Upgrade to 4.4.50-rt62

The current kernel is based on rt kernel v4.4.6-rt14. We will upgrade it
to 4.4.50-rt62.
The command to achieve it is:
a) Clone a git repo from
git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git

b) Get the diff between this two changesets:
git diff 640eca2901f3435e616157b11379d3223a44b391
705619beeea1b0b48219a683fd1a901a86fdaf5e

where the two commits are:
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
640eca2901f3435e616157b11379d3223a44b391
640eca2901f3 v4.4.6-rt14
localversion-rt
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
705619beeea1b0b48219a683fd1a901a86fdaf5e
705619beeea1 Linux 4.4.50-rt62
localversion-rt

c) One patch has been backported thus revert the patch before applying.

 filterdiff -p1 -x scripts/package/Makefile
~/tmp/v4.4.6-rt14-4.4.50-rt62.diff  |patch -p1 --dry-run

Upstream status: backport

Change-Id: I244d57a32f6066e5a5b9915f9fbf99e7bbca6e01
Signed-off-by: Yunhong Jiang <yunhong.jiang@linux.intel.com>

1 files changed, 25 insertions, 13 deletions

diff --git a/kernel/drivers/tty/serial/8250/8250_mid.c b/kernel/drivers/tty/serial/8250/8250_mid.c
index 88531a36b..83b3988eb 100644
--- a/kernel/drivers/tty/serial/8250/8250_mid.c
+++ b/kernel/drivers/tty/serial/8250/8250_mid.c
@@ -14,6 +14,7 @@
 #include <linux/pci.h>
 
 #include <linux/dma/hsu.h>
+#include <linux/8250_pci.h>
 
 #include "8250.h"
 
@@ -24,6 +25,7 @@
 #define PCI_DEVICE_ID_INTEL_DNV_UART	0x19d8
 
 /* Intel MID Specific registers */
+#define INTEL_MID_UART_DNV_FISR		0x08
 #define INTEL_MID_UART_PS		0x30
 #define INTEL_MID_UART_MUL		0x34
 #define INTEL_MID_UART_DIV		0x38
@@ -31,6 +33,7 @@
 struct mid8250;
 
 struct mid8250_board {
+	unsigned int flags;
 	unsigned long freq;
 	unsigned int base_baud;
 	int (*setup)(struct mid8250 *, struct uart_port *p);
@@ -88,16 +91,16 @@ static int tng_setup(struct mid8250 *mid, struct uart_port *p)
 static int dnv_handle_irq(struct uart_port *p)
 {
 	struct mid8250 *mid = p->private_data;
-	int ret;
-
-	ret = hsu_dma_irq(&mid->dma_chip, 0);
-	ret |= hsu_dma_irq(&mid->dma_chip, 1);
-
-	/* For now, letting the HW generate separate interrupt for the UART */
-	if (ret)
-		return ret;
-
-	return serial8250_handle_irq(p, serial_port_in(p, UART_IIR));
+	unsigned int fisr = serial_port_in(p, INTEL_MID_UART_DNV_FISR);
+	int ret = IRQ_NONE;
+
+	if (fisr & BIT(2))
+		ret |= hsu_dma_irq(&mid->dma_chip, 1);
+	if (fisr & BIT(1))
+		ret |= hsu_dma_irq(&mid->dma_chip, 0);
+	if (fisr & BIT(0))
+		ret |= serial8250_handle_irq(p, serial_port_in(p, UART_IIR));
+	return ret;
 }
 
 #define DNV_DMA_CHAN_OFFSET 0x80
@@ -106,12 +109,13 @@ static int dnv_setup(struct mid8250 *mid, struct uart_port *p)
 {
 	struct hsu_dma_chip *chip = &mid->dma_chip;
 	struct pci_dev *pdev = to_pci_dev(p->dev);
+	unsigned int bar = FL_GET_BASE(mid->board->flags);
 	int ret;
 
 	chip->dev = &pdev->dev;
 	chip->irq = pdev->irq;
 	chip->regs = p->membase;
-	chip->length = pci_resource_len(pdev, 0);
+	chip->length = pci_resource_len(pdev, bar);
 	chip->offset = DNV_DMA_CHAN_OFFSET;
 
 	/* Falling back to PIO mode if DMA probing fails */
@@ -145,6 +149,9 @@ static void mid8250_set_termios(struct uart_port *p,
 	unsigned long w = BIT(24) - 1;
 	unsigned long mul, div;
 
+	/* Gracefully handle the B0 case: fall back to B9600 */
+	fuart = fuart ? fuart : 9600 * 16;
+
 	if (mid->board->freq < fuart) {
 		/* Find prescaler value that satisfies Fuart < Fref */
 		if (mid->board->freq > baud)
@@ -217,6 +224,7 @@ static int mid8250_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	struct uart_8250_port uart;
 	struct mid8250 *mid;
+	unsigned int bar;
 	int ret;
 
 	ret = pcim_enable_device(pdev);
@@ -230,6 +238,7 @@ static int mid8250_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		return -ENOMEM;
 
 	mid->board = (struct mid8250_board *)id->driver_data;
+	bar = FL_GET_BASE(mid->board->flags);
 
 	memset(&uart, 0, sizeof(struct uart_8250_port));
 
@@ -242,8 +251,8 @@ static int mid8250_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	uart.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT | UPF_FIXED_TYPE;
 	uart.port.set_termios = mid8250_set_termios;
 
-	uart.port.mapbase = pci_resource_start(pdev, 0);
-	uart.port.membase = pcim_iomap(pdev, 0, 0);
+	uart.port.mapbase = pci_resource_start(pdev, bar);
+	uart.port.membase = pcim_iomap(pdev, bar, 0);
 	if (!uart.port.membase)
 		return -ENOMEM;
 
@@ -282,18 +291,21 @@ static void mid8250_remove(struct pci_dev *pdev)
 }
 
 static const struct mid8250_board pnw_board = {
+	.flags = FL_BASE0,
 	.freq = 50000000,
 	.base_baud = 115200,
 	.setup = pnw_setup,
 };
 
 static const struct mid8250_board tng_board = {
+	.flags = FL_BASE0,
 	.freq = 38400000,
 	.base_baud = 1843200,
 	.setup = tng_setup,
 };
 
 static const struct mid8250_board dnv_board = {
+	.flags = FL_BASE1,
 	.freq = 133333333,
 	.base_baud = 115200,
 	.setup = dnv_setup,