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1// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause2/*3 * Copyright(c) 2015 - 2019 Intel Corporation.4 */5 6#include <linux/bitfield.h>7#include <linux/pci.h>8#include <linux/io.h>9#include <linux/delay.h>10#include <linux/vmalloc.h>11#include <linux/module.h>12 13#include "hfi.h"14#include "chip_registers.h"15#include "aspm.h"16 17/*18 * This file contains PCIe utility routines.19 */20 21/*22 * Do all the common PCIe setup and initialization.23 */24int hfi1_pcie_init(struct hfi1_devdata *dd)25{26	int ret;27	struct pci_dev *pdev = dd->pcidev;28 29	ret = pci_enable_device(pdev);30	if (ret) {31		/*32		 * This can happen (in theory) iff:33		 * We did a chip reset, and then failed to reprogram the34		 * BAR, or the chip reset due to an internal error.  We then35		 * unloaded the driver and reloaded it.36		 *37		 * Both reset cases set the BAR back to initial state.  For38		 * the latter case, the AER sticky error bit at offset 0x71839		 * should be set, but the Linux kernel doesn't yet know40		 * about that, it appears.  If the original BAR was retained41		 * in the kernel data structures, this may be OK.42		 */43		dd_dev_err(dd, "pci enable failed: error %d\n", -ret);44		return ret;45	}46 47	ret = pci_request_regions(pdev, DRIVER_NAME);48	if (ret) {49		dd_dev_err(dd, "pci_request_regions fails: err %d\n", -ret);50		goto bail;51	}52 53	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));54	if (ret) {55		/*56		 * If the 64 bit setup fails, try 32 bit.  Some systems57		 * do not setup 64 bit maps on systems with 2GB or less58		 * memory installed.59		 */60		ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));61		if (ret) {62			dd_dev_err(dd, "Unable to set DMA mask: %d\n", ret);63			goto bail;64		}65	}66 67	pci_set_master(pdev);68	return 0;69 70bail:71	hfi1_pcie_cleanup(pdev);72	return ret;73}74 75/*76 * Clean what was done in hfi1_pcie_init()77 */78void hfi1_pcie_cleanup(struct pci_dev *pdev)79{80	pci_disable_device(pdev);81	/*82	 * Release regions should be called after the disable. OK to83	 * call if request regions has not been called or failed.84	 */85	pci_release_regions(pdev);86}87 88/*89 * Do remaining PCIe setup, once dd is allocated, and save away90 * fields required to re-initialize after a chip reset, or for91 * various other purposes92 */93int hfi1_pcie_ddinit(struct hfi1_devdata *dd, struct pci_dev *pdev)94{95	unsigned long len;96	resource_size_t addr;97	int ret = 0;98	u32 rcv_array_count;99 100	addr = pci_resource_start(pdev, 0);101	len = pci_resource_len(pdev, 0);102 103	/*104	 * The TXE PIO buffers are at the tail end of the chip space.105	 * Cut them off and map them separately.106	 */107 108	/* sanity check vs expectations */109	if (len != TXE_PIO_SEND + TXE_PIO_SIZE) {110		dd_dev_err(dd, "chip PIO range does not match\n");111		return -EINVAL;112	}113 114	dd->kregbase1 = ioremap(addr, RCV_ARRAY);115	if (!dd->kregbase1) {116		dd_dev_err(dd, "UC mapping of kregbase1 failed\n");117		return -ENOMEM;118	}119	dd_dev_info(dd, "UC base1: %p for %x\n", dd->kregbase1, RCV_ARRAY);120 121	/* verify that reads actually work, save revision for reset check */122	dd->revision = readq(dd->kregbase1 + CCE_REVISION);123	if (dd->revision == ~(u64)0) {124		dd_dev_err(dd, "Cannot read chip CSRs\n");125		goto nomem;126	}127 128	rcv_array_count = readq(dd->kregbase1 + RCV_ARRAY_CNT);129	dd_dev_info(dd, "RcvArray count: %u\n", rcv_array_count);130	dd->base2_start  = RCV_ARRAY + rcv_array_count * 8;131 132	dd->kregbase2 = ioremap(133		addr + dd->base2_start,134		TXE_PIO_SEND - dd->base2_start);135	if (!dd->kregbase2) {136		dd_dev_err(dd, "UC mapping of kregbase2 failed\n");137		goto nomem;138	}139	dd_dev_info(dd, "UC base2: %p for %x\n", dd->kregbase2,140		    TXE_PIO_SEND - dd->base2_start);141 142	dd->piobase = ioremap_wc(addr + TXE_PIO_SEND, TXE_PIO_SIZE);143	if (!dd->piobase) {144		dd_dev_err(dd, "WC mapping of send buffers failed\n");145		goto nomem;146	}147	dd_dev_info(dd, "WC piobase: %p for %x\n", dd->piobase, TXE_PIO_SIZE);148 149	dd->physaddr = addr;        /* used for io_remap, etc. */150 151	/*152	 * Map the chip's RcvArray as write-combining to allow us153	 * to write an entire cacheline worth of entries in one shot.154	 */155	dd->rcvarray_wc = ioremap_wc(addr + RCV_ARRAY,156				     rcv_array_count * 8);157	if (!dd->rcvarray_wc) {158		dd_dev_err(dd, "WC mapping of receive array failed\n");159		goto nomem;160	}161	dd_dev_info(dd, "WC RcvArray: %p for %x\n",162		    dd->rcvarray_wc, rcv_array_count * 8);163 164	dd->flags |= HFI1_PRESENT;	/* chip.c CSR routines now work */165	return 0;166nomem:167	ret = -ENOMEM;168	hfi1_pcie_ddcleanup(dd);169	return ret;170}171 172/*173 * Do PCIe cleanup related to dd, after chip-specific cleanup, etc.  