[PATCH 2/4] pch_uart: Add Fish River Island II uart clock quirks

From: Darren Hart
Date: Wed Feb 29 2012 - 13:26:48 EST


Add support for the Fish River Island II (FRI2) UART clock following the CM-iTC
quirk handling mechanism. Depending on the firmware installed on the device, the
FRI2 uses a 48MHz or a 64MHz UART clock. This is detected with DMI strings.

Add similar UART clock quirk handling to the pch_console_setup() function to
enable kernel messages on boards with non-standard UART clocks.

Per Alan's suggestion, abstract out UART clock selection into
pch_uart_get_uartclk() to avoid code duplication.

Signed-off-by: Darren Hart <dvhart@xxxxxxxxxxxxxxx>
CC: Tomoya MORINAGA <tomoya.rohm@xxxxxxxxx>
CC: Feng Tang <feng.tang@xxxxxxxxx>
CC: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
CC: Alan Cox <alan@xxxxxxxxxxxxxxx>
CC: linux-serial@xxxxxxxxxxxxxxx
---
drivers/tty/serial/pch_uart.c | 42 +++++++++++++++++++++++++++-------------
1 files changed, 28 insertions(+), 14 deletions(-)

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index c565817..3a2b0ae 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -203,7 +203,10 @@ enum {

#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)

-#define DEFAULT_UARTCLK 1843200 /* 1.8432MHz */
+#define DEFAULT_UARTCLK 1843200 /* 1.8432 MHz */
+#define CMITC_UARTCLK 192000000 /* 192.0000 MHz */
+#define FRI2_64_UARTCLK 64000000 /* 64.0000 MHz */
+#define FRI2_48_UARTCLK 48000000 /* 48.0000 MHz */

struct pch_uart_buffer {
unsigned char *buf;
@@ -292,6 +295,26 @@ static const int trigger_level_64[4] = { 1, 16, 32, 56 };
static const int trigger_level_16[4] = { 1, 4, 8, 14 };
static const int trigger_level_1[4] = { 1, 1, 1, 1 };

+/* Return UART clock, checking for board specific clocks. */
+static int pch_uart_get_uartclk(void)
+{
+ const char *cmp;
+
+ cmp = dmi_get_system_info(DMI_BOARD_NAME);
+ if (cmp && strstr(cmp, "CM-iTC"))
+ return CMITC_UARTCLK;
+
+ cmp = dmi_get_system_info(DMI_BIOS_VERSION);
+ if (cmp && strnstr(cmp, "FRI2", 4))
+ return FRI2_64_UARTCLK;
+
+ cmp = dmi_get_system_info(DMI_PRODUCT_NAME);
+ if (cmp && strstr(cmp, "Fish River Island II"))
+ return FRI2_48_UARTCLK;
+
+ return DEFAULT_UARTCLK;
+}
+
static void pch_uart_hal_request(struct pci_dev *pdev, int fifosize,
int uartclk)
{
@@ -1506,8 +1529,7 @@ static int __init pch_console_setup(struct console *co, char *options)
if (!port || (!port->iobase && !port->membase))
return -ENODEV;

- /* setup uartclock */
- port->uartclk = DEFAULT_UARTCLK;
+ port->uartclk = pch_uart_get_uartclk();

if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
@@ -1550,10 +1572,9 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
unsigned int iobase;
unsigned int mapbase;
unsigned char *rxbuf;
- int fifosize, uartclk;
+ int fifosize;
int port_type;
struct pch_uart_driver_data *board;
- const char *board_name;

board = &drv_dat[id->driver_data];
port_type = board->port_type;
@@ -1566,13 +1587,6 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
if (!rxbuf)
goto init_port_free_txbuf;

- uartclk = DEFAULT_UARTCLK;
-
- /* quirk for CM-iTC board */
- board_name = dmi_get_system_info(DMI_BOARD_NAME);
- if (board_name && strstr(board_name, "CM-iTC"))
- uartclk = 192000000; /* 192.0MHz */
-
switch (port_type) {
case PORT_UNKNOWN:
fifosize = 256; /* EG20T/ML7213: UART0 */
@@ -1597,7 +1611,7 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
priv->rxbuf.size = PAGE_SIZE;

priv->fifo_size = fifosize;
- priv->uartclk = uartclk;
+ priv->uartclk = pch_uart_get_uartclk();
priv->port_type = PORT_MAX_8250 + port_type + 1;
priv->port.dev = &pdev->dev;
priv->port.iobase = iobase;
@@ -1614,7 +1628,7 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
spin_lock_init(&priv->port.lock);

pci_set_drvdata(pdev, priv);
- pch_uart_hal_request(pdev, fifosize, uartclk);
+ pch_uart_hal_request(pdev, fifosize, priv->uartclk);

#ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
pch_uart_ports[board->line_no] = priv;
--
1.7.6.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/