ata: ahci: Disable SXS for Hisilicon Kunpeng920

mainline inclusion
from mainline-v5.12-rc6
commit 234e6d2c
category: bugfix
bugzilla: NA
CVE: NA

On Hisilicon Kunpeng920, ESP is set to 1 by default for all ports of
SATA controller. In some scenarios, some ports are not external SATA ports,
and it cause disks connected to these ports to be identified as removable
disks. So disable the SXS capability on the software side to prevent users
from mistakenly considering non-removable disks as removable disks and
performing related operations.
Signed-off-by: NXingui Yang <yangxingui@huawei.com>
Signed-off-by: NLuo Jiaxing <luojiaxing@huawei.com>
Reviewed-by: NJohn Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1615544676-61926-1-git-send-email-luojiaxing@huawei.comSigned-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NYang Xingui <yangxingui@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/ata/ahci.c

@@ -1760,6 +1760,11 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		hpriv->flags |= AHCI_HFLAG_NO_DEVSLP;
 
 #ifdef CONFIG_ARM64
+	if (pdev->vendor == PCI_VENDOR_ID_HUAWEI &&
+	    pdev->device == 0xa235 &&
+	    pdev->revision < 0x30)
+		hpriv->flags |= AHCI_HFLAG_NO_SXS;
+
 	if (pdev->vendor == 0x177d && pdev->device == 0xa01c)
 		hpriv->irq_handler = ahci_thunderx_irq_handler;
 #endif

drivers/ata/ahci.h

@@ -254,6 +254,7 @@ enum {
 	AHCI_HFLAG_IS_MOBILE		= (1 << 25), /* mobile chipset, use
 							SATA_MOBILE_LPM_POLICY
 							as default lpm_policy */
+	AHCI_HFLAG_NO_SXS		= (1 << 28), /* SXS not supported */
 
 	/* ap->flags bits */
 

drivers/ata/libahci.c

@@ -510,6 +510,11 @@ void ahci_save_initial_config(struct device *dev, struct ahci_host_priv *hpriv)
 		cap |= HOST_CAP_ALPM;
 	}
 
+	if ((cap & HOST_CAP_SXS) && (hpriv->flags & AHCI_HFLAG_NO_SXS)) {
+		dev_info(dev, "controller does not support SXS, disabling CAP_SXS\n");
+		cap &= ~HOST_CAP_SXS;
+	}
+
 	if (hpriv->force_port_map && port_map != hpriv->force_port_map) {
 		dev_info(dev, "forcing port_map 0x%x -> 0x%x\n",
 			 port_map, hpriv->force_port_map);