Just prior174 * to releasing the dd memory.175 * Void because all of the core pcie cleanup functions are void.176 */177void hfi1_pcie_ddcleanup(struct hfi1_devdata *dd)178{179	dd->flags &= ~HFI1_PRESENT;180	if (dd->kregbase1)181		iounmap(dd->kregbase1);182	dd->kregbase1 = NULL;183	if (dd->kregbase2)184		iounmap(dd->kregbase2);185	dd->kregbase2 = NULL;186	if (dd->rcvarray_wc)187		iounmap(dd->rcvarray_wc);188	dd->rcvarray_wc = NULL;189	if (dd->piobase)190		iounmap(dd->piobase);191	dd->piobase = NULL;192}193 194/* return the PCIe link speed from the given link status */195static u32 extract_speed(u16 linkstat)196{197	u32 speed;198 199	switch (linkstat & PCI_EXP_LNKSTA_CLS) {200	default: /* not defined, assume Gen1 */201	case PCI_EXP_LNKSTA_CLS_2_5GB:202		speed = 2500; /* Gen 1, 2.5GHz */203		break;204	case PCI_EXP_LNKSTA_CLS_5_0GB:205		speed = 5000; /* Gen 2, 5GHz */206		break;207	case PCI_EXP_LNKSTA_CLS_8_0GB:208		speed = 8000; /* Gen 3, 8GHz */209		break;210	}211	return speed;212}213 214/* read the link status and set dd->{lbus_width,lbus_speed,lbus_info} */215static void update_lbus_info(struct hfi1_devdata *dd)216{217	u16 linkstat;218	int ret;219 220	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKSTA, &linkstat);221	if (ret) {222		dd_dev_err(dd, "Unable to read from PCI config\n");223		return;224	}225 226	dd->lbus_width = FIELD_GET(PCI_EXP_LNKSTA_NLW, linkstat);227	dd->lbus_speed = extract_speed(linkstat);228	snprintf(dd->lbus_info, sizeof(dd->lbus_info),229		 "PCIe,%uMHz,x%u", dd->lbus_speed, dd->lbus_width);230}231 232/*233 * Read in the current PCIe link width and speed.  Find if the link is234 * Gen3 capable.235 */236int pcie_speeds(struct hfi1_devdata *dd)237{238	u32 linkcap;239	struct pci_dev *parent = dd->pcidev->bus->self;240	int ret;241 242	if (!pci_is_pcie(dd->pcidev)) {243		dd_dev_err(dd, "Can't find PCI Express capability!\n");244		return -EINVAL;245	}246 247	/* find if our max speed is Gen3 and parent supports Gen3 speeds */248	dd->link_gen3_capable = 1;249 250	ret = pcie_capability_read_dword(dd->pcidev, PCI_EXP_LNKCAP, &linkcap);251	if (ret) {252		dd_dev_err(dd, "Unable to read from PCI config\n");253		return pcibios_err_to_errno(ret);254	}255 256	if ((linkcap & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_8_0GB) {257		dd_dev_info(dd,258			    "This HFI is not Gen3 capable, max speed 0x%x, need 0x3\n",259			    linkcap & PCI_EXP_LNKCAP_SLS);260		dd->link_gen3_capable = 0;261	}262 263	/*264	 * bus->max_bus_speed is set from the bridge's linkcap Max Link Speed265	 */266	if (parent &&267	    (dd->pcidev->bus->max_bus_speed == PCIE_SPEED_2_5GT ||268	     dd->pcidev->bus->max_bus_speed == PCIE_SPEED_5_0GT)) {269		dd_dev_info(dd, "Parent PCIe bridge does not support Gen3\n");270		dd->link_gen3_capable = 0;271	}272 273	/* obtain the link width and current speed */274	update_lbus_info(dd);275 276	dd_dev_info(dd, "%s\n", dd->lbus_info);277 278	return 0;279}280 281/*282 * Restore command and BARs after a reset has wiped them out283 *284 * Returns 0 on success, otherwise a negative error value285 */286int restore_pci_variables(struct hfi1_devdata *dd)287{288	int ret;289 290	ret = pci_write_config_word(dd->pcidev, PCI_COMMAND, dd->pci_command);291	if (ret)292		goto error;293 294	ret = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0,295				     dd->pcibar0);296	if (ret)297		goto error;298 299	ret = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1,300				     dd->pcibar1);301	if (ret)302		goto error;303 304	ret = pci_write_config_dword(dd->pcidev, PCI_ROM_ADDRESS, dd->pci_rom);305	if (ret)306		goto error;307 308	ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL,309					 dd->pcie_devctl);310	if (ret)311		goto error;312 313	ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL,314					 dd->pcie_lnkctl);315	if (ret)316		goto error;317 318	ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL2,319					 dd->pcie_devctl2);320	if (ret)321		goto error;322 323	ret = pci_write_config_dword(dd->pcidev, PCI_CFG_MSIX0, dd->pci_msix0);324	if (ret)325		goto error;326 327	if (pci_find_ext_capability(dd->pcidev, PCI_EXT_CAP_ID_TPH)) {328		ret = pci_write_config_dword(dd->pcidev, PCIE_CFG_TPH2,329					     dd->pci_tph2);330		if (ret)331			goto error;332	}333	return 0;334 335error:336	dd_dev_err(dd, "Unable to write to PCI config\n");337	return pcibios_err_to_errno(ret);338}339 340/*341 * Save BARs and command to rewrite after device reset342 *343 * Returns 0 on success, otherwise a negative error value344 */345int save_pci_variables(struct hfi1_devdata *dd)346{347	int ret;348 349	ret = pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0,350				    &dd->pcibar0);351	if (ret)352		goto error;353 354	ret = pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1,355				    &dd->pcibar1);356	if (ret)357		goto error;358 359	ret = pci_read_config_dword(dd->pcidev, PCI_ROM_ADDRESS, &dd->pci_rom);360	if (ret)361		goto error;362 363	ret = pci_read_config_word(dd->pcidev, PCI_COMMAND, &dd->pci_command);364	if (ret)365		goto error;366 367	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL,368					&dd->pcie_devctl);369	if (ret)370		goto error;371 372	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL,373					&dd->pcie_lnkctl);374	if (ret)375		goto error;376 377	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL2,378					&dd->pcie_devctl2);379	if (ret)380		goto error;381 382	ret = pci_read_config_dword(dd->pcidev, PCI_CFG_MSIX0, &dd->pci_msix0);383	if (ret)384		goto error;385 386	if (pci_find_ext_capability(dd->pcidev, PCI_EXT_CAP_ID_TPH)) {387		ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_TPH2,388					    &dd->pci_tph2);389		if (ret)390			goto error;391	}392	return 0;393 394error:395	dd_dev_err(dd, "Unable to read from PCI config\n");396	return pcibios_err_to_errno(ret);397}398 