pds_core: Clear BARs on reset

[ Upstream commit e96094c1d11cce4deb5da3c0500d49041ab845b8 ]

During reset the BARs might be accessed when they are
unmapped. This can cause unexpected issues, so fix it by
clearing the cached BAR values so they are not accessed
until they are re-mapped.

Also, make sure any places that can access the BARs
when they are NULL are prevented.

Fixes: 49ce92fbee0b ("pds_core: add FW update feature to devlink")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://lore.kernel.org/r/20240129234035.69802-6-brett.creeley@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/amd/pds_core/adminq.c b/drivers/net/ethernet/amd/pds_core/adminq.c
index 5edff33d56f3603f0133ec96458222823ac2d8ae..ea773cfa0af67bd06d86037bc8208b4111b3bbc5 100644 (file)
--- a/drivers/net/ethernet/amd/pds_core/adminq.c
+++ b/drivers/net/ethernet/amd/pds_core/adminq.c
@@ -191,10 +191,16 @@ static int __pdsc_adminq_post(struct pdsc *pdsc,
 
        /* Check that the FW is running */
        if (!pdsc_is_fw_running(pdsc)) {
-               u8 fw_status = ioread8(&pdsc->info_regs->fw_status);
-
-               dev_info(pdsc->dev, "%s: post failed - fw not running %#02x:\n",
-                        __func__, fw_status);
+               if (pdsc->info_regs) {
+                       u8 fw_status =
+                               ioread8(&pdsc->info_regs->fw_status);
+
+                       dev_info(pdsc->dev, "%s: post failed - fw not running %#02x:\n",
+                                __func__, fw_status);
+               } else {
+                       dev_info(pdsc->dev, "%s: post failed - BARs not setup\n",
+                                __func__);
+               }
                ret = -ENXIO;
 
                goto err_out_unlock;
@@ -266,10 +272,16 @@ int pdsc_adminq_post(struct pdsc *pdsc,
                        break;
 
                if (!pdsc_is_fw_running(pdsc)) {
-                       u8 fw_status = ioread8(&pdsc->info_regs->fw_status);
-
-                       dev_dbg(pdsc->dev, "%s: post wait failed - fw not running %#02x:\n",
-                               __func__, fw_status);
+                       if (pdsc->info_regs) {
+                               u8 fw_status =
+                                       ioread8(&pdsc->info_regs->fw_status);
+
+                               dev_dbg(pdsc->dev, "%s: post wait failed - fw not running %#02x:\n",
+                                       __func__, fw_status);
+                       } else {
+                               dev_dbg(pdsc->dev, "%s: post wait failed - BARs not setup\n",
+                                       __func__);
+                       }
                        err = -ENXIO;
                        break;
                }

diff --git a/drivers/net/ethernet/amd/pds_core/dev.c b/drivers/net/ethernet/amd/pds_core/dev.c
index eb178728edba9ce80308779eda567dc66a9c7390..1d590eb463d0b5505b0c1ae57d118e8c2cfc0cce 100644 (file)
--- a/drivers/net/ethernet/amd/pds_core/dev.c
+++ b/drivers/net/ethernet/amd/pds_core/dev.c
@@ -55,6 +55,9 @@ int pdsc_err_to_errno(enum pds_core_status_code code)
 
 bool pdsc_is_fw_running(struct pdsc *pdsc)
 {
+       if (!pdsc->info_regs)
+               return false;
+
        pdsc->fw_status = ioread8(&pdsc->info_regs->fw_status);
        pdsc->last_fw_time = jiffies;
        pdsc->last_hb = ioread32(&pdsc->info_regs->fw_heartbeat);
@@ -175,13 +178,17 @@ int pdsc_devcmd_locked(struct pdsc *pdsc, union pds_core_dev_cmd *cmd,
 {
        int err;
 
+       if (!pdsc->cmd_regs)
+               return -ENXIO;
+
        memcpy_toio(&pdsc->cmd_regs->cmd, cmd, sizeof(*cmd));
        pdsc_devcmd_dbell(pdsc);
        err = pdsc_devcmd_wait(pdsc, cmd->opcode, max_seconds);
-       memcpy_fromio(comp, &pdsc->cmd_regs->comp, sizeof(*comp));
 
        if ((err == -ENXIO || err == -ETIMEDOUT) && pdsc->wq)
                queue_work(pdsc->wq, &pdsc->health_work);
+       else
+               memcpy_fromio(comp, &pdsc->cmd_regs->comp, sizeof(*comp));
 
        return err;
 }

diff --git a/drivers/net/ethernet/amd/pds_core/devlink.c b/drivers/net/ethernet/amd/pds_core/devlink.c
index d2abf32b93fe3f83c566ad4eb005a0c6461cddaf..d8218bb153d9eda39c35427623606ccd26e1b912 100644 (file)
--- a/drivers/net/ethernet/amd/pds_core/devlink.c
+++ b/drivers/net/ethernet/amd/pds_core/devlink.c
@@ -111,7 +111,8 @@ int pdsc_dl_info_get(struct devlink *dl, struct devlink_info_req *req,
 
        mutex_lock(&pdsc->devcmd_lock);
        err = pdsc_devcmd_locked(pdsc, &cmd, &comp, pdsc->devcmd_timeout * 2);
-       memcpy_fromio(&fw_list, pdsc->cmd_regs->data, sizeof(fw_list));
+       if (!err)
+               memcpy_fromio(&fw_list, pdsc->cmd_regs->data, sizeof(fw_list));
        mutex_unlock(&pdsc->devcmd_lock);
        if (err && err != -EIO)
                return err;

diff --git a/drivers/net/ethernet/amd/pds_core/fw.c b/drivers/net/ethernet/amd/pds_core/fw.c
index 90a811f3878ae974679bc5caba97e18aae04bdfb..fa626719e68d1b206fc9bbe1d038daf51984f19b 100644 (file)
--- a/drivers/net/ethernet/amd/pds_core/fw.c
+++ b/drivers/net/ethernet/amd/pds_core/fw.c
@@ -107,6 +107,9 @@ int pdsc_firmware_update(struct pdsc *pdsc, const struct firmware *fw,
 
        dev_info(pdsc->dev, "Installing firmware\n");
 
+       if (!pdsc->cmd_regs)
+               return -ENXIO;
+
        dl = priv_to_devlink(pdsc);
        devlink_flash_update_status_notify(dl, "Preparing to flash",
                                           NULL, 0, 0);

diff --git a/drivers/net/ethernet/amd/pds_core/main.c b/drivers/net/ethernet/amd/pds_core/main.c
index 4c7f982c12a1d2d87dd52adc5bda4480ca1dde93..7471a751e4d810b4cd4f3330e1548b8e13165be7 100644 (file)
--- a/drivers/net/ethernet/amd/pds_core/main.c
+++ b/drivers/net/ethernet/amd/pds_core/main.c
@@ -37,6 +37,11 @@ static void pdsc_unmap_bars(struct pdsc *pdsc)
        struct pdsc_dev_bar *bars = pdsc->bars;
        unsigned int i;
 
+       pdsc->info_regs = NULL;
+       pdsc->cmd_regs = NULL;
+       pdsc->intr_status = NULL;
+       pdsc->intr_ctrl = NULL;
+
        for (i = 0; i < PDS_CORE_BARS_MAX; i++) {
                if (bars[i].vaddr)
                        pci_iounmap(pdsc->pdev, bars[i].vaddr);