= ~HFI1_PRESENT; + hfi1_disable_after_error(dd); + } + /* else early, or other problem */ + ret = PCI_ERS_RESULT_DISCONNECT; + break; + + default: /* shouldn't happen */ + dd_dev_info(dd, "HFI1 PCI errors detected (state %d)\n", + state); + break; + } + return ret; +} + +static pci_ers_result_t +pci_mmio_enabled(struct pci_dev *pdev) +{ + u64 words = 0U; + struct hfi1_devdata *dd = pci_get_drvdata(pdev); + pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED; + + if (dd && dd->pport) { + words = read_port_cntr(dd->pport, C_RX_WORDS, CNTR_INVALID_VL); + if (words == ~0ULL) + ret = PCI_ERS_RESULT_NEED_RESET; + dd_dev_info(dd, + "HFI1 mmio_enabled function called, read wordscntr %llx, returning %d\n", + words, ret); + } + return ret; +} + +static pci_ers_result_t +pci_slot_reset(struct pci_dev *pdev) +{ + struct hfi1_devdata *dd = pci_get_drvdata(pdev); + + dd_dev_info(dd, "HFI1 slot_reset function called, ignored\n"); + return PCI_ERS_RESULT_CAN_RECOVER; +} + +static void +pci_resume(struct pci_dev *pdev) +{ + struct hfi1_devdata *dd = pci_get_drvdata(pdev); + + dd_dev_info(dd, "HFI1 resume function called\n"); + pci_cleanup_aer_uncorrect_error_status(pdev); + /* + * Running jobs will fail, since it's asynchronous + * unlike sysfs-requested reset. Better than + * doing nothing. + */ + hfi1_init(dd, 1); /* same as re-init after reset */ +} + +const struct pci_error_handlers hfi1_pci_err_handler = { + .error_detected = pci_error_detected, + .mmio_enabled = pci_mmio_enabled, + .slot_reset = pci_slot_reset, + .resume = pci_resume, +}; + +/*============================================================================*/ +/* PCIe Gen3 support */ + +/* + * This code is separated out because it is expected to be removed in the + * final shipping product. If not, then it will be revisited and items + * will be moved to more standard locations. + */ + +/* ASIC_PCI_SD_HOST_STATUS.FW_DNLD_STS field values */ +#define DL_STATUS_HFI0 0x1 /* hfi0 firmware download complete */ +#define DL_STATUS_HFI1 0x2 /* hfi1 firmware download complete */ +#define DL_STATUS_BOTH 0x3 /* hfi0 and hfi1 firmware download complete */ + +/* ASIC_PCI_SD_HOST_STATUS.FW_DNLD_ERR field values */ +#define DL_ERR_NONE 0x0 /* no error */ +#define DL_ERR_SWAP_PARITY 0x1 /* parity error in SerDes interrupt */ + /* or response data */ +#define DL_ERR_DISABLED 0x2 /* hfi disabled */ +#define DL_ERR_SECURITY 0x3 /* security check failed */ +#define DL_ERR_SBUS 0x4 /* SBus status error */ +#define DL_ERR_XFR_PARITY 0x5 /* parity error during ROM transfer*/ + +/* gasket block secondary bus reset delay */ +#define SBR_DELAY_US 200000 /* 200ms */ + +static uint pcie_target = 3; +module_param(pcie_target, uint, S_IRUGO); +MODULE_PARM_DESC(pcie_target, "PCIe target speed (0 skip, 1-3 Gen1-3)"); + +static uint pcie_force; +module_param(pcie_force, uint, S_IRUGO); +MODULE_PARM_DESC(pcie_force, "Force driver to do a PCIe firmware download even if already at target speed"); + +static uint pcie_retry = 5; +module_param(pcie_retry, uint, S_IRUGO); +MODULE_PARM_DESC(pcie_retry, "Driver will try this many times to reach requested speed"); + +#define UNSET_PSET 255 +#define DEFAULT_DISCRETE_PSET 2 /* discrete HFI */ +#define DEFAULT_MCP_PSET 