399/*400 * BIOS may not set PCIe bus-utilization parameters for best performance.401 * Check and optionally adjust them to maximize our throughput.402 */403static int hfi1_pcie_caps;404module_param_named(pcie_caps, hfi1_pcie_caps, int, 0444);405MODULE_PARM_DESC(pcie_caps, "Max PCIe tuning: Payload (0..3), ReadReq (4..7)");406 407/**408 * tune_pcie_caps() - Code to adjust PCIe capabilities.409 * @dd: Valid device data structure410 *411 */412void tune_pcie_caps(struct hfi1_devdata *dd)413{414	struct pci_dev *parent;415	u16 rc_mpss, rc_mps, ep_mpss, ep_mps;416	u16 rc_mrrs, ep_mrrs, max_mrrs, ectl;417	int ret;418 419	/*420	 * Turn on extended tags in DevCtl in case the BIOS has turned it off421	 * to improve WFR SDMA bandwidth422	 */423	ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL, &ectl);424	if ((!ret) && !(ectl & PCI_EXP_DEVCTL_EXT_TAG)) {425		dd_dev_info(dd, "Enabling PCIe extended tags\n");426		ectl |= PCI_EXP_DEVCTL_EXT_TAG;427		ret = pcie_capability_write_word(dd->pcidev,428						 PCI_EXP_DEVCTL, ectl);429		if (ret)430			dd_dev_info(dd, "Unable to write to PCI config\n");431	}432	/* Find out supported and configured values for parent (root) */433	parent = dd->pcidev->bus->self;434	/*435	 * The driver cannot perform the tuning if it does not have436	 * access to the upstream component.437	 */438	if (!parent) {439		dd_dev_info(dd, "Parent not found\n");440		return;441	}442	if (!pci_is_root_bus(parent->bus)) {443		dd_dev_info(dd, "Parent not root\n");444		return;445	}446	if (!pci_is_pcie(parent)) {447		dd_dev_info(dd, "Parent is not PCI Express capable\n");448		return;449	}450	if (!pci_is_pcie(dd->pcidev)) {451		dd_dev_info(dd, "PCI device is not PCI Express capable\n");452		return;453	}454	rc_mpss = parent->pcie_mpss;455	rc_mps = ffs(pcie_get_mps(parent)) - 8;456	/* Find out supported and configured values for endpoint (us) */457	ep_mpss = dd->pcidev->pcie_mpss;458	ep_mps = ffs(pcie_get_mps(dd->pcidev)) - 8;459 460	/* Find max payload supported by root, endpoint */461	if (rc_mpss > ep_mpss)462		rc_mpss = ep_mpss;463 464	/* If Supported greater than limit in module param, limit it */465	if (rc_mpss > (hfi1_pcie_caps & 7))466		rc_mpss = hfi1_pcie_caps & 7;467	/* If less than (allowed, supported), bump root payload */468	if (rc_mpss > rc_mps) {469		rc_mps = rc_mpss;470		pcie_set_mps(parent, 128 << rc_mps);471	}472	/* If less than (allowed, supported), bump endpoint payload */473	if (rc_mpss > ep_mps) {474		ep_mps = rc_mpss;475		pcie_set_mps(dd->pcidev, 128 << ep_mps);476	}477 478	/*479	 * Now the Read Request size.480	 * No field for max supported, but PCIe spec limits it to 4096,481	 * which is code '5' (log2(4096) - 7)482	 */483	max_mrrs = 5;484	if (max_mrrs > ((hfi1_pcie_caps >> 4) & 7))485		max_mrrs = (hfi1_pcie_caps >> 4) & 7;486 487	max_mrrs = 128 << max_mrrs;488	rc_mrrs = pcie_get_readrq(parent);489	ep_mrrs = pcie_get_readrq(dd->pcidev);490 491	if (max_mrrs > rc_mrrs) {492		rc_mrrs = max_mrrs;493		pcie_set_readrq(parent, rc_mrrs);494	}495	if (max_mrrs > ep_mrrs) {496		ep_mrrs = max_mrrs;497		pcie_set_readrq(dd->pcidev, ep_mrrs);498	}499}500 501/* End of PCIe capability tuning */502 503/*504 * From here through hfi1_pci_err_handler definition is invoked via505 * PCI error infrastructure, registered via pci506 */507static pci_ers_result_t508pci_error_detected(struct pci_dev *pdev, pci_channel_state_t state)509{510	struct hfi1_devdata *dd = pci_get_drvdata(pdev);511	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;512 513	switch (state) {514	case pci_channel_io_normal:515		dd_dev_info(dd, "State Normal, ignoring\n");516		break;517 518	case pci_channel_io_frozen:519		dd_dev_info(dd, "State Frozen, requesting reset\n");520		pci_disable_device(pdev);521		ret = PCI_ERS_RESULT_NEED_RESET;522		break;523 524	case pci_channel_io_perm_failure:525		if (dd) {526			dd_dev_info(dd, "State Permanent Failure, disabling\n");527			/* no more register accesses! */528			dd->flags &= ~HFI1_PRESENT;529			hfi1_disable_after_error(dd);530		}531		 /* else early, or other problem */532		ret =  PCI_ERS_RESULT_DISCONNECT;533		break;534 535	default: /* shouldn't happen */536		dd_dev_info(dd, "HFI1 PCI errors detected (state %d)\n",537			    state);538		break;539	}540	return ret;541}542 543static pci_ers_result_t544pci_mmio_enabled(struct pci_dev *pdev)545{546	u64 words = 0U;547	struct hfi1_devdata *dd = pci_get_drvdata(pdev);548	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;549 550	if (dd && dd->pport) {551		words = read_port_cntr(dd->pport, C_RX_WORDS, CNTR_INVALID_VL);552		if (words == ~0ULL)553			ret = PCI_ERS_RESULT_NEED_RESET;554		dd_dev_info(dd,555			    "HFI1 mmio_enabled function called, read wordscntr %llx, returning %d\n",556			    words, ret);557	}558	return  ret;559}560 561static pci_ers_result_t562pci_slot_reset(struct pci_dev *pdev)563{564	struct hfi1_devdata *dd = pci_get_drvdata(pdev);565 566	dd_dev_info(dd, "HFI1 slot_reset function called, ignored\n");567	return PCI_ERS_RESULT_CAN_RECOVER;568}569 570static void571pci_resume(struct pci_dev *pdev)572{573	struct hfi1_devdata *dd = pci_get_drvdata(pdev);574 575	dd_dev_info(dd, "HFI1 resume function called\n");576	/*577	 * Running jobs will fail, since it's asynchronous578	 * unlike sysfs-requested reset.   