Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
index fc0fe4d..0538348 100644
--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -61,7 +61,8 @@
 #define   PIO_COMPLETION_STATUS_UR		1
 #define   PIO_COMPLETION_STATUS_CRS		2
 #define   PIO_COMPLETION_STATUS_CA		4
-#define   PIO_NON_POSTED_REQ			BIT(0)
+#define   PIO_NON_POSTED_REQ			BIT(10)
+#define   PIO_ERR_STATUS			BIT(11)
 #define PIO_ADDR_LS				(PIO_BASE_ADDR + 0x8)
 #define PIO_ADDR_MS				(PIO_BASE_ADDR + 0xc)
 #define PIO_WR_DATA				(PIO_BASE_ADDR + 0x10)
@@ -127,6 +128,7 @@
 #define     LTSSM_MASK				0x3f
 #define     LTSSM_L0				0x10
 #define     RC_BAR_CONFIG			0x300
+#define VENDOR_ID_REG				(LMI_BASE_ADDR + 0x44)
 
 /* PCIe core controller registers */
 #define CTRL_CORE_BASE_ADDR			0x18000
@@ -175,11 +177,14 @@
 	(PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn))	| \
 	 PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where))
 
-#define PIO_TIMEOUT_MS			1
+#define PIO_RETRY_CNT			750000 /* 1.5 s */
+#define PIO_RETRY_DELAY			2 /* 2 us*/
 
 #define LINK_WAIT_MAX_RETRIES		10
 #define LINK_WAIT_USLEEP_MIN		90000
 #define LINK_WAIT_USLEEP_MAX		100000
+#define RETRAIN_WAIT_MAX_RETRIES	10
+#define RETRAIN_WAIT_USLEEP_US		2000
 
 #define MSI_IRQ_NUM			32
 
@@ -189,6 +194,7 @@
 	struct list_head resources;
 	struct irq_domain *irq_domain;
 	struct irq_chip irq_chip;
+	raw_spinlock_t irq_lock;
 	struct irq_domain *msi_domain;
 	struct irq_domain *msi_inner_domain;
 	struct irq_chip msi_bottom_irq_chip;
@@ -239,6 +245,17 @@
 	return -ETIMEDOUT;
 }
 
+static void advk_pcie_wait_for_retrain(struct advk_pcie *pcie)
+{
+	size_t retries;
+
+	for (retries = 0; retries < RETRAIN_WAIT_MAX_RETRIES; ++retries) {
+		if (!advk_pcie_link_up(pcie))
+			break;
+		udelay(RETRAIN_WAIT_USLEEP_US);
+	}
+}
+
 static void advk_pcie_setup_hw(struct advk_pcie *pcie)
 {
 	u32 reg;
@@ -254,6 +271,16 @@
 	reg |= (IS_RC_MSK << IS_RC_SHIFT);
 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
 
+	/*
+	 * Replace incorrect PCI vendor id value 0x1b4b by correct value 0x11ab.
+	 * VENDOR_ID_REG contains vendor id in low 16 bits and subsystem vendor
+	 * id in high 16 bits. Updating this register changes readback value of
+	 * read-only vendor id bits in PCIE_CORE_DEV_ID_REG register. Workaround
+	 * for erratum 4.1: "The value of device and vendor ID is incorrect".
+	 */
+	reg = (PCI_VENDOR_ID_MARVELL << 16) | PCI_VENDOR_ID_MARVELL;
+	advk_writel(pcie, reg, VENDOR_ID_REG);
+
 	/* Set Advanced Error Capabilities and Control PF0 register */
 	reg = PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX |
 		PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX_EN |
@@ -331,10 +358,6 @@
 
 	advk_pcie_wait_for_link(pcie);
 
-	reg = PCIE_CORE_LINK_L0S_ENTRY |
-		(1 << PCIE_CORE_LINK_WIDTH_SHIFT);
-	advk_writel(pcie, reg, PCIE_CORE_LINK_CTRL_STAT_REG);
-
 	reg = advk_readl(pcie, PCIE_CORE_CMD_STATUS_REG);
 	reg |= PCIE_CORE_CMD_MEM_ACCESS_EN |
 		PCIE_CORE_CMD_IO_ACCESS_EN |
@@ -342,7 +365,7 @@
 	advk_writel(pcie, reg, PCIE_CORE_CMD_STATUS_REG);
 }
 
