[PATCH for-next 2/3] IB/hfi1: Check return values from PCI config API calls

Dennis Dalessandro
2017-06-30T20:14:40Z

From: Bartlomiej Dudek <bartlomiej.dudek-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>

Ensure that return values from kernel PCI config access
API calls in HFI driver are checked and react properly if
they are not expected (i.e. not successful).

Reviewed-by: Jakub Byczkowski <jakub.byczkowski-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Bartlomiej Dudek <bartlomiej.dudek-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
drivers/infiniband/hw/hfi1/chip.c | 22 +++
drivers/infiniband/hw/hfi1/hfi.h | 2
drivers/infiniband/hw/hfi1/pcie.c | 238 ++++++++++++++++++++++++++++++-------
3 files changed, 215 insertions(+), 47 deletions(-)

diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c
index 937350d..efc8481 100644
--- a/drivers/infiniband/hw/hfi1/chip.c
+++ b/drivers/infiniband/hw/hfi1/chip.c
@@ -13846,9 +13846,10 @@ static void init_sc2vl_tables(struct hfi1_devdata *dd)
* a reset following the (possible) FLR in this routine.
*
*/
-static void init_chip(struct hfi1_devdata *dd)
+static int init_chip(struct hfi1_devdata *dd)
{
int i;
+ int ret = 0;

/*
* Put the HFI CSRs in a known state.
@@ -13896,12 +13897,22 @@ static void init_chip(struct hfi1_devdata *dd)
pcie_flr(dd->pcidev);

/* restore command and BARs */
- restore_pci_variables(dd);
+ ret = restore_pci_variables(dd);
+ if (ret) {
+ dd_dev_err(dd, "%s: Could not restore PCI variables\n",
+ __func__);
+ return ret;
+ }

if (is_ax(dd)) {
dd_dev_info(dd, "Resetting CSRs with FLR\n");
pcie_flr(dd->pcidev);
- restore_pci_variables(dd);
+ ret = restore_pci_variables(dd);
+ if (ret) {
+ dd_dev_err(dd, "%s: Could not restore PCI variables\n",
+ __func__);
+ return ret;
+ }
}
} else {
dd_dev_info(dd, "Resetting CSRs with writes\n");
@@ -13929,6 +13940,7 @@ static void init_chip(struct hfi1_devdata *dd)
write_csr(dd, ASIC_QSFP1_OUT, 0x1f);
write_csr(dd, ASIC_QSFP2_OUT, 0x1f);
init_chip_resources(dd);
+ return ret;
}

static void init_early_variables(struct hfi1_devdata *dd)
@@ -14914,7 +14926,9 @@ struct hfi1_devdata *hfi1_init_dd(struct pci_dev *pdev,
goto bail_cleanup;

/* obtain chip sizes, reset chip CSRs */
- init_chip(dd);
+ ret = init_chip(dd);
+ if (ret)
+ goto bail_cleanup;

/* read in the PCIe link speed information */
ret = pcie_speeds(dd);
diff --git a/drivers/infiniband/hw/hfi1/hfi.h b/drivers/infiniband/hw/hfi1/hfi.h
index 1a33a50..62f843d 100644
--- a/drivers/infiniband/hw/hfi1/hfi.h
+++ b/drivers/infiniband/hw/hfi1/hfi.h
@@ -1854,7 +1854,7 @@ int hfi1_create_port_files(struct ib_device *ibdev, u8 port_num,
void hfi1_pcie_ddcleanup(struct hfi1_devdata *);
int pcie_speeds(struct hfi1_devdata *dd);
int request_msix(struct hfi1_devdata *dd, u32 msireq);
-void restore_pci_variables(struct hfi1_devdata *dd);
+int restore_pci_variables(struct hfi1_devdata *dd);
int do_pcie_gen3_transition(struct hfi1_devdata *dd);
int parse_platform_config(struct hfi1_devdata *dd);
int get_platform_config_field(struct hfi1_devdata *dd,
diff --git a/drivers/infiniband/hw/hfi1/pcie.c b/drivers/infiniband/hw/hfi1/pcie.c
index f01841b..676efdf 100644
--- a/drivers/infiniband/hw/hfi1/pcie.c
+++ b/drivers/infiniband/hw/hfi1/pcie.c
@@ -68,7 +68,7 @@
/*
* Code to adjust PCIe capabilities.
*/
-static void tune_pcie_caps(struct hfi1_devdata *);
+static int tune_pcie_caps(struct hfi1_devdata *);

/*
* Do all the common PCIe setup and initialization.
@@ -161,6 +161,7 @@ int hfi1_pcie_ddinit(struct hfi1_devdata *dd, struct pci_dev *pdev)
{
unsigned long len;
resource_size_t addr;
+ int ret = 0;

dd->pcidev = pdev;
pci_set_drvdata(pdev, dd);
@@ -207,19 +208,56 @@ int hfi1_pcie_ddinit(struct hfi1_devdata *dd, struct pci_dev *pdev)
/*
* Save BARs and command to rewrite after device reset.
*/
- pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0, &dd->pcibar0);
- pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1, &dd->pcibar1);
- 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);
+
+ ret = pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0, &dd->pcibar0);
+ if (ret)
+ goto read_error;
+
+ ret = pci_read_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1, &dd->pcibar1);
+ if (ret)
+ goto read_error;
+
+ ret = pci_read_config_dword(dd->pcidev, PCI_ROM_ADDRESS, &dd->pci_rom);
+ if (ret)
+ goto read_error;
+
+ ret = pci_read_config_word(dd->pcidev, PCI_COMMAND, &dd->pci_command);
+ if (ret)
+ goto read_error;
+
+ ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL,
+ &dd->pcie_devctl);
+ if (ret)
+ goto read_error;
+
+ ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL,
+ &dd->pcie_lnkctl);
+ if (ret)
+ goto read_error;
+
+ ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL2,
+ &dd->pcie_devctl2);
+ if (ret)
+ goto read_error;
+
+ ret = pci_read_config_dword(dd->pcidev, PCI_CFG_MSIX0, &dd->pci_msix0);
+ if (ret)
+ goto read_error;
+
+ ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE1,
+ &dd->pci_lnkctl3);
+ if (ret)
+ goto read_error;
+
+ ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_TPH2, &dd->pci_tph2);
+ if (ret)
+ goto read_error;

return 0;
+
+read_error:
+ dd_dev_err(dd, "Unable to read from PCI config\n");
+ return ret;
}