Better than579	 * doing nothing.580	 */581	hfi1_init(dd, 1); /* same as re-init after reset */582}583 584const struct pci_error_handlers hfi1_pci_err_handler = {585	.error_detected = pci_error_detected,586	.mmio_enabled = pci_mmio_enabled,587	.slot_reset = pci_slot_reset,588	.resume = pci_resume,589};590 591/*============================================================================*/592/* PCIe Gen3 support */593 594/*595 * This code is separated out because it is expected to be removed in the596 * final shipping product.  If not, then it will be revisited and items597 * will be moved to more standard locations.598 */599 600/* ASIC_PCI_SD_HOST_STATUS.FW_DNLD_STS field values */601#define DL_STATUS_HFI0 0x1	/* hfi0 firmware download complete */602#define DL_STATUS_HFI1 0x2	/* hfi1 firmware download complete */603#define DL_STATUS_BOTH 0x3	/* hfi0 and hfi1 firmware download complete */604 605/* ASIC_PCI_SD_HOST_STATUS.FW_DNLD_ERR field values */606#define DL_ERR_NONE		0x0	/* no error */607#define DL_ERR_SWAP_PARITY	0x1	/* parity error in SerDes interrupt */608					/*   or response data */609#define DL_ERR_DISABLED	0x2	/* hfi disabled */610#define DL_ERR_SECURITY	0x3	/* security check failed */611#define DL_ERR_SBUS		0x4	/* SBus status error */612#define DL_ERR_XFR_PARITY	0x5	/* parity error during ROM transfer*/613 614/* gasket block secondary bus reset delay */615#define SBR_DELAY_US 200000	/* 200ms */616 617static uint pcie_target = 3;618module_param(pcie_target, uint, S_IRUGO);619MODULE_PARM_DESC(pcie_target, "PCIe target speed (0 skip, 1-3 Gen1-3)");620 621static uint pcie_force;622module_param(pcie_force, uint, S_IRUGO);623MODULE_PARM_DESC(pcie_force, "Force driver to do a PCIe firmware download even if already at target speed");624 625static uint pcie_retry = 5;626module_param(pcie_retry, uint, S_IRUGO);627MODULE_PARM_DESC(pcie_retry, "Driver will try this many times to reach requested speed");628 629#define UNSET_PSET 255630#define DEFAULT_DISCRETE_PSET 2	/* discrete HFI */631#define DEFAULT_MCP_PSET 6	/* MCP HFI */632static uint pcie_pset = UNSET_PSET;633module_param(pcie_pset, uint, S_IRUGO);634MODULE_PARM_DESC(pcie_pset, "PCIe Eq Pset value to use, range is 0-10");635 636static uint pcie_ctle = 3; /* discrete on, integrated on */637module_param(pcie_ctle, uint, S_IRUGO);638MODULE_PARM_DESC(pcie_ctle, "PCIe static CTLE mode, bit 0 - discrete on/off, bit 1 - integrated on/off");639 640/* equalization columns */641#define PREC 0642#define ATTN 1643#define POST 2644 645/* discrete silicon preliminary equalization values */646static const u8 discrete_preliminary_eq[11][3] = {647	/* prec   attn   post */648	{  0x00,  0x00,  0x12 },	/* p0 */649	{  0x00,  0x00,  0x0c },	/* p1 */650	{  0x00,  0x00,  0x0f },	/* p2 */651	{  0x00,  0x00,  0x09 },	/* p3 */652	{  0x00,  0x00,  0x00 },	/* p4 */653	{  0x06,  0x00,  0x00 },	/* p5 */654	{  0x09,  0x00,  0x00 },	/* p6 */655	{  0x06,  0x00,  0x0f },	/* p7 */656	{  0x09,  0x00,  0x09 },	/* p8 */657	{  0x0c,  0x00,  0x00 },	/* p9 */658	{  0x00,  0x00,  0x18 },	/* p10 */659};660 661/* integrated silicon preliminary equalization values */662static const u8 integrated_preliminary_eq[11][3] = {663	/* prec   attn   post */664	{  0x00,  0x1e,  0x07 },	/* p0 */665	{  0x00,  0x1e,  0x05 },	/* p1 */666	{  0x00,  0x1e,  0x06 },	/* p2 */667	{  0x00,  0x1e,  0x04 },	/* p3 */668	{  0x00,  0x1e,  0x00 },	/* p4 */669	{  0x03,  0x1e,  0x00 },	/* p5 */670	{  0x04,  0x1e,  0x00 },	/* p6 */671	{  0x03,  0x1e,  0x06 },	/* p7 */672	{  0x03,  0x1e,  0x04 },	/* p8 */673	{  0x05,  0x1e,  0x00 },	/* p9 */674	{  0x00,  0x1e,  0x0a },	/* p10 */675};676 677static const u8 discrete_ctle_tunings[11][4] = {678	/* DC     LF     HF     BW */679	{  0x48,  0x0b,  0x04,  0x04 },	/* p0 */680	{  0x60,  0x05,  0x0f,  0x0a },	/* p1 */681	{  0x50,  0x09,  0x06,  0x06 },	/* p2 */682	{  0x68,  0x05,  0x0f,  0x0a },	/* p3 */683	{  0x80,  0x05,  0x0f,  0x0a },	/* p4 */684	{  0x70,  0x05,  0x0f,  0x0a },	/* p5 */685	{  0x68,  0x05,  0x0f,  0x0a },	/* p6 */686	{  0x38,  0x0f,  0x00,  0x00 },	/* p7 */687	{  0x48,  0x09,  0x06,  0x06 },	/* p8 */688	{  0x60,  0x05,  0x0f,  0x0a },	/* p9 */689	{  0x38,  0x0f,  0x00,  0x00 },	/* p10 */690};691 692static const u8 integrated_ctle_tunings[11][4] = {693	/* DC     LF     HF     BW */694	{  0x38,  0x0f,  0x00,  0x00 },	/* p0 */695	{  0x38,  0x0f,  0x00,  0x00 },	/* p1 */696	{  0x38,  0x0f,  0x00,  0x00 },	/* p2 */697	{  0x38,  0x0f,  0x00,  0x00 },	/* p3 */698	{  0x58,  0x0a,  0x05,  0x05 },	/* p4 */699	{  0x48,  0x0a,  0x05,  0x05 },	/* p5 */700	{  0x40,  0x0a,  0x05,  0x05 },	/* p6 */701	{  0x38,  0x0f,  0x00,  0x00 },	/* p7 */702	{  0x38,  0x0f,  0x00,  0x00 },	/* p8 */703	{  0x38,  0x09,  0x06,  0x06 },	/* p9 */704	{  0x38,  0x0e,  0x01,  0x01 },	/* p10 */705};706 707/* helper to format the value to write to hardware */708#define eq_value(pre, curr, post) \709	((((u32)(pre)) << \710			PCIE_CFG_REG_PL102_GEN3_EQ_PRE_CURSOR_PSET_SHIFT) \711	| (((u32)(curr)) << PCIE_CFG_REG_PL102_GEN3_EQ_CURSOR_PSET_SHIFT) \712	| (((u32)(post)) << \713		PCIE_CFG_REG_PL102_GEN3_EQ_POST_CURSOR_PSET_SHIFT))714 715/*716 * Load the given EQ preset table into the PCIe hardware.717 */718static int load_eq_table(struct hfi1_devdata *dd, const u8 eq[11][3], u8 fs,719			 u8 div)720{721	struct pci_dev *pdev = dd->pcidev;722	