From: Jay Dolan <jay.dolan@xxxxxxxxxxx>
The Pericom chips can achieve additional baud rates by programming the
sample clock register. The baud rates can be described as
921600 * 16 / (16 - scr) for scr values 5 to 15. The divisor is set to 1
for these baud rates.
Added pericom_do_set_divisor() to set higher baud rates and pass to
serial8250_do_set_divisor() for already supported rates
Pericom chips now use one of two pci quirks. The four port chips need to
set their fourth port at the correct address in addition to setting the
port.set_divisor pointer
Signed-off-by: Jay Dolan <jay.dolan@xxxxxxxxxxx>
---
drivers/tty/serial/8250/8250_pci.c | 66 +++++++++++++++++++++--------
drivers/tty/serial/8250/8250_port.c | 32 ++++++++++++++
include/linux/serial_8250.h | 3 ++
include/uapi/linux/serial_reg.h | 13 ++++--
4 files changed, 93 insertions(+), 21 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index df41397de478..8f86f5e578ff 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1333,6 +1333,30 @@ static int pci_pericom_setup(struct serial_private *priv,
{
unsigned int bar, offset = board->first_offset, maxnr;
+ bar = FL_GET_BASE(board->flags);
+ if (board->flags & FL_BASE_BARS)
+ bar += idx;
+ else
+ offset += idx * board->uart_offset;
+
+
+ maxnr = (pci_resource_len(priv->dev, bar) - board->first_offset) >>
+ (board->reg_shift + 3);
+
+ if (board->flags & FL_REGION_SZ_CAP && idx >= maxnr)
+ return 1;
+
+ port->port.set_divisor = pericom_do_set_divisor;
+
+ return setup_port(priv, port, bar, offset, board->reg_shift);
+}
+
+static int pci_pericom_setup_four_at_eight(struct serial_private *priv,
+ const struct pciserial_board *board,
+ struct uart_8250_port *port, int idx)
+{
+ unsigned int bar, offset = board->first_offset, maxnr;
+
bar = FL_GET_BASE(board->flags);
if (board->flags & FL_BASE_BARS)
bar += idx;
@@ -1348,6 +1372,8 @@ static int pci_pericom_setup(struct serial_private *priv,
if (board->flags & FL_REGION_SZ_CAP && idx >= maxnr)
return 1;
+ port->port.set_divisor = pericom_do_set_divisor;
+
return setup_port(priv, port, bar, offset, board->reg_shift);
}
@@ -1995,7 +2021,7 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
.device = PCI_DEVICE_ID_PERICOM_PI7C9X7954,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
/*
* PLX
@@ -2032,107 +2058,113 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
.device = PCI_DEVICE_ID_ACCESIO_PCIE_COM_4SDB,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_MPCIE_COM_4S,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_PCIE_COM232_4DB,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_MPCIE_COM232_4,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_PCIE_COM_4SMDB,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_MPCIE_COM_4SM,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_MPCIE_ICM422_4,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_MPCIE_ICM485_4,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_DEVICE_ID_ACCESIO_PCIE_ICM_4S,
.device = PCI_DEVICE_ID_ACCESIO_PCIE_ICM232_4,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_MPCIE_ICM232_4,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_PCIE_COM422_4,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_PCIE_COM485_4,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_PCIE_COM232_4,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_PCIE_COM_4SM,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
{
.vendor = PCI_VENDOR_ID_ACCESIO,
