diff options
Diffstat (limited to 'kernel/arch/powerpc/boot/mpc52xx-psc.c')
-rw-r--r-- | kernel/arch/powerpc/boot/mpc52xx-psc.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/boot/mpc52xx-psc.c b/kernel/arch/powerpc/boot/mpc52xx-psc.c new file mode 100644 index 000000000..d4cb4e4e0 --- /dev/null +++ b/kernel/arch/powerpc/boot/mpc52xx-psc.c @@ -0,0 +1,64 @@ +/* + * MPC5200 PSC serial console support. + * + * Author: Grant Likely <grant.likely@secretlab.ca> + * + * Copyright (c) 2007 Secret Lab Technologies Ltd. + * Copyright (c) 2007 Freescale Semiconductor, Inc. + * + * It is assumed that the firmware (or the platform file) has already set + * up the port. + */ + +#include "types.h" +#include "io.h" +#include "ops.h" + +/* Programmable Serial Controller (PSC) status register bits */ +#define MPC52xx_PSC_SR 0x04 +#define MPC52xx_PSC_SR_RXRDY 0x0100 +#define MPC52xx_PSC_SR_RXFULL 0x0200 +#define MPC52xx_PSC_SR_TXRDY 0x0400 +#define MPC52xx_PSC_SR_TXEMP 0x0800 + +#define MPC52xx_PSC_BUFFER 0x0C + +static void *psc; + +static int psc_open(void) +{ + /* Assume the firmware has already configured the PSC into + * uart mode */ + return 0; +} + +static void psc_putc(unsigned char c) +{ + while (!(in_be16(psc + MPC52xx_PSC_SR) & MPC52xx_PSC_SR_TXRDY)) ; + out_8(psc + MPC52xx_PSC_BUFFER, c); +} + +static unsigned char psc_tstc(void) +{ + return (in_be16(psc + MPC52xx_PSC_SR) & MPC52xx_PSC_SR_RXRDY) != 0; +} + +static unsigned char psc_getc(void) +{ + while (!(in_be16(psc + MPC52xx_PSC_SR) & MPC52xx_PSC_SR_RXRDY)) ; + return in_8(psc + MPC52xx_PSC_BUFFER); +} + +int mpc5200_psc_console_init(void *devp, struct serial_console_data *scdp) +{ + /* Get the base address of the psc registers */ + if (dt_get_virtual_reg(devp, &psc, 1) < 1) + return -1; + + scdp->open = psc_open; + scdp->putc = psc_putc; + scdp->getc = psc_getc; + scdp->tstc = psc_tstc; + + return 0; +} |