u-boot/drivers/serial/ns16550.c
Stefan Roese 7fded0ce0f Revert "serial: ns16550: Add RX interrupt buffer support"
This reverts commit 6822cf3ec7.

As Bin Meng has tested and pointed out, we don't need the RX interrupt
for the RX buffer support at all. Just reading all available characters
into a buffer is sufficient to solve the problem with the dropped
characters upon long lines pasted into the U-Boot prompt. Since this
RX buffer support can be implemented in a generic way, without any
device specifica (e.g. for the ns16550), I'll post a new patch with
a new serial RX buffer support for DM, which all DM based serial
drivers can use.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Tom Rini <trini@konsulko.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2017-08-24 11:00:47 +08:00

514 lines
14 KiB
C

/*
* COM1 NS16550 support
* originally from linux source (arch/powerpc/boot/ns16550.c)
* modified to use CONFIG_SYS_ISA_MEM and new defines
*/
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <errno.h>
#include <ns16550.h>
#include <serial.h>
#include <watchdog.h>
#include <linux/types.h>
#include <asm/io.h>
DECLARE_GLOBAL_DATA_PTR;
#define UART_LCRVAL UART_LCR_8N1 /* 8 data, 1 stop, no parity */
#define UART_MCRVAL (UART_MCR_DTR | \
UART_MCR_RTS) /* RTS/DTR */
#ifndef CONFIG_DM_SERIAL
#ifdef CONFIG_SYS_NS16550_PORT_MAPPED
#define serial_out(x, y) outb(x, (ulong)y)
#define serial_in(y) inb((ulong)y)
#elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE > 0)
#define serial_out(x, y) out_be32(y, x)
#define serial_in(y) in_be32(y)
#elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE < 0)
#define serial_out(x, y) out_le32(y, x)
#define serial_in(y) in_le32(y)
#else
#define serial_out(x, y) writeb(x, y)
#define serial_in(y) readb(y)
#endif
#endif /* !CONFIG_DM_SERIAL */
#if defined(CONFIG_SOC_KEYSTONE)
#define UART_REG_VAL_PWREMU_MGMT_UART_DISABLE 0
#define UART_REG_VAL_PWREMU_MGMT_UART_ENABLE ((1 << 14) | (1 << 13) | (1 << 0))
#undef UART_MCRVAL
#ifdef CONFIG_SERIAL_HW_FLOW_CONTROL
#define UART_MCRVAL (UART_MCR_RTS | UART_MCR_AFE)
#else
#define UART_MCRVAL (UART_MCR_RTS)
#endif
#endif
#ifndef CONFIG_SYS_NS16550_IER
#define CONFIG_SYS_NS16550_IER 0x00
#endif /* CONFIG_SYS_NS16550_IER */
static inline void serial_out_shift(void *addr, int shift, int value)
{
#ifdef CONFIG_SYS_NS16550_PORT_MAPPED
outb(value, (ulong)addr);
#elif defined(CONFIG_SYS_NS16550_MEM32) && !defined(CONFIG_SYS_BIG_ENDIAN)
out_le32(addr, value);
#elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_BIG_ENDIAN)
out_be32(addr, value);
#elif defined(CONFIG_SYS_NS16550_MEM32)
writel(value, addr);
#elif defined(CONFIG_SYS_BIG_ENDIAN)
writeb(value, addr + (1 << shift) - 1);
#else
writeb(value, addr);
#endif
}
static inline int serial_in_shift(void *addr, int shift)
{
#ifdef CONFIG_SYS_NS16550_PORT_MAPPED
return inb((ulong)addr);
#elif defined(CONFIG_SYS_NS16550_MEM32) && !defined(CONFIG_SYS_BIG_ENDIAN)
return in_le32(addr);
#elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_BIG_ENDIAN)
return in_be32(addr);
#elif defined(CONFIG_SYS_NS16550_MEM32)
return readl(addr);
#elif defined(CONFIG_SYS_BIG_ENDIAN)
return readb(addr + (1 << shift) - 1);
#else
return readb(addr);
#endif
}
#ifdef CONFIG_DM_SERIAL
#ifndef CONFIG_SYS_NS16550_CLK
#define CONFIG_SYS_NS16550_CLK 0
#endif
static void ns16550_writeb(NS16550_t port, int offset, int value)
{
struct ns16550_platdata *plat = port->plat;
unsigned char *addr;
offset *= 1 << plat->reg_shift;
addr = (unsigned char *)plat->base + offset;
/*
* As far as we know it doesn't make sense to support selection of
* these options at run-time, so use the existing CONFIG options.