/*
@@ -270,8 +308,14 @@ static u32 extract_width(u16 linkstat)
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;
+ }

- 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),
@@ -286,6 +330,7 @@ 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");
@@ -295,7 +340,12 @@ int pcie_speeds(struct hfi1_devdata *dd)
/* 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);
+ 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) != GEN3_SPEED_VECTOR) {
dd_dev_info(dd,
"This HFI is not Gen3 capable, max speed 0x%x, need 0x3\n",
@@ -327,7 +377,7 @@ int pcie_speeds(struct hfi1_devdata *dd)
*/
int request_msix(struct hfi1_devdata *dd, u32 msireq)
{
- int nvec;
+ int nvec, ret;

nvec = pci_alloc_irq_vectors(dd->pcidev, 1, msireq,
PCI_IRQ_MSIX | PCI_IRQ_LEGACY);
@@ -336,7 +386,12 @@ int request_msix(struct hfi1_devdata *dd, u32 msireq)
return nvec;
}

- tune_pcie_caps(dd);
+ ret = tune_pcie_caps(dd);
+ if (ret) {
+ dd_dev_err(dd, "tune_pcie_caps() failed: %d\n", ret);
+ pci_free_irq_vectors(dd->pcidev);
+ return ret;
+ }

/* check for legacy IRQ */
if (nvec == 1 && !dd->pcidev->msix_enabled)
@@ -346,19 +401,61 @@ int request_msix(struct hfi1_devdata *dd, u32 msireq)
}

/* restore command and BARs after a reset has wiped them out */
-void restore_pci_variables(struct hfi1_devdata *dd)
+int 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);
+ 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;
+
+ ret = pci_write_config_dword(dd->pcidev, PCIE_CFG_SPCIE1,
+ dd->pci_lnkctl3);
+ if (ret)
+ goto error;
+
+ 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;
}

/*
@@ -373,21 +470,33 @@ void restore_pci_variables(struct hfi1_devdata *dd)
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)
+static int 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
*/
- pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL, &ectl);
+ ret = pcie_capability_read_word(dd->pcidev,
+ PCI_EXP_DEVCTL, &ectl);
+ if (ret) {
+ dd_dev_err(dd, "Unable to read from PCI config\n");
+ return ret;
+ }
+
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);
+ ret = pcie_capability_write_word(dd->pcidev,
+ PCI_EXP_DEVCTL, ectl);
+ if (ret) {
+ dd_dev_err(dd, "Unable to write to PCI config\n");
+ return ret;
+ }
}
/* Find out supported and configured values for parent (root) */
parent = dd->pcidev->bus->self;
@@ -396,14 +505,14 @@ static void tune_pcie_caps(struct hfi1_devdata *dd)
* access to the upstream component.
*/
if (!parent)
- return;
+ return -EINVAL;
if (!pci_is_root_bus(parent->bus)) {
dd_dev_info(dd, "Parent not root\n");
- return;
+ return -EINVAL;
}

if (!pci_is_pcie(parent) || !pci_is_pcie(dd->pcidev))
- return;
+ return -EINVAL;
rc_mpss = parent->pcie_mpss;
rc_mps = ffs(pcie_get_mps(parent)) - 8;
/* Find out supported and configured values for endpoint (us) */
@@ -449,6 +558,8 @@ static void tune_pcie_caps(struct hfi1_devdata *dd)
ep_mrrs = max_mrrs;
pcie_set_readrq(dd->pcidev, ep_mrrs);
}
+
+ return 0;
}

/* End of PCIe capability tuning */
@@ -680,6 +791,7 @@ static int load_eq_table(struct hfi1_devdata *dd, const u8 eq[11][3], u8 fs,
u32 violation;
u32 i;
u8 c_minus1, c0, c_plus1;
+ int ret;

for (i = 0; i < 11; i++) {
/* set index */
@@ -691,8 +803,14 @@ static int load_eq_table(struct hfi1_devdata *dd, const u8 eq[11][3], u8 fs,
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);
+ 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) {
@@ -1146,7 +1264,13 @@ int do_pcie_gen3_transition(struct hfi1_devdata *dd)
* 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);
+ 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 */
@@ -1155,20 +1279,37 @@ int do_pcie_gen3_transition(struct hfi1_devdata *dd)
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);
+ 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__);
- pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL2, &lnkctl2);
+ 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 &= ~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);
+ 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 */
@@ -1218,7 +1359,14 @@ int do_pcie_gen3_transition(struct hfi1_devdata *dd)

/* restore PCI space registers we know were reset */
dd_dev_info(dd, "%s: calling restore_pci_variables\n", __func__);
- restore_pci_variables(dd);
+ 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);

@@ -1248,7 +1396,13 @@ int do_pcie_gen3_transition(struct hfi1_devdata *dd)
setextled(dd, 0);

/* check for any per-lane errors */
- pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, &reg32);
+ ret = pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, &reg32);
+ 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 */