-static void advk_pcie_check_pio_status(struct advk_pcie *pcie)
+static int advk_pcie_check_pio_status(struct advk_pcie *pcie, u32 *val)
 {
 	struct device *dev = &pcie->pdev->dev;
 	u32 reg;
@@ -353,14 +376,49 @@
 	status = (reg & PIO_COMPLETION_STATUS_MASK) >>
 		PIO_COMPLETION_STATUS_SHIFT;
 
-	if (!status)
-		return;
-
+	/*
+	 * According to HW spec, the PIO status check sequence as below:
+	 * 1) even if COMPLETION_STATUS(bit9:7) indicates successful,
+	 *    it still needs to check Error Status(bit11), only when this bit
+	 *    indicates no error happen, the operation is successful.
+	 * 2) value Unsupported Request(1) of COMPLETION_STATUS(bit9:7) only
+	 *    means a PIO write error, and for PIO read it is successful with
+	 *    a read value of 0xFFFFFFFF.
+	 * 3) value Completion Retry Status(CRS) of COMPLETION_STATUS(bit9:7)
+	 *    only means a PIO write error, and for PIO read it is successful
+	 *    with a read value of 0xFFFF0001.
+	 * 4) value Completer Abort (CA) of COMPLETION_STATUS(bit9:7) means
+	 *    error for both PIO read and PIO write operation.
+	 * 5) other errors are indicated as 'unknown'.
+	 */
 	switch (status) {
+	case PIO_COMPLETION_STATUS_OK:
+		if (reg & PIO_ERR_STATUS) {
+			strcomp_status = "COMP_ERR";
+			break;
+		}
+		/* Get the read result */
+		if (val)
+			*val = advk_readl(pcie, PIO_RD_DATA);
+		/* No error */
+		strcomp_status = NULL;
+		break;
 	case PIO_COMPLETION_STATUS_UR:
 		strcomp_status = "UR";
 		break;
 	case PIO_COMPLETION_STATUS_CRS:
+		/* PCIe r4.0, sec 2.3.2, says:
+		 * If CRS Software Visibility is not enabled, the Root Complex
+		 * must re-issue the Configuration Request as a new Request.
+		 * A Root Complex implementation may choose to limit the number
+		 * of Configuration Request/CRS Completion Status loops before
+		 * determining that something is wrong with the target of the
+		 * Request and taking appropriate action, e.g., complete the
+		 * Request to the host as a failed transaction.
+		 *
+		 * To simplify implementation do not re-issue the Configuration
+		 * Request and complete the Request as a failed transaction.
+		 */
 		strcomp_status = "CRS";
 		break;
 	case PIO_COMPLETION_STATUS_CA:
@@ -371,6 +429,9 @@
 		break;
 	}
 
+	if (!strcomp_status)
+		return 0;
+
 	if (reg & PIO_NON_POSTED_REQ)
 		str_posted = "Non-posted";
 	else
@@ -378,25 +439,26 @@
 
 	dev_err(dev, "%s PIO Response Status: %s, %#x @ %#x\n",
 		str_posted, strcomp_status, reg, advk_readl(pcie, PIO_ADDR_LS));
+
+	return -EFAULT;
 }
 
 static int advk_pcie_wait_pio(struct advk_pcie *pcie)
 {
 	struct device *dev = &pcie->pdev->dev;
-	unsigned long timeout;
+	int i;
 
-	timeout = jiffies + msecs_to_jiffies(PIO_TIMEOUT_MS);
-
-	while (time_before(jiffies, timeout)) {
+	for (i = 0; i < PIO_RETRY_CNT; i++) {
 		u32 start, isr;
 
 		start = advk_readl(pcie, PIO_START);
 		isr = advk_readl(pcie, PIO_ISR);
 		if (!start && isr)
 			return 0;
+		udelay(PIO_RETRY_DELAY);
 	}
 
-	dev_err(dev, "config read/write timed out\n");
+	dev_err(dev, "PIO read/write transfer time out\n");
 	return -ETIMEDOUT;
 }
 
@@ -415,7 +477,7 @@
 
 	case PCI_EXP_RTCTL: {
 		u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG);
-		*value = (val & PCIE_MSG_PM_PME_MASK) ? PCI_EXP_RTCTL_PMEIE : 0;
+		*value = (val & PCIE_MSG_PM_PME_MASK) ? 0 : PCI_EXP_RTCTL_PMEIE;
 		return PCI_BRIDGE_EMUL_HANDLED;
 	}
 