*/
serial_out_shift(addr + plat->reg_offset, plat->reg_shift, value);
}
static int ns16550_readb(NS16550_t port, int offset)
{
struct ns16550_platdata *plat = port->plat;
unsigned char *addr;
offset *= 1 << plat->reg_shift;
addr = (unsigned char *)plat->base + offset;
return serial_in_shift(addr + plat->reg_offset, plat->reg_shift);
}
static u32 ns16550_getfcr(NS16550_t port)
{
struct ns16550_platdata *plat = port->plat;
return plat->fcr;
}
/* We can clean these up once everything is moved to driver model */
#define serial_out(value, addr) \
ns16550_writeb(com_port, \
(unsigned char *)addr - (unsigned char *)com_port, value)
#define serial_in(addr) \
ns16550_readb(com_port, \
(unsigned char *)addr - (unsigned char *)com_port)
#else
static u32 ns16550_getfcr(NS16550_t port)
{
return UART_FCR_DEFVAL;
}
#endif
int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate)
{
const unsigned int mode_x_div = 16;
return DIV_ROUND_CLOSEST(clock, mode_x_div * baudrate);
}
static void NS16550_setbrg(NS16550_t com_port, int baud_divisor)
{
serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr);
serial_out(baud_divisor & 0xff, &com_port->dll);
serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm);
serial_out(UART_LCRVAL, &com_port->lcr);
}
void NS16550_init(NS16550_t com_port, int baud_divisor)
{
#if (defined(CONFIG_SPL_BUILD) && \
(defined(CONFIG_OMAP34XX) || defined(CONFIG_OMAP44XX)))
/*
* On some OMAP3/OMAP4 devices when UART3 is configured for boot mode
* before SPL starts only THRE bit is set. We have to empty the
* transmitter before initialization starts.
*/
if ((serial_in(&com_port->lsr) & (UART_LSR_TEMT | UART_LSR_THRE))
== UART_LSR_THRE) {
if (baud_divisor != -1)
NS16550_setbrg(com_port, baud_divisor);
serial_out(0, &com_port->mdr1);
}
#endif
while (!(serial_in(&com_port->lsr) & UART_LSR_TEMT))
;
serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
#if defined(CONFIG_ARCH_OMAP2PLUS)
serial_out(0x7, &com_port->mdr1); /* mode select reset TL16C750*/
#endif
serial_out(UART_MCRVAL, &com_port->mcr);
serial_out(ns16550_getfcr(com_port), &com_port->fcr);
if (baud_divisor != -1)
NS16550_setbrg(com_port, baud_divisor);
#if defined(CONFIG_ARCH_OMAP2PLUS) || defined(CONFIG_SOC_DA8XX)
/* /16 is proper to hit 115200 with 48MHz */
serial_out(0, &com_port->mdr1);
#endif
#if defined(CONFIG_SOC_KEYSTONE)
serial_out(UART_REG_VAL_PWREMU_MGMT_UART_ENABLE, &com_port->regC);
#endif
}
#ifndef CONFIG_NS16550_MIN_FUNCTIONS
void NS16550_reinit(NS16550_t com_port, int baud_divisor)
{
serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
NS16550_setbrg(com_port, 0);
serial_out(UART_MCRVAL, &com_port->mcr);
serial_out(ns16550_getfcr(com_port), &com_port->fcr);
NS16550_setbrg(com_port, baud_divisor);
}
#endif /* CONFIG_NS16550_MIN_FUNCTIONS */
void NS16550_putc(NS16550_t com_port, char c)
{
while ((serial_in(&com_port->lsr) & UART_LSR_THRE) == 0)
;
serial_out(c, &com_port->thr);
/*
* Call watchdog_reset() upon newline. This is done here in putc
* since the environment code uses a single puts() to print the complete
* environment upon "printenv". So we can't put this watchdog call
* in puts().
*/
if (c == '\n')
WATCHDOG_RESET();
}
#ifndef CONFIG_NS16550_MIN_FUNCTIONS
char NS16550_getc(NS16550_t com_port)
{
while ((serial_in(&com_port->lsr) & UART_LSR_DR) == 0) {
#if !defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_TTY)
extern void usbtty_poll(void);
usbtty_poll();
#endif
WATCHDOG_RESET();
}
return serial_in(&com_port->rbr);
}
int NS16550_tstc(NS16550_t com_port)
{
return (serial_in(&com_port->lsr) & UART_LSR_DR) != 0;
}
#endif /* CONFIG_NS16550_MIN_FUNCTIONS */
#ifdef CONFIG_DEBUG_UART_NS16550
#include <debug_uart.h>
static inline void _debug_uart_init(void)
{
struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
int baud_divisor;
/*
* We copy the code from above because it is already horribly messy.