6 /* MCP HFI */ +static uint pcie_pset = UNSET_PSET; +module_param(pcie_pset, uint, S_IRUGO); +MODULE_PARM_DESC(pcie_pset, "PCIe Eq Pset value to use, range is 0-10"); + +static uint pcie_ctle = 3; /* discrete on, integrated on */ +module_param(pcie_ctle, uint, S_IRUGO); +MODULE_PARM_DESC(pcie_ctle, "PCIe static CTLE mode, bit 0 - discrete on/off, bit 1 - integrated on/off"); + +/* equalization columns */ +#define PREC 0 +#define ATTN 1 +#define POST 2 + +/* discrete silicon preliminary equalization values */ +static const u8 discrete_preliminary_eq[11][3] = { + /* prec attn post */ + { 0x00, 0x00, 0x12 }, /* p0 */ + { 0x00, 0x00, 0x0c }, /* p1 */ + { 0x00, 0x00, 0x0f }, /* p2 */ + { 0x00, 0x00, 0x09 }, /* p3 */ + { 0x00, 0x00, 0x00 }, /* p4 */ + { 0x06, 0x00, 0x00 }, /* p5 */ + { 0x09, 0x00, 0x00 }, /* p6 */ + { 0x06, 0x00, 0x0f }, /* p7 */ + { 0x09, 0x00, 0x09 }, /* p8 */ + { 0x0c, 0x00, 0x00 }, /* p9 */ + { 0x00, 0x00, 0x18 }, /* p10 */ +}; + +/* integrated silicon preliminary equalization values */ +static const u8 integrated_preliminary_eq[11][3] = { + /* prec attn post */ + { 0x00, 0x1e, 0x07 }, /* p0 */ + { 0x00, 0x1e, 0x05 }, /* p1 */ + { 0x00, 0x1e, 0x06 }, /* p2 */ + { 0x00, 0x1e, 0x04 }, /* p3 */ + { 0x00, 0x1e, 0x00 }, /* p4 */ + { 0x03, 0x1e, 0x00 }, /* p5 */ + { 0x04, 0x1e, 0x00 }, /* p6 */ + { 0x03, 0x1e, 0x06 }, /* p7 */ + { 0x03, 0x1e, 0x04 }, /* p8 */ + { 0x05, 0x1e, 0x00 }, /* p9 */ + { 0x00, 0x1e, 0x0a }, /* p10 */ +}; + +static const u8 discrete_ctle_tunings[11][4] = { + /* DC LF HF BW */ + { 0x48, 0x0b, 0x04, 0x04 }, /* p0 */ + { 0x60, 0x05, 0x0f, 0x0a }, /* p1 */ + { 0x50, 0x09, 0x06, 0x06 }, /* p2 */ + { 0x68, 0x05, 0x0f, 0x0a }, /* p3 */ + { 0x80, 0x05, 0x0f, 0x0a }, /* p4 */ + { 0x70, 0x05, 0x0f, 0x0a }, /* p5 */ + { 0x68, 0x05, 0x0f, 0x0a }, /* p6 */ + { 0x38, 0x0f, 0x00, 0x00 }, /* p7 */ + { 0x48, 0x09, 0x06, 0x06 }, /* p8 */ + { 0x60, 0x05, 0x0f, 0x0a }, /* p9 */ + { 0x38, 0x0f, 0x00, 0x00 }, /* p10 */ +}; + +static const u8 integrated_ctle_tunings[11][4] = { + /* DC LF HF BW */ + { 0x38, 0x0f, 0x00, 0x00 }, /* p0 */ + { 0x38, 0x0f, 0x00, 0x00 }, /* p1 */ + { 0x38, 0x0f, 0x00, 0x00 }, /* p2 */ + { 0x38, 0x0f, 0x00, 0x00 }, /* p3 */ + { 0x58, 0x0a, 0x05, 0x05 }, /* p4 */ + { 0x48, 0x0a, 0x05, 0x05 }, /* p5 */ + { 0x40, 0x0a, 0x05, 0x05 }, /* p6 */ + { 0x38, 0x0f, 0x00, 0x00 }, /* p7 */ + { 0x38, 0x0f, 0x00, 0x00 }, /* p8 */ + { 0x38, 0x09, 0x06, 0x06 }, /* p9 */ + { 0x38, 0x0e, 0x01, 0x01 }, /* p10 */ +}; + +/* helper to format the value to write to hardware */ +#define eq_value(pre, curr, post) \ + ((((u32)(pre)) << \ + PCIE_CFG_REG_PL102_GEN3_EQ_PRE_CURSOR_PSET_SHIFT) \ + | (((u32)(curr)) << PCIE_CFG_REG_PL102_GEN3_EQ_CURSOR_PSET_SHIFT) \ + | (((u32)(post)) << \ + PCIE_CFG_REG_PL102_GEN3_EQ_POST_CURSOR_PSET_SHIFT)) + +/* + * Load the given EQ preset table into the PCIe hardware. + */ +static int load_eq_table(struct hfi1_devdata *dd, const u8 eq[11][3], u8 fs, + u8 div) +{ + struct pci_dev *pdev = dd->pcidev; + u32 hit_error = 0; + u32 violation; + u32 i; + u8 c_minus1, c0, c_plus1; + int ret; + + for (i = 0; i < 11; i++) { + /* set index */ + pci_write_config_dword(pdev, PCIE_CFG_REG_PL103, i); + /* write the value */ + c_minus1 = eq[i][PREC] / div; + c0 = fs - (eq[i][PREC] / div) - (eq[i][POST] / div); + c_plus1 = eq[i][POST] / div; + pci_write_config_dword(pdev, PCIE_CFG_REG_PL102, + eq_value(c_minus1, c0, c_plus1)); + /* check if these coefficients violate EQ rules */ + ret = pci_read_config_dword(dd->pcidev, + PCIE_CFG_REG_PL105, &violation); + if (ret) { + dd_dev_err(dd, "Unable to read from PCI config\n"); + hit_error = 1; + break; + } + + if (violation + & PCIE_CFG_REG_PL105_GEN3_EQ_VIOLATE_COEF_RULES_SMASK){ + if (hit_error == 0) { + dd_dev_err(dd, + "Gen3 EQ Table Coefficient rule violations\n"); + dd_dev_err(dd, " prec attn post\n"); + } + dd_dev_err(dd, " p%02d: %02x %02x %02x\n", + i, (u32)eq[i][0], (u32)eq[i][1], + (u32)eq[i][2]); + dd_dev_err(dd, " %02x %02x %02x\n", + (u32)c_minus1, (u32)c0, (u32)c_plus1); + hit_error = 1; + } + } + if (hit_error) + return -EINVAL; + return 0; +} + +/* + * Steps to be done after the PCIe firmware is downloaded and + * before the SBR for the Pcie Gen3. + * The SBus resource is already being held. + */ +static void pcie_post_steps(struct hfi1_devdata *dd) +{ + int i; + + set_sbus_fast_mode(dd); + /* + * Write to the PCIe PCSes to set the G3_LOCKED_NEXT bits to 1. + * This avoids a spurious framing error that can otherwise be + * generated by the MAC layer. + * + * Use individual addresses since no broadcast is set up. + */ + for (i = 0; i < NUM_PCIE_SERDES; i++) { + sbus_request(dd, pcie_pcs_addrs[dd->hfi1_id][i], + 0x03, WRITE_SBUS_RECEIVER, 0x00022132); + } + + clear_sbus_fast_mode(dd); +} + +/* + * Trigger a secondary bus reset (SBR) on ourselves using our parent. + * + * Based on pci_parent_bus_reset() which is not exported by the + * kernel core. + */ +static int trigger_sbr(struct hfi1_devdata *dd) +{ + struct pci_dev *dev = dd->pcidev; + struct pci_dev *pdev; + + /* need a parent */ + if (!dev->bus->self) { + dd_dev_err(dd, "%s: no parent device\n", __func__); + return -ENOTTY; + } + + /* should not be anyone else on the bus */ + list_for_each_entry(pdev, &dev->bus->devices, bus_list) + if (pdev != dev) { + dd_dev_err(dd, + "%s: another device is on the same bus\n", + __func__); + return -ENOTTY; + } + + /* + * This is an end around to do an SBR during probe time. A new API needs + * to be implemented to have cleaner interface but this fixes the + * current brokenness + */ + return pci_bridge_secondary_bus_reset(dev->bus->self); +} + +/* + * Write the given gasket interrupt register. + */ +static void write_gasket_interrupt(struct hfi1_devdata *dd, int index, + u16 code, u16 data) +{ + write_csr(dd, ASIC_PCIE_SD_INTRPT_LIST + (index * 8), + (((u64)code << ASIC_PCIE_SD_INTRPT_LIST_INTRPT_CODE_SHIFT) | + ((u64)data << ASIC_PCIE_SD_INTRPT_LIST_INTRPT_DATA_SHIFT))); +} + +/* + * Tell the gasket logic how to react to the reset. + */ +static void arm_gasket_logic(struct hfi1_devdata *dd) +{ + u64 reg; + + reg = (((u64)1 << dd->hfi1_id) << + ASIC_PCIE_SD_HOST_CMD_INTRPT_CMD_SHIFT) | + ((u64)pcie_serdes_broadcast[dd->hfi1_id] << + ASIC_PCIE_SD_HOST_CMD_SBUS_RCVR_ADDR_SHIFT | + ASIC_PCIE_SD_HOST_CMD_SBR_MODE_SMASK | + ((u64)SBR_DELAY_US & ASIC_PCIE_SD_HOST_CMD_TIMER_MASK) << + ASIC_PCIE_SD_HOST_CMD_TIMER_SHIFT); + write_csr(dd, ASIC_PCIE_SD_HOST_CMD, reg); + /* read