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tegrakernel/kernel/kernel-4.9/drivers/infiniband/hw/hfi1/pcie.c

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initial commit tegra kernel 32.6.1
2022-02-16 09:13:02 -06:00
/*
* Copyright(c) 2015, 2016 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"
/* link speed vector for Gen3 speed - not in Linux headers */
#define GEN1_SPEED_VECTOR 0x1
#define GEN2_SPEED_VECTOR 0x2
#define GEN3_SPEED_VECTOR 0x3
/*
* 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;
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->kregbase = ioremap_nocache(addr, TXE_PIO_SEND);
if (!dd->kregbase)
return -ENOMEM;
dd->piobase = ioremap_wc(addr + TXE_PIO_SEND, TXE_PIO_SIZE);
if (!dd->piobase) {
iounmap(dd->kregbase);
return -ENOMEM;
}
dd->flags |= HFI1_PRESENT; /* now register routines work */
dd->kregend = dd->kregbase + TXE_PIO_SEND;
dd->physaddr = addr; /* used for io_remap, etc. */
/*
* Re-map the chip's RcvArray as write-combining to allow us
* to write an entire cacheline worth of entries in one shot.
* If this re-map fails, just continue - the RcvArray programming
* function will handle both cases.
*/
dd->chip_rcv_array_count = read_csr(dd, RCV_ARRAY_CNT);
dd->rcvarray_wc = ioremap_wc(addr + RCV_ARRAY,
dd->chip_rcv_array_count * 8);
dd_dev_info(dd, "WC Remapped RcvArray: %p\n", dd->rcvarray_wc);
/*
* Save BARs and command to rewrite after device reset.
*/
dd->pcibar0 = addr;
dd->pcibar1 = addr >> 32;
pci_read_config_dword(dd->pcidev, PCI_ROM_ADDRESS, &dd->pci_rom);
pci_read_config_word(dd->pcidev, PCI_COMMAND, &dd->pci_command);
pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL, &dd->pcie_devctl);
pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL, &dd->pcie_lnkctl);
pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL2,
&dd->pcie_devctl2);
pci_read_config_dword(dd->pcidev, PCI_CFG_MSIX0, &dd->pci_msix0);
pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE1, &dd->pci_lnkctl3);
pci_read_config_dword(dd->pcidev, PCIE_CFG_TPH2, &dd->pci_tph2);
return 0;
}
/*
* 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)
{
u64 __iomem *base = (void __iomem *)dd->kregbase;
dd->flags &= ~HFI1_PRESENT;
dd->kregbase = NULL;
iounmap(base);
if (dd->rcvarray_wc)
iounmap(dd->rcvarray_wc);
if (dd->piobase)
iounmap(dd->piobase);
}
/*
* Do a Function Level Reset (FLR) on the device.
* Based on static function drivers/pci/pci.c:pcie_flr().
*/
void hfi1_pcie_flr(struct hfi1_devdata *dd)
{
int i;
u16 status;
/* no need to check for the capability - we know the device has it */
/* wait for Transaction Pending bit to clear, at most a few ms */
for (i = 0; i < 4; i++) {
if (i)
msleep((1 << (i - 1)) * 100);
pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVSTA, &status);
if (!(status & PCI_EXP_DEVSTA_TRPND))
goto clear;
}
dd_dev_err(dd, "Transaction Pending bit is not clearing, proceeding with reset anyway\n");
clear:
pcie_capability_set_word(dd->pcidev, PCI_EXP_DEVCTL,
PCI_EXP_DEVCTL_BCR_FLR);
/* PCIe spec requires the function to be back within 100ms */
msleep(100);
}
static void msix_setup(struct hfi1_devdata *dd, int pos, u32 *msixcnt,
struct hfi1_msix_entry *hfi1_msix_entry)
{
int ret;
int nvec = *msixcnt;
struct msix_entry *msix_entry;
int i;
/*
* We can't pass hfi1_msix_entry array to msix_setup
* so use a dummy msix_entry array and copy the allocated
* irq back to the hfi1_msix_entry array.
*/
msix_entry = kmalloc_array(nvec, sizeof(*msix_entry), GFP_KERNEL);
if (!msix_entry) {
ret = -ENOMEM;
goto do_intx;
}
for (i = 0; i < nvec; i++)
msix_entry[i] = hfi1_msix_entry[i].msix;
ret = pci_enable_msix_range(dd->pcidev, msix_entry, 1, nvec);
if (ret < 0)
goto free_msix_entry;
nvec = ret;
for (i = 0; i < nvec; i++)
hfi1_msix_entry[i].msix = msix_entry[i];
kfree(msix_entry);
*msixcnt = nvec;
return;
free_msix_entry:
kfree(msix_entry);
do_intx:
dd_dev_err(dd, "pci_enable_msix_range %d vectors failed: %d, falling back to INTx\n",
nvec, ret);
*msixcnt = 0;
hfi1_enable_intx(dd->pcidev);
}
/* 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 GEN3_SPEED_VECTOR:
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;
pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKSTA, &linkstat);
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;
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;
pcie_capability_read_dword(dd->pcidev, PCI_EXP_LNKCAP, &linkcap);
if ((linkcap & PCI_EXP_LNKCAP_SLS) != GEN3_SPEED_VECTOR) {
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 in *nent:
* - actual number of interrupts allocated
* - 0 if fell back to INTx.