* Trying to refactor to nicely remove the duplication doesn't seem
* feasible. The better fix is to move all users of this driver to
* driver model.
*/
baud_divisor = ns16550_calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
CONFIG_BAUDRATE);
serial_dout(&com_port->ier, CONFIG_SYS_NS16550_IER);
serial_dout(&com_port->mcr, UART_MCRVAL);
serial_dout(&com_port->fcr, UART_FCR_DEFVAL);
serial_dout(&com_port->lcr, UART_LCR_BKSE | UART_LCRVAL);
serial_dout(&com_port->dll, baud_divisor & 0xff);
serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff);
serial_dout(&com_port->lcr, UART_LCRVAL);
}
static inline void _debug_uart_putc(int ch)
{
struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
while (!(serial_din(&com_port->lsr) & UART_LSR_THRE))
;
serial_dout(&com_port->thr, ch);
}
DEBUG_UART_FUNCS
#endif
#ifdef CONFIG_DEBUG_UART_OMAP
#include <debug_uart.h>
static inline void _debug_uart_init(void)
{
struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
int baud_divisor;
baud_divisor = ns16550_calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
CONFIG_BAUDRATE);
serial_dout(&com_port->ier, CONFIG_SYS_NS16550_IER);
serial_dout(&com_port->mdr1, 0x7);
serial_dout(&com_port->mcr, UART_MCRVAL);
serial_dout(&com_port->fcr, UART_FCR_DEFVAL);
serial_dout(&com_port->lcr, UART_LCR_BKSE | UART_LCRVAL);
serial_dout(&com_port->dll, baud_divisor & 0xff);
serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff);
serial_dout(&com_port->lcr, UART_LCRVAL);
serial_dout(&com_port->mdr1, 0x0);
}
static inline void _debug_uart_putc(int ch)
{
struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
while (!(serial_din(&com_port->lsr) & UART_LSR_THRE))
;
serial_dout(&com_port->thr, ch);
}
DEBUG_UART_FUNCS
#endif
#ifdef CONFIG_DM_SERIAL
static int ns16550_serial_putc(struct udevice *dev, const char ch)
{
struct NS16550 *const com_port = dev_get_priv(dev);
if (!(serial_in(&com_port->lsr) & UART_LSR_THRE))
return -EAGAIN;
serial_out(ch, &com_port->thr);
/*
* Call watchdog_reset() upon newline. This is done here in putc
* since the environment code uses a single puts() to print the complete
* environment upon "printenv". So we can't put this watchdog call
* in puts().
*/
if (ch == '\n')
WATCHDOG_RESET();
return 0;
}
static int ns16550_serial_pending(struct udevice *dev, bool input)
{
struct NS16550 *const com_port = dev_get_priv(dev);
if (input)
return serial_in(&com_port->lsr) & UART_LSR_DR ? 1 : 0;
else
return serial_in(&com_port->lsr) & UART_LSR_THRE ? 0 : 1;
}
static int ns16550_serial_getc(struct udevice *dev)
{
struct NS16550 *const com_port = dev_get_priv(dev);
if (!(serial_in(&com_port->lsr) & UART_LSR_DR))
return -EAGAIN;
return serial_in(&com_port->rbr);
}
static int ns16550_serial_setbrg(struct udevice *dev, int baudrate)
{
struct NS16550 *const com_port = dev_get_priv(dev);
struct ns16550_platdata *plat = com_port->plat;
int clock_divisor;
clock_divisor = ns16550_calc_divisor(com_port, plat->clock, baudrate);
NS16550_setbrg(com_port, clock_divisor);
return 0;
}
int ns16550_serial_probe(struct udevice *dev)
{
struct NS16550 *const com_port = dev_get_priv(dev);
com_port->plat = dev_get_platdata(dev);
NS16550_init(com_port, -1);
return 0;
}
#if CONFIG_IS_ENABLED(OF_CONTROL)
enum {
PORT_NS16550 = 0,
PORT_JZ4780,
};
#endif
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
int ns16550_serial_ofdata_to_platdata(struct udevice *dev)
{