back to push the write */ + read_csr(dd, ASIC_PCIE_SD_HOST_CMD); +} + +/* + * CCE_PCIE_CTRL long name helpers + * We redefine these shorter macros to use in the code while leaving + * chip_registers.h to be autogenerated from the hardware spec. + */ +#define LANE_BUNDLE_MASK CCE_PCIE_CTRL_PCIE_LANE_BUNDLE_MASK +#define LANE_BUNDLE_SHIFT CCE_PCIE_CTRL_PCIE_LANE_BUNDLE_SHIFT +#define LANE_DELAY_MASK CCE_PCIE_CTRL_PCIE_LANE_DELAY_MASK +#define LANE_DELAY_SHIFT CCE_PCIE_CTRL_PCIE_LANE_DELAY_SHIFT +#define MARGIN_OVERWRITE_ENABLE_SHIFT CCE_PCIE_CTRL_XMT_MARGIN_OVERWRITE_ENABLE_SHIFT +#define MARGIN_SHIFT CCE_PCIE_CTRL_XMT_MARGIN_SHIFT +#define MARGIN_G1_G2_OVERWRITE_MASK CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_OVERWRITE_ENABLE_MASK +#define MARGIN_G1_G2_OVERWRITE_SHIFT CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_OVERWRITE_ENABLE_SHIFT +#define MARGIN_GEN1_GEN2_MASK CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_MASK +#define MARGIN_GEN1_GEN2_SHIFT CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_SHIFT + + /* + * Write xmt_margin for full-swing (WFR-B) or half-swing (WFR-C). + */ +static void write_xmt_margin(struct hfi1_devdata *dd, const char *fname) +{ + u64 pcie_ctrl; + u64 xmt_margin; + u64 xmt_margin_oe; + u64 lane_delay; + u64 lane_bundle; + + pcie_ctrl = read_csr(dd, CCE_PCIE_CTRL); + + /* + * For Discrete, use full-swing. + * - PCIe TX defaults to full-swing. + * Leave this register as default. + * For Integrated, use half-swing + * - Copy xmt_margin and xmt_margin_oe + * from Gen1/Gen2 to Gen3. + */ + if (dd->pcidev->device == PCI_DEVICE_ID_INTEL1) { /* integrated */ + /* extract initial fields */ + xmt_margin = (pcie_ctrl >> MARGIN_GEN1_GEN2_SHIFT) + & MARGIN_GEN1_GEN2_MASK; + xmt_margin_oe = (pcie_ctrl >> MARGIN_G1_G2_OVERWRITE_SHIFT) + & MARGIN_G1_G2_OVERWRITE_MASK; + lane_delay = (pcie_ctrl >> LANE_DELAY_SHIFT) & LANE_DELAY_MASK; + lane_bundle = (pcie_ctrl >> LANE_BUNDLE_SHIFT) + & LANE_BUNDLE_MASK; + + /* + * For A0, EFUSE values are not set. Override with the + * correct values. + */ + if (is_ax(dd)) { + /* + * xmt_margin and OverwiteEnabel should be the + * same for Gen1/Gen2 and Gen3 + */ + xmt_margin = 0x5; + xmt_margin_oe = 0x1; + lane_delay = 0xF; /* Delay 240ns. */ + lane_bundle = 0x0; /* Set to 1 lane. */ + } + + /* overwrite existing values */ + pcie_ctrl = (xmt_margin << MARGIN_GEN1_GEN2_SHIFT) + | (xmt_margin_oe << MARGIN_G1_G2_OVERWRITE_SHIFT) + | (xmt_margin << MARGIN_SHIFT) + | (xmt_margin_oe << MARGIN_OVERWRITE_ENABLE_SHIFT) + | (lane_delay << LANE_DELAY_SHIFT) + | (lane_bundle << LANE_BUNDLE_SHIFT); + + write_csr(dd, CCE_PCIE_CTRL, pcie_ctrl); + } + + dd_dev_dbg(dd, "%s: program XMT margin, CcePcieCtrl 0x%llx\n", + fname, pcie_ctrl); +} + +/* + * Do all the steps needed to transition the PCIe link to Gen3 speed. + */ +int do_pcie_gen3_transition(struct hfi1_devdata *dd) +{ + struct pci_dev *parent = dd->pcidev->bus->self; + u64 fw_ctrl; + u64 reg, therm; + u32 reg32, fs, lf; + u32 status, err; + int ret; + int do_retry, retry_count = 0; + int intnum = 0; + uint default_pset; + uint pset = pcie_pset; + u16 target_vector, target_speed; + u16 lnkctl2, vendor; + u8 div; + const u8 (*eq)[3]; + const u8 (*ctle_tunings)[4]; + uint