*/
void request_msix(struct hfi1_devdata *dd, u32 *nent,
struct hfi1_msix_entry *entry)
{
int pos;
pos = dd->pcidev->msix_cap;
if (*nent && pos) {
msix_setup(dd, pos, nent, entry);
/* did it, either MSI-X or INTx */
} else {
*nent = 0;
hfi1_enable_intx(dd->pcidev);
}
tune_pcie_caps(dd);
}
void hfi1_enable_intx(struct pci_dev *pdev)
{
/* first, turn on INTx */
pci_intx(pdev, 1);
/* then turn off MSI-X */
pci_disable_msix(pdev);
}
/* restore command and BARs after a reset has wiped them out */
void restore_pci_variables(struct hfi1_devdata *dd)
{
pci_write_config_word(dd->pcidev, PCI_COMMAND, dd->pci_command);
pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0, dd->pcibar0);
pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1, dd->pcibar1);
pci_write_config_dword(dd->pcidev, PCI_ROM_ADDRESS, dd->pci_rom);
pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL, dd->pcie_devctl);
pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL, dd->pcie_lnkctl);
pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL2,
dd->pcie_devctl2);
pci_write_config_dword(dd->pcidev, PCI_CFG_MSIX0, dd->pci_msix0);
pci_write_config_dword(dd->pcidev, PCIE_CFG_SPCIE1, dd->pci_lnkctl3);
pci_write_config_dword(dd->pcidev, PCIE_CFG_TPH2, dd->pci_tph2);
}
/*
* 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;
/*
* Turn on extended tags in DevCtl in case the BIOS has turned it off
* to improve WFR SDMA bandwidth
*/
pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL, &ectl);
if (!(ectl & PCI_EXP_DEVCTL_EXT_TAG)) {
dd_dev_info(dd, "Enabling PCIe extended tags\n");
ectl |= PCI_EXP_DEVCTL_EXT_TAG;
pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL, ectl);
}
/* 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)
return;
if (!pci_is_root_bus(parent->bus)) {
dd_dev_info(dd, "Parent not root\n");
return;
}
if (!pci_is_pcie(parent) || !pci_is_pcie(dd->pcidev))
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 %Lx, 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 pci_ers_result_t
pci_link_reset(struct pci_dev *pdev)
{
struct hfi1_devdata *dd = pci_get_drvdata(pdev);
dd_dev_info(dd, "HFI1 link_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,
.link_reset = pci_link_reset,
.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 */
/* mask for PCIe capability register lnkctl2 target link speed */
#define LNKCTL2_TARGET_LINK_SPEED_MASK 0xf
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;
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 */
pci_read_config_dword(dd->pcidev, PCIE_CFG_REG_PL105,
&violation);
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;
}
/*
* A secondary bus reset (SBR) issues a hot reset to our device.
* The following routine does a 1s wait after the reset is dropped
* per PCI Trhfa (recovery time). PCIe 3.0 section 6.6.1 -
* Conventional Reset, paragraph 3, line 35 also says that a 1s
* delay after a reset is required. Per spec requirements,
* the link is either working or not after that point.
*/
pci_reset_bridge_secondary_bus(dev->bus->self);
return 0;
}
/*
* 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;
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 = GEN1_SPEED_VECTOR;
target_speed = 2500;
} else if (pcie_target == 2) { /* target Gen2 */
target_vector = GEN2_SPEED_VECTOR;
target_speed = 5000;
} else if (pcie_target == 3) { /* target Gen3 */
target_vector = GEN3_SPEED_VECTOR;
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 (pcie_pset == UNSET_PSET)
pcie_pset = default_pset;
if (pcie_pset > 10) { /* valid range is 0-10, inclusive */
dd_dev_err(dd, "%s: Invalid Eq Pset %u, setting to %d\n",
__func__, pcie_pset, default_pset);
pcie_pset = default_pset;
}
dd_dev_info(dd, "%s: using EQ Pset %u\n", __func__, pcie_pset);
pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL106,
((1 << pcie_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[pcie_pset][0];
pcie_lf = ctle_tunings[pcie_pset][1];
pcie_hf = ctle_tunings[pcie_pset][2];
pcie_bw = ctle_tunings[pcie_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__);
pcie_capability_read_word(parent, PCI_EXP_LNKCTL2, &lnkctl2);
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 & LNKCTL2_TARGET_LINK_SPEED_MASK) < target_vector) {
lnkctl2 &= ~LNKCTL2_TARGET_LINK_SPEED_MASK;
lnkctl2 |= target_vector;
dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__,
(u32)lnkctl2);
pcie_capability_write_word(parent, PCI_EXP_LNKCTL2, lnkctl2);
} else {
dd_dev_info(dd, "%s: ..target speed is OK\n", __func__);
}
dd_dev_info(dd, "%s: setting target link speed\n", __func__);
pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL2, &lnkctl2);
dd_dev_info(dd, "%s: ..old link control2: 0x%x\n", __func__,
(u32)lnkctl2);
lnkctl2 &= ~LNKCTL2_TARGET_LINK_SPEED_MASK;
lnkctl2 |= target_vector;
dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__,
(u32)lnkctl2);
pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL2, lnkctl2);
/* 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__);
restore_pci_variables(dd);
/* 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 */
pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, &reg32);
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;
}