struct ns16550_platdata *plat = dev->platdata;
const u32 port_type = dev_get_driver_data(dev);
fdt_addr_t addr;
struct clk clk;
int err;
/* try Processor Local Bus device first */
addr = dev_read_addr(dev);
#if defined(CONFIG_PCI) && defined(CONFIG_DM_PCI)
if (addr == FDT_ADDR_T_NONE) {
/* then try pci device */
struct fdt_pci_addr pci_addr;
u32 bar;
int ret;
/* we prefer to use a memory-mapped register */
ret = fdtdec_get_pci_addr(gd->fdt_blob, dev_of_offset(dev),
FDT_PCI_SPACE_MEM32, "reg",
&pci_addr);
if (ret) {
/* try if there is any i/o-mapped register */
ret = fdtdec_get_pci_addr(gd->fdt_blob,
dev_of_offset(dev),
FDT_PCI_SPACE_IO,
"reg", &pci_addr);
if (ret)
return ret;
}
ret = fdtdec_get_pci_bar32(dev, &pci_addr, &bar);
if (ret)
return ret;
addr = bar;
}
#endif
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
#ifdef CONFIG_SYS_NS16550_PORT_MAPPED
plat->base = addr;
#else
plat->base = (unsigned long)map_physmem(addr, 0, MAP_NOCACHE);
#endif
plat->reg_offset = dev_read_u32_default(dev, "reg-offset", 0);
plat->reg_shift = dev_read_u32_default(dev, "reg-shift", 0);
err = clk_get_by_index(dev, 0, &clk);
if (!err) {
err = clk_get_rate(&clk);
if (!IS_ERR_VALUE(err))
plat->clock = err;
} else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) {
debug("ns16550 failed to get clock\n");
return err;
}
if (!plat->clock)
plat->clock = dev_read_u32_default(dev, "clock-frequency",
CONFIG_SYS_NS16550_CLK);
if (!plat->clock) {
debug("ns16550 clock not defined\n");
return -EINVAL;
}
plat->fcr = UART_FCR_DEFVAL;
if (port_type == PORT_JZ4780)
plat->fcr |= UART_FCR_UME;
return 0;
}
#endif
const struct dm_serial_ops ns16550_serial_ops = {
.putc = ns16550_serial_putc,
.pending = ns16550_serial_pending,
.getc = ns16550_serial_getc,
.setbrg = ns16550_serial_setbrg,
};
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
/*
* Please consider existing compatible strings before adding a new
* one to keep this table compact. Or you may add a generic "ns16550"
* compatible string to your dts.
*/
static const struct udevice_id ns16550_serial_ids[] = {
{ .compatible = "ns16550", .data = PORT_NS16550 },
{ .compatible = "ns16550a", .data = PORT_NS16550 },
{ .compatible = "ingenic,jz4780-uart", .data = PORT_JZ4780 },
{ .compatible = "nvidia,tegra20-uart", .data = PORT_NS16550 },
{ .compatible = "snps,dw-apb-uart", .data = PORT_NS16550 },
{ .compatible = "ti,omap2-uart", .data = PORT_NS16550 },
{ .compatible = "ti,omap3-uart", .data = PORT_NS16550 },
{ .compatible = "ti,omap4-uart", .data = PORT_NS16550 },
{ .compatible = "ti,am3352-uart", .data = PORT_NS16550 },
{ .compatible = "ti,am4372-uart", .data = PORT_NS16550 },
{ .compatible = "ti,dra742-uart", .data = PORT_NS16550 },
{}
};
#endif /* OF_CONTROL && !OF_PLATDATA */
#if CONFIG_IS_ENABLED(SERIAL_PRESENT)
/* TODO(sjg@chromium.org): Integrate this into a macro like CONFIG_IS_ENABLED */
#if !defined(CONFIG_TPL_BUILD) || defined(CONFIG_TPL_DM_SERIAL)
U_BOOT_DRIVER(ns16550_serial) = {
.name = "ns16550_serial",
.id = UCLASS_SERIAL,
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
.of_match = ns16550_serial_ids,
.ofdata_to_platdata = ns16550_serial_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct ns16550_platdata),
#endif
.priv_auto_alloc_size = sizeof(struct NS16550),
.probe = ns16550_serial_probe,
.ops = &ns16550_serial_ops,
.flags = DM_FLAG_PRE_RELOC,
};
#endif
#endif /* SERIAL_PRESENT */
#endif /* CONFIG_DM_SERIAL */