@@ -426,11 +488,20 @@
 		return PCI_BRIDGE_EMUL_HANDLED;
 	}
 
+	case PCI_EXP_LNKCTL: {
+		/* u32 contains both PCI_EXP_LNKCTL and PCI_EXP_LNKSTA */
+		u32 val = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg) &
+			~(PCI_EXP_LNKSTA_LT << 16);
+		if (!advk_pcie_link_up(pcie))
+			val |= (PCI_EXP_LNKSTA_LT << 16);
+		*value = val;
+		return PCI_BRIDGE_EMUL_HANDLED;
+	}
+
 	case PCI_CAP_LIST_ID:
 	case PCI_EXP_DEVCAP:
 	case PCI_EXP_DEVCTL:
 	case PCI_EXP_LNKCAP:
-	case PCI_EXP_LNKCTL:
 		*value = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg);
 		return PCI_BRIDGE_EMUL_HANDLED;
 	default:
@@ -447,15 +518,25 @@
 
 	switch (reg) {
 	case PCI_EXP_DEVCTL:
-	case PCI_EXP_LNKCTL:
 		advk_writel(pcie, new, PCIE_CORE_PCIEXP_CAP + reg);
 		break;
 
-	case PCI_EXP_RTCTL:
-		new = (new & PCI_EXP_RTCTL_PMEIE) << 3;
-		advk_writel(pcie, new, PCIE_ISR0_MASK_REG);
+	case PCI_EXP_LNKCTL:
+		advk_writel(pcie, new, PCIE_CORE_PCIEXP_CAP + reg);
+		if (new & PCI_EXP_LNKCTL_RL)
+			advk_pcie_wait_for_retrain(pcie);
 		break;
 
+	case PCI_EXP_RTCTL: {
+		/* Only mask/unmask PME interrupt */
+		u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG) &
+			~PCIE_MSG_PM_PME_MASK;
+		if ((new & PCI_EXP_RTCTL_PMEIE) == 0)
+			val |= PCIE_MSG_PM_PME_MASK;
+		advk_writel(pcie, val, PCIE_ISR0_MASK_REG);
+		break;
+	}
+
 	case PCI_EXP_RTSTA:
 		new = (new & PCI_EXP_RTSTA_PME) >> 9;
 		advk_writel(pcie, new, PCIE_ISR0_REG);
@@ -475,7 +556,7 @@
  * Initialize the configuration space of the PCI-to-PCI bridge
  * associated with the given PCIe interface.
  */
-static void advk_sw_pci_bridge_init(struct advk_pcie *pcie)
+static int advk_sw_pci_bridge_init(struct advk_pcie *pcie)
 {
 	struct pci_bridge_emul *bridge = &pcie->bridge;
 
@@ -499,8 +580,7 @@
 	bridge->data = pcie;
 	bridge->ops = &advk_pci_bridge_emul_ops;
 
-	pci_bridge_emul_init(bridge, 0);
-
+	return pci_bridge_emul_init(bridge, 0);
 }
 
 static bool advk_pcie_valid_device(struct advk_pcie *pcie, struct pci_bus *bus,
@@ -512,6 +592,35 @@
 	return true;
 }
 
+static bool advk_pcie_pio_is_running(struct advk_pcie *pcie)
+{
+	struct device *dev = &pcie->pdev->dev;
+
+	/*
+	 * Trying to start a new PIO transfer when previous has not completed
+	 * cause External Abort on CPU which results in kernel panic:
+	 *
+	 *     SError Interrupt on CPU0, code 0xbf000002 -- SError
+	 *     Kernel panic - not syncing: Asynchronous SError Interrupt
+	 *
+	 * Functions advk_pcie_rd_conf() and advk_pcie_wr_conf() are protected
+	 * by raw_spin_lock_irqsave() at pci_lock_config() level to prevent
+	 * concurrent calls at the same time. But because PIO transfer may take
+	 * about 1.5s when link is down or card is disconnected, it means that
+	 * advk_pcie_wait_pio() does not always have to wait for completion.
+	 *
+	 * Some versions of ARM Trusted Firmware handles this External Abort at
+	 * EL3 level and mask it to prevent kernel panic. Relevant TF-A commit:
+	 * https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=3c7dcdac5c50
+	 */
+	if (advk_readl(pcie, PIO_START)) {
+		dev_err(dev, "Previous PIO read/write transfer is still running\n");
+		return true;
+	}
+
+	return false;
+}
+
 static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn,
 			     int where, int size, u32 *val)
 {
@@ -528,9 +637,10 @@
 		return pci_bridge_emul_conf_read(&pcie->bridge, where,
 						 size, val);
 
