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sparc32,leon: Fixed APBUART frequency detection

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The UARTs may be located on different APB buses, thus have

different UART clock frequency. The system frequency is not
the same (but often) as the UART frequency, rather the APB bus
frequency that the APBUART is located at has the same
frequency, so this looks at the "freq" property instead.

Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Daniel Hellstrom 2011-03-30 01:12:41 +00:00 committed by David S. Miller
parent 10544f128c
commit c897dcf631
1 changed files with 7 additions and 17 deletions
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24
drivers/tty/serial/apbuart.c
View file

@ -598,24 +598,12 @@ static struct platform_driver grlib_apbuart_of_driver = {
static int grlib_apbuart_configure(void)
{
struct device_node *np, *rp;
const u32 *prop;
int freq_khz, line = 0;
/* Get bus frequency */
rp = of_find_node_by_path("/");
if (!rp)
return -ENODEV;
rp = of_get_next_child(rp, NULL);
if (!rp)
return -ENODEV;
prop = of_get_property(rp, "clock-frequency", NULL);
if (!prop)
return -ENODEV;
freq_khz = *prop;
struct device_node *np;
int line = 0;
for_each_matching_node(np, apbuart_match) {
const int *ampopts;
const u32 *freq_hz;
const struct amba_prom_registers *regs;
struct uart_port *port;
unsigned long addr;
@ -624,8 +612,10 @@ static int grlib_apbuart_configure(void)
if (ampopts && (*ampopts == 0))
continue; /* Ignore if used by another OS instance */
regs = of_get_property(np, "reg", NULL);
/* Frequency of APB Bus is frequency of UART */
freq_hz = of_get_property(np, "freq", NULL);
if (!regs)
if (!regs || !freq_hz || (*freq_hz == 0))
continue;
grlib_apbuart_nodes[line] = np;
@ -641,7 +631,7 @@ static int grlib_apbuart_configure(void)
port->ops = &grlib_apbuart_ops;
port->flags = UPF_BOOT_AUTOCONF;
port->line = line;
port->uartclk = freq_khz * 1000;
port->uartclk = *freq_hz;
port->fifosize = apbuart_scan_fifo_size((struct uart_port *) port, line);
line++;