linux/drivers/ssb/driver_extif.c
Hauke Mehrtens 394bc7e38b ssb: add locking around gpio register accesses
The GPIOs are access through some registers in the chip common core or
over extif. We need locking around these GPIO accesses, all GPIOs are
accessed through the same registers and parallel writes will cause
problems.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: http://patchwork.linux-mips.org/patch/4590
Acked-by: Florian Fainelli <florian@openwrt.org>
2012-11-21 21:55:52 +01:00

182 lines
4.5 KiB
C

/*
* Sonics Silicon Backplane
* Broadcom EXTIF core driver
*
* Copyright 2005, Broadcom Corporation
* Copyright 2006, 2007, Michael Buesch <m@bues.ch>
* Copyright 2006, 2007, Felix Fietkau <nbd@openwrt.org>
* Copyright 2007, Aurelien Jarno <aurelien@aurel32.net>
*
* Licensed under the GNU/GPL. See COPYING for details.
*/
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/serial_reg.h>
#include "ssb_private.h"
static inline u32 extif_read32(struct ssb_extif *extif, u16 offset)
{
return ssb_read32(extif->dev, offset);
}
static inline void extif_write32(struct ssb_extif *extif, u16 offset, u32 value)
{
ssb_write32(extif->dev, offset, value);
}
static inline u32 extif_write32_masked(struct ssb_extif *extif, u16 offset,
u32 mask, u32 value)
{
value &= mask;
value |= extif_read32(extif, offset) & ~mask;
extif_write32(extif, offset, value);
return value;
}
#ifdef CONFIG_SSB_SERIAL
static bool serial_exists(u8 *regs)
{
u8 save_mcr, msr = 0;
if (regs) {
save_mcr = regs[UART_MCR];
regs[UART_MCR] = (UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_RTS);
msr = regs[UART_MSR] & (UART_MSR_DCD | UART_MSR_RI
| UART_MSR_CTS | UART_MSR_DSR);
regs[UART_MCR] = save_mcr;
}
return (msr == (UART_MSR_DCD | UART_MSR_CTS));
}
int ssb_extif_serial_init(struct ssb_extif *extif, struct ssb_serial_port *ports)
{
u32 i, nr_ports = 0;
/* Disable GPIO interrupt initially */
extif_write32(extif, SSB_EXTIF_GPIO_INTPOL, 0);
extif_write32(extif, SSB_EXTIF_GPIO_INTMASK, 0);
for (i = 0; i < 2; i++) {
void __iomem *uart_regs;
uart_regs = ioremap_nocache(SSB_EUART, 16);
if (uart_regs) {
uart_regs += (i * 8);
if (serial_exists(uart_regs) && ports) {
extif_write32(extif, SSB_EXTIF_GPIO_INTMASK, 2);
nr_ports++;
ports[i].regs = uart_regs;
ports[i].irq = 2;
ports[i].baud_base = 13500000;
ports[i].reg_shift = 0;
}
iounmap(uart_regs);
}
}
return nr_ports;
}
#endif /* CONFIG_SSB_SERIAL */
void ssb_extif_timing_init(struct ssb_extif *extif, unsigned long ns)
{
u32 tmp;
/* Initialize extif so we can get to the LEDs and external UART */
extif_write32(extif, SSB_EXTIF_PROG_CFG, SSB_EXTCFG_EN);
/* Set timing for the flash */
tmp = DIV_ROUND_UP(10, ns) << SSB_PROG_WCNT_3_SHIFT;
tmp |= DIV_ROUND_UP(40, ns) << SSB_PROG_WCNT_1_SHIFT;
tmp |= DIV_ROUND_UP(120, ns);
extif_write32(extif, SSB_EXTIF_PROG_WAITCNT, tmp);
/* Set programmable interface timing for external uart */
tmp = DIV_ROUND_UP(10, ns) << SSB_PROG_WCNT_3_SHIFT;
tmp |= DIV_ROUND_UP(20, ns) << SSB_PROG_WCNT_2_SHIFT;
tmp |= DIV_ROUND_UP(100, ns) << SSB_PROG_WCNT_1_SHIFT;
tmp |= DIV_ROUND_UP(120, ns);
extif_write32(extif, SSB_EXTIF_PROG_WAITCNT, tmp);
}
void ssb_extif_get_clockcontrol(struct ssb_extif *extif,
u32 *pll_type, u32 *n, u32 *m)
{
*pll_type = SSB_PLLTYPE_1;
*n = extif_read32(extif, SSB_EXTIF_CLOCK_N);
*m = extif_read32(extif, SSB_EXTIF_CLOCK_SB);
}
void ssb_extif_watchdog_timer_set(struct ssb_extif *extif,
u32 ticks)
{
extif_write32(extif, SSB_EXTIF_WATCHDOG, ticks);
}
void ssb_extif_init(struct ssb_extif *extif)
{
if (!extif->dev)
return; /* We don't have a Extif core */
spin_lock_init(&extif->gpio_lock);
}
u32 ssb_extif_gpio_in(struct ssb_extif *extif, u32 mask)
{
return extif_read32(extif, SSB_EXTIF_GPIO_IN) & mask;
}
u32 ssb_extif_gpio_out(struct ssb_extif *extif, u32 mask, u32 value)
{
unsigned long flags;
u32 res = 0;
spin_lock_irqsave(&extif->gpio_lock, flags);
res = extif_write32_masked(extif, SSB_EXTIF_GPIO_OUT(0),
mask, value);
spin_unlock_irqrestore(&extif->gpio_lock, flags);
return res;
}
u32 ssb_extif_gpio_outen(struct ssb_extif *extif, u32 mask, u32 value)
{
unsigned long flags;
u32 res = 0;
spin_lock_irqsave(&extif->gpio_lock, flags);
res = extif_write32_masked(extif, SSB_EXTIF_GPIO_OUTEN(0),
mask, value);
spin_unlock_irqrestore(&extif->gpio_lock, flags);
return res;
}
u32 ssb_extif_gpio_polarity(struct ssb_extif *extif, u32 mask, u32 value)
{
unsigned long flags;
u32 res = 0;
spin_lock_irqsave(&extif->gpio_lock, flags);
res = extif_write32_masked(extif, SSB_EXTIF_GPIO_INTPOL, mask, value);
spin_unlock_irqrestore(&extif->gpio_lock, flags);
return res;
}
u32 ssb_extif_gpio_intmask(struct ssb_extif *extif, u32 mask, u32 value)
{
unsigned long flags;
u32 res = 0;
spin_lock_irqsave(&extif->gpio_lock, flags);
res = extif_write32_masked(extif, SSB_EXTIF_GPIO_INTMASK, mask, value);
spin_unlock_irqrestore(&extif->gpio_lock, flags);
return res;
}