static_ctle_mode; + int return_error = 0; + + /* PCIe Gen3 is for the ASIC only */ + if (dd->icode != ICODE_RTL_SILICON) + return 0; + + if (pcie_target == 1) { /* target Gen1 */ + target_vector = PCI_EXP_LNKCTL2_TLS_2_5GT; + target_speed = 2500; + } else if (pcie_target == 2) { /* target Gen2 */ + target_vector = PCI_EXP_LNKCTL2_TLS_5_0GT; + target_speed = 5000; + } else if (pcie_target == 3) { /* target Gen3 */ + target_vector = PCI_EXP_LNKCTL2_TLS_8_0GT; + target_speed = 8000; + } else { + /* off or invalid target - skip */ + dd_dev_info(dd, "%s: Skipping PCIe transition\n", __func__); + return 0; + } + + /* if already at target speed, done (unless forced) */ + if (dd->lbus_speed == target_speed) { + dd_dev_info(dd, "%s: PCIe already at gen%d, %s\n", __func__, + pcie_target, + pcie_force ? "re-doing anyway" : "skipping"); + if (!pcie_force) + return 0; + } + + /* + * The driver cannot do the transition if it has no access to the + * upstream component + */ + if (!parent) { + dd_dev_info(dd, "%s: No upstream, Can't do gen3 transition\n", + __func__); + return 0; + } + + /* + * Do the Gen3 transition. Steps are those of the PCIe Gen3 + * recipe. + */ + + /* step 1: pcie link working in gen1/gen2 */ + + /* step 2: if either side is not capable of Gen3, done */ + if (pcie_target == 3 && !dd->link_gen3_capable) { + dd_dev_err(dd, "The PCIe link is not Gen3 capable\n"); + ret = -ENOSYS; + goto done_no_mutex; + } + + /* hold the SBus resource across the firmware download and SBR */ + ret = acquire_chip_resource(dd, CR_SBUS, SBUS_TIMEOUT); + if (ret) { + dd_dev_err(dd, "%s: unable to acquire SBus resource\n", + __func__); + return ret; + } + + /* make sure thermal polling is not causing interrupts */ + therm = read_csr(dd, ASIC_CFG_THERM_POLL_EN); + if (therm) { + write_csr(dd, ASIC_CFG_THERM_POLL_EN, 0x0); + msleep(100); + dd_dev_info(dd, "%s: Disabled therm polling\n", + __func__); + } + +retry: + /* the SBus download will reset the spico for thermal */ + + /* step 3: download SBus Master firmware */ + /* step 4: download PCIe Gen3 SerDes firmware */ + dd_dev_info(dd, "%s: downloading firmware\n", __func__); + ret = load_pcie_firmware(dd); + if (ret) { + /* do not proceed if the firmware cannot be downloaded */ + return_error = 1; + goto done; + } + + /* step 5: set up device parameter settings */ + dd_dev_info(dd, "%s: setting PCIe registers\n", __func__); + + /* + * PcieCfgSpcie1 - Link Control 3 + * Leave at reset value. No need to set PerfEq - link equalization + * will be performed automatically after the SBR when the target + * speed is 8GT/s. + */ + + /* clear all 16 per-lane error bits (PCIe: Lane Error Status) */ + pci_write_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, 0xffff); + + /* step 5a: Set Synopsys Port Logic registers */ + + /* + * PcieCfgRegPl2 - Port Force Link + * + * Set the low power field to 0x10 to avoid unnecessary power + * management messages. All other fields are zero. + */ + reg32 = 0x10ul << PCIE_CFG_REG_PL2_LOW_PWR_ENT_CNT_SHIFT; + pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL2, reg32); + + /* + * PcieCfgRegPl100 - Gen3 Control + * + * turn off PcieCfgRegPl100.Gen3ZRxDcNonCompl + * turn on PcieCfgRegPl100.EqEieosCnt + * Everything else zero. + */ + reg32 = PCIE_CFG_REG_PL100_EQ_EIEOS_CNT_SMASK; + pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL100, reg32); + + /* + * PcieCfgRegPl101 - Gen3 EQ FS and LF + * PcieCfgRegPl102 - Gen3 EQ Presets to Coefficients Mapping + * PcieCfgRegPl103 - Gen3 EQ Preset Index + * PcieCfgRegPl105 - Gen3 EQ Status + * + * Give initial EQ settings. + */ + if (dd->pcidev->device == PCI_DEVICE_ID_INTEL0) { /* discrete */ + /* 1000mV, FS=24, LF = 8 */ + fs = 24; + lf = 8; + div = 3; + eq = discrete_preliminary_eq; + default_pset = DEFAULT_DISCRETE_PSET; + ctle_tunings = discrete_ctle_tunings; + /* bit 0 - discrete on/off */ + static_ctle_mode = pcie_ctle & 0x1; + } else { + /* 400mV, FS=29, LF = 9 */ + fs = 29; + lf = 9; + div = 1; + eq = integrated_preliminary_eq; + default_pset = DEFAULT_MCP_PSET; + ctle_tunings = integrated_ctle_tunings; + /* bit 1 - integrated on/off */ + static_ctle_mode = (pcie_ctle >> 1) & 0x1; + } + pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL101, + (fs << + PCIE_CFG_REG_PL101_GEN3_EQ_LOCAL_FS_SHIFT) | + (lf << + PCIE_CFG_REG_PL101_GEN3_EQ_LOCAL_LF_SHIFT)); + ret = load_eq_table(dd, eq, fs, div); + if (ret) + goto done; + + /* + * PcieCfgRegPl106 - Gen3 EQ Control + * + * Set Gen3EqPsetReqVec, leave other fields 0. + */ + if (pset == UNSET_PSET) + pset = default_pset; + if (pset > 10) { /* valid range is 0-10, inclusive */ + dd_dev_err(dd, "%s: Invalid Eq Pset %u, setting to %d\n", + __func__, pset, default_pset); + pset = default_pset; + } + dd_dev_info(dd, "%s: using EQ Pset %u\n", __func__, pset); + pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL106, + ((1 << pset) << + PCIE_CFG_REG_PL106_GEN3_EQ_PSET_REQ_VEC_SHIFT) | + PCIE_CFG_REG_PL106_GEN3_EQ_EVAL2MS_DISABLE_SMASK | + PCIE_CFG_REG_PL106_GEN3_EQ_PHASE23_EXIT_MODE_SMASK); + + /* + * step 5b: Do post firmware download steps via SBus + */ + dd_dev_info(dd, "%s: doing pcie post steps\n", __func__); + pcie_post_steps(dd); + + /* + * step 5c: Program gasket interrupts + */ + /* set the Rx Bit Rate to REFCLK ratio */ + write_gasket_interrupt(dd, intnum++, 0x0006, 0x0050); + /* disable pCal for PCIe Gen3 RX equalization */ + /* select adaptive or static CTLE */ + write_gasket_interrupt(dd, intnum++, 0x0026, + 0x5b01 | (static_ctle_mode << 3)); + /* + * Enable iCal for PCIe Gen3 RX equalization, and set which + * evaluation of RX_EQ_EVAL will launch the iCal procedure. + */ + write_gasket_interrupt(dd, intnum++, 0x0026, 0x5202); + + if (static_ctle_mode) { + /* apply static CTLE tunings */ + u8 pcie_dc, pcie_lf, pcie_hf, pcie_bw; + + pcie_dc = ctle_tunings[pset][0]; + pcie_lf = ctle_tunings[pset][1]; + pcie_hf = ctle_tunings[pset][2]; + pcie_bw = ctle_tunings[pset][3]; + write_gasket_interrupt(dd, intnum++, 0x0026, 0x0200 | pcie_dc); + write_gasket_interrupt(dd, intnum++, 0x0026, 0x0100 | pcie_lf); + write_gasket_interrupt(dd, intnum++, 0x0026, 0x0000 | pcie_hf); + write_gasket_interrupt(dd, intnum++, 0x0026, 0x5500 | pcie_bw); + } + + /* terminate list */ + write_gasket_interrupt(dd, intnum++, 0x0000, 0x0000); + + /* + * step 5d: program XMT margin + */ + write_xmt_margin(dd, __func__); + + /* + * step 5e: disable active state power management (ASPM). It + * will be