On most x86 boards, the legacy serial ports (io address 0x3f8/0x2f8) are provided by a superio chip connected to the LPC bus. We must program the superio chip so that serial ports are available for us.
Signed-off-by: Bin Meng bmeng.cn@gmail.com
---
Changes in v2: - Add a comment to describe PNP_DEV - Change pnp device inline routine parameters to use proper size
arch/x86/include/asm/pnp_def.h | 90 ++++++++++++++++++++++++++++++++++++++++++ drivers/misc/Makefile | 1 + drivers/misc/smsc_lpc47m.c | 33 ++++++++++++++++ include/smsc_lpc47m.h | 19 +++++++++ 4 files changed, 143 insertions(+) create mode 100644 arch/x86/include/asm/pnp_def.h create mode 100644 drivers/misc/smsc_lpc47m.c create mode 100644 include/smsc_lpc47m.h
diff --git a/arch/x86/include/asm/pnp_def.h b/arch/x86/include/asm/pnp_def.h new file mode 100644 index 0000000..24b038d --- /dev/null +++ b/arch/x86/include/asm/pnp_def.h @@ -0,0 +1,90 @@ +/* + * Copyright (C) 2014, Bin Meng bmeng.cn@gmail.com + * + * Adapted from coreboot src/include/device/pnp_def.h + * and arch/x86/include/arch/io.h + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef _ASM_PNP_DEF_H_ +#define _ASM_PNP_DEF_H_ + +#include <asm/io.h> + +#define PNP_IDX_EN 0x30 +#define PNP_IDX_IO0 0x60 +#define PNP_IDX_IO1 0x62 +#define PNP_IDX_IO2 0x64 +#define PNP_IDX_IO3 0x66 +#define PNP_IDX_IRQ0 0x70 +#define PNP_IDX_IRQ1 0x72 +#define PNP_IDX_DRQ0 0x74 +#define PNP_IDX_DRQ1 0x75 +#define PNP_IDX_MSC0 0xf0 +#define PNP_IDX_MSC1 0xf1 + +/* Generic functions for pnp devices */ + +/* + * pnp device is a 16-bit integer composed of its i/o port address at high byte + * and logic function number at low byte. + */ +#define PNP_DEV(PORT, FUNC) (((PORT) << 8) | (FUNC)) + +static inline void pnp_write_config(uint16_t dev, uint8_t reg, uint8_t value) +{ + uint8_t port = dev >> 8; + + outb(reg, port); + outb(value, port + 1); +} + +static inline uint8_t pnp_read_config(uint16_t dev, uint8_t reg) +{ + uint8_t port = dev >> 8; + + outb(reg, port); + return inb(port + 1); +} + +static inline void pnp_set_logical_device(uint16_t dev) +{ + uint8_t device = dev & 0xff; + + pnp_write_config(dev, 0x07, device); +} + +static inline void pnp_set_enable(uint16_t dev, int enable) +{ + pnp_write_config(dev, PNP_IDX_EN, enable ? 1 : 0); +} + +static inline int pnp_read_enable(uint16_t dev) +{ + return !!pnp_read_config(dev, PNP_IDX_EN); +} + +static inline void pnp_set_iobase(uint16_t dev, uint8_t index, uint16_t iobase) +{ + pnp_write_config(dev, index + 0, (iobase >> 8) & 0xff); + pnp_write_config(dev, index + 1, iobase & 0xff); +} + +static inline uint16_t pnp_read_iobase(uint16_t dev, uint8_t index) +{ + return ((uint16_t)(pnp_read_config(dev, index)) << 8) | + pnp_read_config(dev, index + 1); +} + +static inline void pnp_set_irq(uint16_t dev, uint8_t index, unsigned irq) +{ + pnp_write_config(dev, index, irq); +} + +static inline void pnp_set_drq(uint16_t dev, uint8_t index, unsigned drq) +{ + pnp_write_config(dev, index, drq & 0xff); +} + +#endif /* _ASM_PNP_DEF_H_ */ diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 2f2e48f..eb57497 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_MXC_OCOTP) += mxc_ocotp.o obj-$(CONFIG_MXS_OCOTP) += mxs_ocotp.o obj-$(CONFIG_NS87308) += ns87308.o obj-$(CONFIG_PDSP188x) += pdsp188x.o +obj-$(CONFIG_SMSC_LPC47M) += smsc_lpc47m.o obj-$(CONFIG_STATUS_LED) += status_led.o obj-$(CONFIG_TWL4030_LED) += twl4030_led.o obj-$(CONFIG_FSL_IFC) += fsl_ifc.o diff --git a/drivers/misc/smsc_lpc47m.c b/drivers/misc/smsc_lpc47m.c new file mode 100644 index 0000000..d51f8e3 --- /dev/null +++ b/drivers/misc/smsc_lpc47m.c @@ -0,0 +1,33 @@ +/* + * Copyright (C) 2014, Bin Meng bmeng.cn@gmail.com + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <asm/io.h> +#include <asm/pnp_def.h> + +static void pnp_enter_conf_state(u16 dev) +{ + u16 port = dev >> 8; + + outb(0x55, port); +} + +static void pnp_exit_conf_state(u16 dev) +{ + u16 port = dev >> 8; + + outb(0xaa, port); +} + +void lpc47m_enable_serial(u16 dev, u16 iobase) +{ + pnp_enter_conf_state(dev); + pnp_set_logical_device(dev); + pnp_set_enable(dev, 0); + pnp_set_iobase(dev, PNP_IDX_IO0, iobase); + pnp_set_enable(dev, 1); + pnp_exit_conf_state(dev); +} diff --git a/include/smsc_lpc47m.h b/include/smsc_lpc47m.h new file mode 100644 index 0000000..bffd622 --- /dev/null +++ b/include/smsc_lpc47m.h @@ -0,0 +1,19 @@ +/* + * Copyright (C) 2014, Bin Meng bmeng.cn@gmail.com + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef _SMSC_LPC47M_H_ +#define _SMSC_LPC47M_H_ + +/** + * Configure the base I/O port of the specified serial device and enable the + * serial device. + * + * @dev: High 8 bits = Super I/O port, low 8 bits = logical device number. + * @iobase: Processor I/O port address to assign to this serial device. + */ +void lpc47m_enable_serial(u16 dev, u16 iobase); + +#endif /* _SMSC_LPC47M_H_ */