-	/* Start PIO */
-	advk_writel(pcie, 0, PIO_START);
-	advk_writel(pcie, 1, PIO_ISR);
+	if (advk_pcie_pio_is_running(pcie)) {
+		*val = 0xffffffff;
+		return PCIBIOS_SET_FAILED;
+	}
 
 	/* Program the control register */
 	reg = advk_readl(pcie, PIO_CTRL);
@@ -549,17 +659,21 @@
 	/* Program the data strobe */
 	advk_writel(pcie, 0xf, PIO_WR_DATA_STRB);
 
-	/* Start the transfer */
+	/* Clear PIO DONE ISR and start the transfer */
+	advk_writel(pcie, 1, PIO_ISR);
 	advk_writel(pcie, 1, PIO_START);
 
 	ret = advk_pcie_wait_pio(pcie);
 	if (ret < 0)
 		return PCIBIOS_SET_FAILED;
 
-	advk_pcie_check_pio_status(pcie);
+	/* Check PIO status and get the read result */
+	ret = advk_pcie_check_pio_status(pcie, val);
+	if (ret < 0) {
+		*val = 0xffffffff;
+		return PCIBIOS_SET_FAILED;
+	}
 
-	/* Get the read result */
-	*val = advk_readl(pcie, PIO_RD_DATA);
 	if (size == 1)
 		*val = (*val >> (8 * (where & 3))) & 0xff;
 	else if (size == 2)
@@ -587,9 +701,8 @@
 	if (where % size)
 		return PCIBIOS_SET_FAILED;
 
-	/* Start PIO */
-	advk_writel(pcie, 0, PIO_START);
-	advk_writel(pcie, 1, PIO_ISR);
+	if (advk_pcie_pio_is_running(pcie))
+		return PCIBIOS_SET_FAILED;
 
 	/* Program the control register */
 	reg = advk_readl(pcie, PIO_CTRL);
@@ -616,14 +729,17 @@
 	/* Program the data strobe */
 	advk_writel(pcie, data_strobe, PIO_WR_DATA_STRB);
 
-	/* Start the transfer */
+	/* Clear PIO DONE ISR and start the transfer */
+	advk_writel(pcie, 1, PIO_ISR);
 	advk_writel(pcie, 1, PIO_START);
 
 	ret = advk_pcie_wait_pio(pcie);
 	if (ret < 0)
 		return PCIBIOS_SET_FAILED;
 
-	advk_pcie_check_pio_status(pcie);
+	ret = advk_pcie_check_pio_status(pcie, NULL);
+	if (ret < 0)
+		return PCIBIOS_SET_FAILED;
 
 	return PCIBIOS_SUCCESSFUL;
 }
@@ -697,22 +813,28 @@
 {
 	struct advk_pcie *pcie = d->domain->host_data;
 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
+	unsigned long flags;
 	u32 mask;
 
+	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
 	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
 	mask |= PCIE_ISR1_INTX_ASSERT(hwirq);
 	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
+	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
 }
 
 static void advk_pcie_irq_unmask(struct irq_data *d)
 {
 	struct advk_pcie *pcie = d->domain->host_data;
 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
+	unsigned long flags;
 	u32 mask;
 
+	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
 	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
 	mask &= ~PCIE_ISR1_INTX_ASSERT(hwirq);
 	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
+	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
 }
 
 static int advk_pcie_irq_map(struct irq_domain *h,
@@ -796,6 +918,8 @@
 	struct irq_chip *irq_chip;
 	int ret = 0;
 
+	raw_spin_lock_init(&pcie->irq_lock);
+
 	pcie_intc_node =  of_get_next_child(node, NULL);
 	if (!pcie_intc_node) {
 		dev_err(dev, "No PCIe Intc node found\n");
@@ -999,7 +1123,11 @@
 
 	advk_pcie_setup_hw(pcie);
 
-	advk_sw_pci_bridge_init(pcie);
+	ret = advk_sw_pci_bridge_init(pcie);
+	if (ret) {
+		dev_err(dev, "Failed to register emulated root PCI bridge\n");
+		return ret;
+	}
 
 	ret = advk_pcie_init_irq_domain(pcie);
 	if (ret) {