u32 hit_error = 0;723	u32 violation;724	u32 i;725	u8 c_minus1, c0, c_plus1;726	int ret;727 728	for (i = 0; i < 11; i++) {729		/* set index */730		pci_write_config_dword(pdev, PCIE_CFG_REG_PL103, i);731		/* write the value */732		c_minus1 = eq[i][PREC] / div;733		c0 = fs - (eq[i][PREC] / div) - (eq[i][POST] / div);734		c_plus1 = eq[i][POST] / div;735		pci_write_config_dword(pdev, PCIE_CFG_REG_PL102,736				       eq_value(c_minus1, c0, c_plus1));737		/* check if these coefficients violate EQ rules */738		ret = pci_read_config_dword(dd->pcidev,739					    PCIE_CFG_REG_PL105, &violation);740		if (ret) {741			dd_dev_err(dd, "Unable to read from PCI config\n");742			hit_error = 1;743			break;744		}745 746		if (violation747		    & PCIE_CFG_REG_PL105_GEN3_EQ_VIOLATE_COEF_RULES_SMASK){748			if (hit_error == 0) {749				dd_dev_err(dd,750					   "Gen3 EQ Table Coefficient rule violations\n");751				dd_dev_err(dd, "         prec   attn   post\n");752			}753			dd_dev_err(dd, "   p%02d:   %02x     %02x     %02x\n",754				   i, (u32)eq[i][0], (u32)eq[i][1],755				   (u32)eq[i][2]);756			dd_dev_err(dd, "            %02x     %02x     %02x\n",757				   (u32)c_minus1, (u32)c0, (u32)c_plus1);758			hit_error = 1;759		}760	}761	if (hit_error)762		return -EINVAL;763	return 0;764}765 766/*767 * Steps to be done after the PCIe firmware is downloaded and768 * before the SBR for the Pcie Gen3.769 * The SBus resource is already being held.770 */771static void pcie_post_steps(struct hfi1_devdata *dd)772{773	int i;774 775	set_sbus_fast_mode(dd);776	/*777	 * Write to the PCIe PCSes to set the G3_LOCKED_NEXT bits to 1.778	 * This avoids a spurious framing error that can otherwise be779	 * generated by the MAC layer.780	 *781	 * Use individual addresses since no broadcast is set up.782	 */783	for (i = 0; i < NUM_PCIE_SERDES; i++) {784		sbus_request(dd, pcie_pcs_addrs[dd->hfi1_id][i],785			     0x03, WRITE_SBUS_RECEIVER, 0x00022132);786	}787 788	clear_sbus_fast_mode(dd);789}790 791/*792 * Trigger a secondary bus reset (SBR) on ourselves using our parent.793 *794 * Based on pci_parent_bus_reset() which is not exported by the795 * kernel core.796 */797static int trigger_sbr(struct hfi1_devdata *dd)798{799	struct pci_dev *dev = dd->pcidev;800	struct pci_dev *pdev;801 802	/* need a parent */803	if (!dev->bus->self) {804		dd_dev_err(dd, "%s: no parent device\n", __func__);805		return -ENOTTY;806	}807 808	/* should not be anyone else on the bus */809	list_for_each_entry(pdev, &dev->bus->devices, bus_list)810		if (pdev != dev) {811			dd_dev_err(dd,812				   "%s: another device is on the same bus\n",813				   __func__);814			return -ENOTTY;815		}816 817	/*818	 * This is an end around to do an SBR during probe time. A new API needs819	 * to be implemented to have cleaner interface but this fixes the820	 * current brokenness821	 */822	return pci_bridge_secondary_bus_reset(dev->bus->self);823}824 825/*826 * Write the given gasket interrupt register.827 */828static void write_gasket_interrupt(struct hfi1_devdata *dd, int index,829				   u16 code, u16 data)830{831	write_csr(dd, ASIC_PCIE_SD_INTRPT_LIST + (index * 8),832		  (((u64)code << ASIC_PCIE_SD_INTRPT_LIST_INTRPT_CODE_SHIFT) |833		   ((u64)data << ASIC_PCIE_SD_INTRPT_LIST_INTRPT_DATA_SHIFT)));834}835 836/*837 * Tell the gasket logic how to react to the reset.838 */839static void arm_gasket_logic(struct hfi1_devdata *dd)840{841	u64 reg;842 843	reg = (((u64)1 << dd->hfi1_id) <<844	       ASIC_PCIE_SD_HOST_CMD_INTRPT_CMD_SHIFT) |845	      ((u64)pcie_serdes_broadcast[dd->hfi1_id] <<846	       ASIC_PCIE_SD_HOST_CMD_SBUS_RCVR_ADDR_SHIFT |847	       ASIC_PCIE_SD_HOST_CMD_SBR_MODE_SMASK |848	       ((u64)SBR_DELAY_US & ASIC_PCIE_SD_HOST_CMD_TIMER_MASK) <<849	       ASIC_PCIE_SD_HOST_CMD_TIMER_SHIFT);850	write_csr(dd, ASIC_PCIE_SD_HOST_CMD, reg);851	/* read back to push the write */852	read_csr(dd, ASIC_PCIE_SD_HOST_CMD);853}854 855/*856 * CCE_PCIE_CTRL long name helpers857 * We redefine these shorter macros to use in the code while leaving858 * chip_registers.h to be autogenerated from the hardware spec.859 */860#define LANE_BUNDLE_MASK              CCE_PCIE_CTRL_PCIE_LANE_BUNDLE_MASK861#define LANE_BUNDLE_SHIFT             CCE_PCIE_CTRL_PCIE_LANE_BUNDLE_SHIFT862#define LANE_DELAY_MASK               CCE_PCIE_CTRL_PCIE_LANE_DELAY_MASK863#define LANE_DELAY_SHIFT              CCE_PCIE_CTRL_PCIE_LANE_DELAY_SHIFT864#define MARGIN_OVERWRITE_ENABLE_SHIFT CCE_PCIE_CTRL_XMT_MARGIN_OVERWRITE_ENABLE_SHIFT865#define MARGIN_SHIFT                  CCE_PCIE_CTRL_XMT_MARGIN_SHIFT866#define MARGIN_G1_G2_OVERWRITE_MASK   CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_OVERWRITE_ENABLE_MASK867#define MARGIN_G1_G2_OVERWRITE_SHIFT  CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_OVERWRITE_ENABLE_SHIFT868#define MARGIN_GEN1_GEN2_MASK         CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_MASK869#define MARGIN_GEN1_GEN2_SHIFT        CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_SHIFT870 871 /*872  * Write xmt_margin for full-swing (WFR-B) or half-swing (WFR-C).873  */874static void write_xmt_margin(struct hfi1_devdata *dd, const char *fname)875{876	u64 pcie_ctrl;877	u64 xmt_margin;878	u64 xmt_margin_oe;879	u64 lane_delay;880	u64 lane_bundle;881 882	pcie_ctrl = read_csr(dd, CCE_PCIE_CTRL);883 884	/*885	 * For Discrete, use full-swing.886	 *  - PCIe TX defaults to full-swing.887	 *    Leave this register as default.888	 * For Integrated, use half-swing889	 *  - Copy xmt_margin and xmt_margin_oe890	 *    from Gen1/Gen2 to Gen3.891	 */892	if (dd->pcidev->device == PCI_DEVICE_ID_INTEL1) { /* integrated */893		/* extract initial fields */894		xmt_margin = (pcie_ctrl >> MARGIN_GEN1_GEN2_SHIFT)895			      & MARGIN_GEN1_GEN2_MASK;896		xmt_margin_oe = (pcie_ctrl >> MARGIN_G1_G2_OVERWRITE_SHIFT)897				 & MARGIN_G1_G2_OVERWRITE_MASK;898		lane_delay = (pcie_ctrl >> LANE_DELAY_SHIFT) & LANE_DELAY_MASK;899		lane_bundle = (pcie_ctrl >> LANE_BUNDLE_SHIFT)900			       & LANE_BUNDLE_MASK;901 902		/*903		 * For A0, EFUSE values are not set.  