.device = PCI_DEVICE_ID_ACCESIO_PCIE_ICM_4SM,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
- .setup = pci_pericom_setup,
+ .setup = pci_pericom_setup_four_at_eight,
},
- /*
+ {
+ .vendor = PCI_VENDOR_ID_ACCESIO,
+ .device = PCI_ANY_ID,
+ .subvendor = PCI_ANY_ID,
+ .subdevice = PCI_ANY_ID,
+ .setup = pci_pericom_setup,
+ }, /*
* SBS Technologies, Inc., PMC-OCTALPRO 232
*/
{
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index d2f3310abe54..4b72f6ee7972 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2577,6 +2577,38 @@ static unsigned char serial8250_compute_lcr(struct uart_8250_port *up,
return cval;
}
+void
+pericom_do_set_divisor(struct uart_port *port, unsigned int baud,
+ unsigned int quot, unsigned int quot_frac)
+{
+ int scr;
+ int lcr;
+ int actual_baud;
+ int tolerance;
+
+ for (scr = 5 ; scr <= 15 ; scr++) {
+ actual_baud = 921600 * 16 / scr;
+ tolerance = actual_baud / 50;
+
+ if ((baud < actual_baud + tolerance) &&
+ (baud > actual_baud - tolerance)) {
+
+ lcr = serial_port_in(port, UART_LCR);
+ serial_port_out(port, UART_LCR, lcr | 0x80);
+
+ serial_port_out(port, UART_DLL, 1);
+ serial_port_out(port, UART_DLM, 0);
+ serial_port_out(port, UART_PCM_SCR, 16 - scr);
+ serial_port_out(port, UART_LCR, lcr);
+ return;
+ } else if (baud > actual_baud) {
+ break;
+ }
+ }
+ serial8250_do_set_divisor(port, baud, quot, quot_frac);
+}
+EXPORT_SYMBOL_GPL(pericom_do_set_divisor);
+
void serial8250_do_set_divisor(struct uart_port *port, unsigned int baud,
unsigned int quot, unsigned int quot_frac)
{
diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 5a655ba8d273..b5469563271f 100644
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -167,6 +167,9 @@ extern void serial8250_do_set_mctrl(struct uart_port *port, unsigned int mctrl);
extern void serial8250_do_set_divisor(struct uart_port *port, unsigned int baud,
unsigned int quot,
unsigned int quot_frac);
+extern void pericom_do_set_divisor(struct uart_port *port, unsigned int baud,
+ unsigned int quot,
+ unsigned int quot_frac);
extern int fsl8250_handle_irq(struct uart_port *port);
int serial8250_handle_irq(struct uart_port *port, unsigned int iir);
unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr);
diff --git a/include/uapi/linux/serial_reg.h b/include/uapi/linux/serial_reg.h
index be07b5470f4b..336147e72655 100644
--- a/include/uapi/linux/serial_reg.h
+++ b/include/uapi/linux/serial_reg.h
@@ -3,10 +3,10 @@
* include/linux/serial_reg.h
*
* Copyright (C) 1992, 1994 by Theodore Ts'o.
- *
- * Redistribution of this file is permitted under the terms of the GNU
+ *
+ * Redistribution of this file is permitted under the terms of the GNU
* Public License (GPL)
- *
+ *
* These are the UART port assignments, expressed as offsets from the base
* register. These assignments should hold for any serial port based on
* a 8250, 16450, or 16550(A).
@@ -97,7 +97,7 @@
#define UART_LCR 3 /* Out: Line Control Register */
/*
- * Note: if the word length is 5 bits (UART_LCR_WLEN5), then setting
+ * Note: if the word length is 5 bits (UART_LCR_WLEN5), then setting
* UART_LCR_STOP will select 1.5 stop bits, not 2 stop bits.
*/
#define UART_LCR_DLAB 0x80 /* Divisor latch access bit */
@@ -376,5 +376,10 @@
#define UART_ALTR_EN_TXFIFO_LW 0x01 /* Enable the TX FIFO Low Watermark */
#define UART_ALTR_TX_LOW 0x41 /* Tx FIFO Low Watermark */
+/*
+ * Definition for Pericom sample clock register
+ */
+#define UART_PCM_SCR 0x02 /*Sample Clock Register*/
+
#endif /* _LINUX_SERIAL_REG_H */
--
2.17.1