enabled if required later + */ + dd_dev_info(dd, "%s: clearing ASPM\n", __func__); + aspm_hw_disable_l1(dd); + + /* + * step 5f: clear DirectSpeedChange + * PcieCfgRegPl67.DirectSpeedChange must be zero to prevent the + * change in the speed target from starting before we are ready. + * This field defaults to 0 and we are not changing it, so nothing + * needs to be done. + */ + + /* step 5g: Set target link speed */ + /* + * Set target link speed to be target on both device and parent. + * On setting the parent: Some system BIOSs "helpfully" set the + * parent target speed to Gen2 to match the ASIC's initial speed. + * We can set the target Gen3 because we have already checked + * that it is Gen3 capable earlier. + */ + dd_dev_info(dd, "%s: setting parent target link speed\n", __func__); + ret = pcie_capability_read_word(parent, PCI_EXP_LNKCTL2, &lnkctl2); + if (ret) { + dd_dev_err(dd, "Unable to read from PCI config\n"); + return_error = 1; + goto done; + } + + dd_dev_info(dd, "%s: ..old link control2: 0x%x\n", __func__, + (u32)lnkctl2); + /* only write to parent if target is not as high as ours */ + if ((lnkctl2 & PCI_EXP_LNKCTL2_TLS) < target_vector) { + lnkctl2 &= ~PCI_EXP_LNKCTL2_TLS; + lnkctl2 |= target_vector; + dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__, + (u32)lnkctl2); + ret = pcie_capability_write_word(parent, + PCI_EXP_LNKCTL2, lnkctl2); + if (ret) { + dd_dev_err(dd, "Unable to write to PCI config\n"); + return_error = 1; + goto done; + } + } else { + dd_dev_info(dd, "%s: ..target speed is OK\n", __func__); + } + + dd_dev_info(dd, "%s: setting target link speed\n", __func__); + ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL2, &lnkctl2); + if (ret) { + dd_dev_err(dd, "Unable to read from PCI config\n"); + return_error = 1; + goto done; + } + + dd_dev_info(dd, "%s: ..old link control2: 0x%x\n", __func__, + (u32)lnkctl2); + lnkctl2 &= ~PCI_EXP_LNKCTL2_TLS; + lnkctl2 |= target_vector; + dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__, + (u32)lnkctl2); + ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL2, lnkctl2); + if (ret) { + dd_dev_err(dd, "Unable to write to PCI config\n"); + return_error = 1; + goto done; + } + + /* step 5h: arm gasket logic */ + /* hold DC in reset across the SBR */ + write_csr(dd, CCE_DC_CTRL, CCE_DC_CTRL_DC_RESET_SMASK); + (void)read_csr(dd, CCE_DC_CTRL); /* DC reset hold */ + /* save firmware control across the SBR */ + fw_ctrl = read_csr(dd, MISC_CFG_FW_CTRL); + + dd_dev_info(dd, "%s: arming gasket logic\n", __func__); + arm_gasket_logic(dd); + + /* + * step 6: quiesce PCIe link + * The chip has already been reset, so there will be no traffic + * from the chip. Linux has no easy way to enforce that it will + * not try to access the device, so we just need to hope it doesn't + * do it while we are doing the reset. + */ + + /* + * step 7: initiate the secondary bus reset (SBR) + * step 8: hardware brings the links back up + * step 9: wait for link speed transition to be complete + */ + dd_dev_info(dd, "%s: calling trigger_sbr\n", __func__); + ret = trigger_sbr(dd); + if (ret) + goto done; + + /* step 10: decide what to do next */ + + /* check if we can read PCI space */ + ret = pci_read_config_word(dd->pcidev, PCI_VENDOR_ID, &vendor); + if (ret) { + dd_dev_info(dd, + "%s: read of VendorID failed after SBR, err %d\n", + __func__, ret); + return_error = 1; + goto done; + } + if (vendor == 0xffff) { + dd_dev_info(dd, "%s: VendorID is all 1s after SBR\n", __func__); + return_error = 1; + ret = -EIO; + goto done; + } + + /* restore PCI space registers we know were reset */ + dd_dev_info(dd, "%s: calling restore_pci_variables\n", __func__); + ret = restore_pci_variables(dd); + if (ret) { + dd_dev_err(dd, "%s: Could not restore PCI variables\n", + __func__); + return_error = 1; + goto done; + } + + /* restore firmware control */ + write_csr(dd, MISC_CFG_FW_CTRL, fw_ctrl); + + /* + * Check the gasket block status. + * + * This is the first CSR read after the SBR. If the read returns + * all 1s (fails), the link did not make it back. + * + * Once we're sure we can read and write, clear the DC reset after + * the SBR. Then check for any per-lane errors. Then look over + * the status. + */ + reg = read_csr(dd, ASIC_PCIE_SD_HOST_STATUS); + dd_dev_info(dd, "%s: gasket block status: 0x%llx\n", __func__, reg); + if (reg == ~0ull) { /* PCIe read failed/timeout */ + dd_dev_err(dd, "SBR failed - unable to read from device\n"); + return_error = 1; + ret = -ENOSYS; + goto done; + } + + /* clear the DC reset */ + write_csr(dd, CCE_DC_CTRL, 0); + + /* Set the LED off */ + setextled(dd, 0); + + /* check for any per-lane errors */ + ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, ®32); + if (ret) { + dd_dev_err(dd, "Unable to read from PCI config\n"); + return_error = 1; + goto done; + } + + dd_dev_info(dd, "%s: per-lane errors: 0x%x\n", __func__, reg32); + + /* extract status, look for our HFI */ + status = (reg >> ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_STS_SHIFT) + & ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_STS_MASK; + if ((status & (1 << dd->hfi1_id)) == 0) { + dd_dev_err(dd, + "%s: gasket status 0x%x, expecting 0x%x\n", + __func__, status, 1 << dd->hfi1_id); + ret = -EIO; + goto done; + } + + /* extract error */ + err = (reg >> ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_ERR_SHIFT) + & ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_ERR_MASK; + if (err) { + dd_dev_err(dd, "%s: gasket error %d\n", __func__, err); + ret = -EIO; + goto done; + } + + /* update our link information cache */ + update_lbus_info(dd); + dd_dev_info(dd, "%s: new speed and width: %s\n", __func__, + dd->lbus_info); + + if (dd->lbus_speed != target_speed) { /* not target */ + /* maybe retry */ + do_retry = retry_count < pcie_retry; + dd_dev_err(dd, "PCIe link speed did not switch to Gen%d%s\n", + pcie_target, do_retry ? ", retrying" : ""); + retry_count++; + if (do_retry) { + msleep(100); /* allow time to settle */ + goto retry; + } + ret = -EIO; + } + +done: + if (therm) { + write_csr(dd, ASIC_CFG_THERM_POLL_EN, 0x1); + msleep(100); + dd_dev_info(dd, "%s: Re-enable therm polling\n", + __func__); + } + release_chip_resource(dd, CR_SBUS); +done_no_mutex: + /* return no error if it is OK to be at current speed */ + if (ret && !return_error) { + dd_dev_err(dd, "Proceeding at current speed PCIe speed\n"); + ret = 0; + } + + dd_dev_info(dd, "%s: done\n", __func__); + return ret; +} |