Override with the904		 * correct values.905		 */906		if (is_ax(dd)) {907			/*908			 * xmt_margin and OverwiteEnabel should be the909			 * same for Gen1/Gen2 and Gen3910			 */911			xmt_margin = 0x5;912			xmt_margin_oe = 0x1;913			lane_delay = 0xF; /* Delay 240ns. */914			lane_bundle = 0x0; /* Set to 1 lane. */915		}916 917		/* overwrite existing values */918		pcie_ctrl = (xmt_margin << MARGIN_GEN1_GEN2_SHIFT)919			| (xmt_margin_oe << MARGIN_G1_G2_OVERWRITE_SHIFT)920			| (xmt_margin << MARGIN_SHIFT)921			| (xmt_margin_oe << MARGIN_OVERWRITE_ENABLE_SHIFT)922			| (lane_delay << LANE_DELAY_SHIFT)923			| (lane_bundle << LANE_BUNDLE_SHIFT);924 925		write_csr(dd, CCE_PCIE_CTRL, pcie_ctrl);926	}927 928	dd_dev_dbg(dd, "%s: program XMT margin, CcePcieCtrl 0x%llx\n",929		   fname, pcie_ctrl);930}931 932/*933 * Do all the steps needed to transition the PCIe link to Gen3 speed.934 */935int do_pcie_gen3_transition(struct hfi1_devdata *dd)936{937	struct pci_dev *parent = dd->pcidev->bus->self;938	u64 fw_ctrl;939	u64 reg, therm;940	u32 reg32, fs, lf;941	u32 status, err;942	int ret;943	int do_retry, retry_count = 0;944	int intnum = 0;945	uint default_pset;946	uint pset = pcie_pset;947	u16 target_vector, target_speed;948	u16 lnkctl2, vendor;949	u8 div;950	const u8 (*eq)[3];951	const u8 (*ctle_tunings)[4];952	uint static_ctle_mode;953	int return_error = 0;954	u32 target_width;955 956	/* PCIe Gen3 is for the ASIC only */957	if (dd->icode != ICODE_RTL_SILICON)958		return 0;959 960	if (pcie_target == 1) {			/* target Gen1 */961		target_vector = PCI_EXP_LNKCTL2_TLS_2_5GT;962		target_speed = 2500;963	} else if (pcie_target == 2) {		/* target Gen2 */964		target_vector = PCI_EXP_LNKCTL2_TLS_5_0GT;965		target_speed = 5000;966	} else if (pcie_target == 3) {		/* target Gen3 */967		target_vector = PCI_EXP_LNKCTL2_TLS_8_0GT;968		target_speed = 8000;969	} else {970		/* off or invalid target - skip */971		dd_dev_info(dd, "%s: Skipping PCIe transition\n", __func__);972		return 0;973	}974 975	/* if already at target speed, done (unless forced) */976	if (dd->lbus_speed == target_speed) {977		dd_dev_info(dd, "%s: PCIe already at gen%d, %s\n", __func__,978			    pcie_target,979			    pcie_force ? "re-doing anyway" : "skipping");980		if (!pcie_force)981			return 0;982	}983 984	/*985	 * The driver cannot do the transition if it has no access to the986	 * upstream component987	 */988	if (!parent) {989		dd_dev_info(dd, "%s: No upstream, Can't do gen3 transition\n",990			    __func__);991		return 0;992	}993 994	/* Previous Gen1/Gen2 bus width */995	target_width = dd->lbus_width;996 997	/*998	 * Do the Gen3 transition.  Steps are those of the PCIe Gen3999	 * recipe.1000	 */1001 1002	/* step 1: pcie link working in gen1/gen2 */1003 1004	/* step 2: if either side is not capable of Gen3, done */1005	if (pcie_target == 3 && !dd->link_gen3_capable) {1006		dd_dev_err(dd, "The PCIe link is not Gen3 capable\n");1007		ret = -ENOSYS;1008		goto done_no_mutex;1009	}1010 1011	/* hold the SBus resource across the firmware download and SBR */1012	ret = acquire_chip_resource(dd, CR_SBUS, SBUS_TIMEOUT);1013	if (ret) {1014		dd_dev_err(dd, "%s: unable to acquire SBus resource\n",1015			   __func__);1016		return ret;1017	}1018 1019	/* make sure thermal polling is not causing interrupts */1020	therm = read_csr(dd, ASIC_CFG_THERM_POLL_EN);1021	if (therm) {1022		write_csr(dd, ASIC_CFG_THERM_POLL_EN, 0x0);1023		msleep(100);1024		dd_dev_info(dd, "%s: Disabled therm polling\n",1025			    __func__);1026	}1027 1028retry:1029	/* the SBus download will reset the spico for thermal */1030 1031	/* step 3: download SBus Master firmware */1032	/* step 4: download PCIe Gen3 SerDes firmware */1033	dd_dev_info(dd, "%s: downloading firmware\n", __func__);1034	ret = load_pcie_firmware(dd);1035	if (ret) {1036		/* do not proceed if the firmware cannot be downloaded */1037		return_error = 1;1038		goto done;1039	}1040 1041	/* step 5: set up device parameter settings */1042	dd_dev_info(dd, "%s: setting PCIe registers\n", __func__);1043 1044	/*1045	 * PcieCfgSpcie1 - Link Control 31046	 * Leave at reset value.  No need to set PerfEq - link equalization1047	 * will be performed automatically after the SBR when the target1048	 * speed is 8GT/s.1049	 */1050 1051	/* clear all 16 per-lane error bits (PCIe: Lane Error Status) */1052	pci_write_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, 0xffff);1053 1054	/* step 5a: Set Synopsys Port Logic registers */1055 1056	/*1057	 * PcieCfgRegPl2 - Port Force Link1058	 *1059	 * Set the low power field to 0x10 to avoid unnecessary power1060	 * management messages.  