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Merge of master.kernel.org:/home/rmk/linux-2.6-serial.git

This commit is contained in:
Linus Torvalds 2005-04-29 15:08:34 -07:00
parent dd96a8e056 587897f51f
commit a6ad57fb4b
1 changed files with 60 additions and 8 deletions
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68
drivers/serial/imx.c
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@ -321,18 +321,39 @@ static void imx_break_ctl(struct uart_port *port, int break_state)
#define TXTL 2 /* reset default */
#define RXTL 1 /* reset default */
static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
{
unsigned int val;
unsigned int ufcr_rfdiv;
/* set receiver / transmitter trigger level.
* RFDIV is set such way to satisfy requested uartclk value
*/
val = TXTL<<10 | RXTL;
ufcr_rfdiv = (imx_get_perclk1() + sport->port.uartclk / 2) / sport->port.uartclk;
if(!ufcr_rfdiv)
ufcr_rfdiv = 1;
if(ufcr_rfdiv >= 7)
ufcr_rfdiv = 6;
else
ufcr_rfdiv = 6 - ufcr_rfdiv;
val |= UFCR_RFDIV & (ufcr_rfdiv << 7);
UFCR((u32)sport->port.membase) = val;
return 0;
}
static int imx_startup(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
int retval;
unsigned int val;
unsigned long flags;
/* set receiver / transmitter trigger level. We assume
* that RFDIV has been set by the arch setup or by the bootloader.
*/
val = (UFCR((u32)sport->port.membase) & UFCR_RFDIV) | TXTL<<10 | RXTL;
UFCR((u32)sport->port.membase) = val;
imx_setup_ufcr(sport, 0);
/* disable the DREN bit (Data Ready interrupt enable) before
* requesting IRQs
@ -737,9 +758,12 @@ static void __init
imx_console_get_options(struct imx_port *sport, int *baud,
int *parity, int *bits)
{
if ( UCR1((u32)sport->port.membase) | UCR1_UARTEN ) {
/* ok, the port was enabled */
unsigned int ucr2, ubir,ubmr, uartclk;
unsigned int baud_raw;
unsigned int ucfr_rfdiv;
ucr2 = UCR2((u32)sport->port.membase);
@ -758,9 +782,35 @@ imx_console_get_options(struct imx_port *sport, int *baud,
ubir = UBIR((u32)sport->port.membase) & 0xffff;
ubmr = UBMR((u32)sport->port.membase) & 0xffff;
uartclk = sport->port.uartclk;
*baud = ((uartclk/16) * (ubir + 1)) / (ubmr + 1);
ucfr_rfdiv = (UFCR((u32)sport->port.membase) & UFCR_RFDIV) >> 7;
if (ucfr_rfdiv == 6)
ucfr_rfdiv = 7;
else
ucfr_rfdiv = 6 - ucfr_rfdiv;
uartclk = imx_get_perclk1();
uartclk /= ucfr_rfdiv;
{ /*
* The next code provides exact computation of
* baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
* without need of float support or long long division,
* which would be required to prevent 32bit arithmetic overflow
*/
unsigned int mul = ubir + 1;
unsigned int div = 16 * (ubmr + 1);
unsigned int rem = uartclk % div;
baud_raw = (uartclk / div) * mul;
baud_raw += (rem * mul + div / 2) / div;
*baud = (baud_raw + 50) / 100 * 100;
}
if(*baud != baud_raw)
printk(KERN_INFO "Serial: Console IMX rounded baud rate from %d to %d\n",
baud_raw, *baud);
}
}
@ -787,6 +837,8 @@ imx_console_setup(struct console *co, char *options)
else
imx_console_get_options(sport, &baud, &parity, &bits);
imx_setup_ufcr(sport, 0);
return uart_set_options(&sport->port, co, baud, parity, bits, flow);
}