All other fields are zero.1061	 */1062	reg32 = 0x10ul << PCIE_CFG_REG_PL2_LOW_PWR_ENT_CNT_SHIFT;1063	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL2, reg32);1064 1065	/*1066	 * PcieCfgRegPl100 - Gen3 Control1067	 *1068	 * turn off PcieCfgRegPl100.Gen3ZRxDcNonCompl1069	 * turn on PcieCfgRegPl100.EqEieosCnt1070	 * Everything else zero.1071	 */1072	reg32 = PCIE_CFG_REG_PL100_EQ_EIEOS_CNT_SMASK;1073	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL100, reg32);1074 1075	/*1076	 * PcieCfgRegPl101 - Gen3 EQ FS and LF1077	 * PcieCfgRegPl102 - Gen3 EQ Presets to Coefficients Mapping1078	 * PcieCfgRegPl103 - Gen3 EQ Preset Index1079	 * PcieCfgRegPl105 - Gen3 EQ Status1080	 *1081	 * Give initial EQ settings.1082	 */1083	if (dd->pcidev->device == PCI_DEVICE_ID_INTEL0) { /* discrete */1084		/* 1000mV, FS=24, LF = 8 */1085		fs = 24;1086		lf = 8;1087		div = 3;1088		eq = discrete_preliminary_eq;1089		default_pset = DEFAULT_DISCRETE_PSET;1090		ctle_tunings = discrete_ctle_tunings;1091		/* bit 0 - discrete on/off */1092		static_ctle_mode = pcie_ctle & 0x1;1093	} else {1094		/* 400mV, FS=29, LF = 9 */1095		fs = 29;1096		lf = 9;1097		div = 1;1098		eq = integrated_preliminary_eq;1099		default_pset = DEFAULT_MCP_PSET;1100		ctle_tunings = integrated_ctle_tunings;1101		/* bit 1 - integrated on/off */1102		static_ctle_mode = (pcie_ctle >> 1) & 0x1;1103	}1104	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL101,1105			       (fs <<1106				PCIE_CFG_REG_PL101_GEN3_EQ_LOCAL_FS_SHIFT) |1107			       (lf <<1108				PCIE_CFG_REG_PL101_GEN3_EQ_LOCAL_LF_SHIFT));1109	ret = load_eq_table(dd, eq, fs, div);1110	if (ret)1111		goto done;1112 1113	/*1114	 * PcieCfgRegPl106 - Gen3 EQ Control1115	 *1116	 * Set Gen3EqPsetReqVec, leave other fields 0.1117	 */1118	if (pset == UNSET_PSET)1119		pset = default_pset;1120	if (pset > 10) {	/* valid range is 0-10, inclusive */1121		dd_dev_err(dd, "%s: Invalid Eq Pset %u, setting to %d\n",1122			   __func__, pset, default_pset);1123		pset = default_pset;1124	}1125	dd_dev_info(dd, "%s: using EQ Pset %u\n", __func__, pset);1126	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL106,1127			       ((1 << pset) <<1128			PCIE_CFG_REG_PL106_GEN3_EQ_PSET_REQ_VEC_SHIFT) |1129			PCIE_CFG_REG_PL106_GEN3_EQ_EVAL2MS_DISABLE_SMASK |1130			PCIE_CFG_REG_PL106_GEN3_EQ_PHASE23_EXIT_MODE_SMASK);1131 1132	/*1133	 * step 5b: Do post firmware download steps via SBus1134	 */1135	dd_dev_info(dd, "%s: doing pcie post steps\n", __func__);1136	pcie_post_steps(dd);1137 1138	/*1139	 * step 5c: Program gasket interrupts1140	 */1141	/* set the Rx Bit Rate to REFCLK ratio */1142	write_gasket_interrupt(dd, intnum++, 0x0006, 0x0050);1143	/* disable pCal for PCIe Gen3 RX equalization */1144	/* select adaptive or static CTLE */1145	write_gasket_interrupt(dd, intnum++, 0x0026,1146			       0x5b01 | (static_ctle_mode << 3));1147	/*1148	 * Enable iCal for PCIe Gen3 RX equalization, and set which1149	 * evaluation of RX_EQ_EVAL will launch the iCal procedure.1150	 */1151	write_gasket_interrupt(dd, intnum++, 0x0026, 0x5202);1152 1153	if (static_ctle_mode) {1154		/* apply static CTLE tunings */1155		u8 pcie_dc, pcie_lf, pcie_hf, pcie_bw;1156 1157		pcie_dc = ctle_tunings[pset][0];1158		pcie_lf = ctle_tunings[pset][1];1159		pcie_hf = ctle_tunings[pset][2];1160		pcie_bw = ctle_tunings[pset][3];1161		write_gasket_interrupt(dd, intnum++, 0x0026, 0x0200 | pcie_dc);1162		write_gasket_interrupt(dd, intnum++, 0x0026, 0x0100 | pcie_lf);1163		write_gasket_interrupt(dd, intnum++, 0x0026, 0x0000 | pcie_hf);1164		write_gasket_interrupt(dd, intnum++, 0x0026, 0x5500 | pcie_bw);1165	}1166 1167	/* terminate list */1168	write_gasket_interrupt(dd, intnum++, 0x0000, 0x0000);1169 1170	/*1171	 * step 5d: program XMT margin1172	 */1173	write_xmt_margin(dd, __func__);1174 1175	/*1176	 * step 5e: disable active state power management (ASPM). It1177	 * will be enabled if required later1178	 */1179	dd_dev_info(dd, "%s: clearing ASPM\n", __func__);1180	aspm_hw_disable_l1(dd);1181 1182	/*1183	 * step 5f: clear DirectSpeedChange1184	 * PcieCfgRegPl67.DirectSpeedChange must be zero to prevent the1185	 * change in the speed target from starting before we are ready.1186	 * This field defaults to 0 and we are not changing it, so nothing1187	 * needs to be done.1188	 */1189 1190	/* step 5g: Set target link speed */1191	/*1192	 * Set target link speed to be target on both device and parent.1193	 * On setting the parent: Some system BIOSs "helpfully" set the1194	 * parent target speed to Gen2 to match the ASIC's initial speed.1195	 * We can set the target Gen3 because we have already checked1196	 * that it is Gen3 capable earlier.1197	 */1198	dd_dev_info(dd, "%s: setting parent target link speed\n", __func__);1199	ret = pcie_capability_read_word(parent, PCI_EXP_LNKCTL2, &lnkctl2);1200	if (ret) {1201		dd_dev_err(dd, "Unable to read from PCI config\n");1202		return_error = 1;1203		goto done;1204	}1205 1206	dd_dev_info(dd, "%s: ..old link control2: 0x%x\n", __func__,1207		    (u32)lnkctl2);1208	/* only write to parent if target is not as high as ours */1209	if ((lnkctl2 & PCI_EXP_LNKCTL2_TLS) < target_vector) {1210		ret = pcie_capability_clear_and_set_word(parent, PCI_EXP_LNKCTL2,1211							 PCI_EXP_LNKCTL2_TLS,1212							 target_vector);1213		if (ret) {1214			dd_dev_err(dd, "Unable to change parent PCI target speed\n");1215			return_error = 1;1216			goto done;1217		}1218	} else {1219		dd_dev_info(dd, "%s: ..target speed is OK\n", __func__);1220	}1221 1222	dd_dev_info(dd, "%s: setting target link speed\n", __func__);1223	ret = pcie_capability_clear_and_set_word(dd->pcidev, PCI_EXP_LNKCTL2,1224						 PCI_EXP_LNKCTL2_TLS,1225						 target_vector);1226	if (ret) {1227		dd_dev_err(dd, "Unable to change device PCI target speed\n");1228		return_error = 1;1229		goto done;1230	}1231 1232	/* step 5h: arm gasket logic */1233	/* hold DC in reset across the SBR */1234	write_csr(dd, CCE_DC_CTRL, CCE_DC_CTRL_DC_RESET_SMASK);1235	(void)read_csr(dd, CCE_DC_CTRL); /* DC reset hold */1236	/* save firmware control across the SBR */1237	fw_ctrl = read_csr(dd, MISC_CFG_FW_CTRL);1238 1239	dd_dev_info(dd, "%s: arming gasket logic\n", __func__);1240	arm_gasket_logic(dd);1241 1242	/*1243	 * step 6: quiesce PCIe link1244	 * The chip has already been reset, so there will be no traffic1245	 * from the chip.  Linux has no easy way to enforce that it will1246	 * not try to access the device, so we just need to hope it doesn't1247	 * do it while we are doing the reset.1248	 */1249 1250	/*1251	 * step 7: initiate the secondary bus reset (SBR)1252	 * step 8: hardware brings the links back up1253	 * step 9: wait for link speed transition to be complete1254	 */1255	dd_dev_info(dd, "%s: calling trigger_sbr\n", __func__);1256	ret = trigger_sbr(dd);1257	if (ret)1258		goto done;1259 1260	/* step 10: decide what to do next */1261 1262	/* check if we can read PCI space */1263	ret = pci_read_config_word(dd->pcidev, PCI_VENDOR_ID, &vendor);1264	if (ret) {1265		dd_dev_info(dd,1266			    "%s: read of VendorID failed after SBR, err %d\n",1267			    __func__, ret);1268		return_error = 1;1269		goto done;1270	}1271	if (vendor == 0xffff) {1272		dd_dev_info(dd, "%s: VendorID is all 1s after SBR\n", __func__);1273		return_error = 1;1274		ret = -EIO;1275		goto done;1276	}1277 1278	/* restore PCI space registers we know were reset */1279	dd_dev_info(dd, "%s: calling restore_pci_variables\n", __func__);1280	ret = restore_pci_variables(dd);1281	if (ret) {1282		dd_dev_err(dd, "%s: Could not restore PCI variables\n",1283			   __func__);1284		return_error = 1;1285		goto done;1286	}1287 1288	/* restore firmware control */1289	write_csr(dd, MISC_CFG_FW_CTRL, fw_ctrl);1290 1291	/*1292	 * Check the gasket block status.1293	 *1294	 * This is the first CSR read after the SBR.  If the read returns1295	 * all 1s (fails), the link did not make it back.1296	 *1297	 * Once we're sure we can read and write, clear the DC reset after1298	 * the SBR.  Then check for any per-lane errors. Then look over1299	 * the status.1300	 */1301	reg = read_csr(dd, ASIC_PCIE_SD_HOST_STATUS);1302	dd_dev_info(dd, "%s: gasket block status: 0x%llx\n", __func__, reg);1303	if (reg == ~0ull) {	/* PCIe read failed/timeout */1304		dd_dev_err(dd, "SBR failed - unable to read from device\n");1305		return_error = 1;1306		ret = -ENOSYS;1307		goto done;1308	}1309 1310	/* clear the DC reset */1311	write_csr(dd, CCE_DC_CTRL, 0);1312 1313	/* Set the LED off */1314	setextled(dd, 0);1315 1316	/* check for any per-lane errors */1317	ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, &reg32);1318	if (ret) {1319		dd_dev_err(dd, "Unable to read from PCI config\n");1320		return_error = 1;1321		goto done;1322	}1323 1324	dd_dev_info(dd, "%s: per-lane errors: 0x%x\n", __func__, reg32);1325 1326	/* extract status, look for our HFI */1327	status = (reg >> ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_STS_SHIFT)1328			& ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_STS_MASK;1329	if ((status & (1 << dd->hfi1_id)) == 0) {1330		dd_dev_err(dd,1331			   "%s: gasket status 0x%x, expecting 0x%x\n",1332			   __func__, status, 1 << dd->hfi1_id);1333		ret = -EIO;1334		goto done;1335	}1336 1337	/* extract error */1338	err = (reg >> ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_ERR_SHIFT)1339		& ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_ERR_MASK;1340	if (err) {1341		dd_dev_err(dd, "%s: gasket error %d\n", __func__, err);1342		ret = -EIO;1343		goto done;1344	}1345 1346	/* update our link information cache */1347	update_lbus_info(dd);1348	dd_dev_info(dd, "%s: new speed and width: %s\n", __func__,1349		    dd->lbus_info);1350 1351	if (dd->lbus_speed != target_speed ||1352	    dd->lbus_width < target_width) { /* not target */1353		/* maybe retry */1354		do_retry = retry_count < pcie_retry;1355		dd_dev_err(dd, "PCIe link speed or width did not match target%s\n",1356			   do_retry ? ", retrying" : "");1357		retry_count++;1358		if (do_retry) {1359			msleep(100); /* allow time to settle */1360			goto retry;1361		}1362		ret = -EIO;1363	}1364 1365done:1366	if (therm) {1367		write_csr(dd, ASIC_CFG_THERM_POLL_EN, 0x1);1368		msleep(100);1369		dd_dev_info(dd, "%s: Re-enable therm polling\n",1370			    __func__);1371	}1372	release_chip_resource(dd, CR_SBUS);1373done_no_mutex:1374	/* return no error if it is OK to be at current speed */1375	if (ret && !return_error) {1376		dd_dev_err(dd, "Proceeding at current speed PCIe speed\n");1377		ret = 0;1378	}1379 1380	dd_dev_info(dd, "%s: done\n", __func__);1381	return ret;1382}1383