u-boot/drivers/serial/ns16550.c
Wolfgang Wallner 720f9e1fdb serial: ns16550: Move PCI access from ofdata_to_platdata() to probe()
Currently the ofdata_to_platdata() method calls dev_read_addr_pci(),
which potentially accesses the parent PCI bus. If this happens before
the parent PCI bus is probed the resulting address will be wrong.

This behavior was triggered by commit 82de42fa14 ("dm: core:
Allocate parent data separate from probing parent").

According to a comment in drivers/pci/pci-uclass.c [1] accessing
the PCI parent bus in ofdata_to_platdata() is not allowed, and the
access should be moved to the probe() function.

Move the call to dev_read_addr_pci() and the related handling of the
'addr' value from the ofdata_to_platdata() to its own function,
which is then called from the probe() method.

While moving the code, the comment /* try Processor Local Bus device
first */ was dropped. It was initially added with commit 3db886a5bf
("serial: ns16550: Support ns16550 compatible pci uart devices") and
later made obsolete with commit 33c215af4b ("dm: pci: Add a function
to read a PCI BAR").

[1] Comment in drivers/pci/pci-uclass.c:
"A common cause of this problem is that this function is called in the
ofdata_to_platdata() method of @dev. Accessing the PCI bus in that
method is not allowed, since it has not yet been probed. To fix this,
move that access to the probe() method of @dev instead."

Fixes: 82de42fa14 ("dm: core: Allocate parent data separate from probing parent")
Signed-off-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com> # Tested on Intel Galileo
2020-03-05 18:25:10 +08:00

618 lines
16 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 <clock_legacy.h>
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <errno.h>
#include <ns16550.h>
#include <reset.h>
#include <serial.h>
#include <watchdog.h>
#include <linux/err.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 */
#if !CONFIG_IS_ENABLED(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_LITTLE_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_LITTLE_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
}
#if CONFIG_IS_ENABLED(DM_SERIAL)
#ifndef CONFIG_SYS_NS16550_CLK
#define CONFIG_SYS_NS16550_CLK 0
#endif
/*
* Use this #ifdef for now since many platforms don't define in(), out(),
* out_le32(), etc. but we don't have #defines to indicate this.
*
* TODO(sjg@chromium.org): Add CONFIG options to indicate what I/O is available
* on a platform
*/
#ifdef CONFIG_NS16550_DYNAMIC
static void serial_out_dynamic(struct ns16550_platdata *plat, u8 *addr,
int value)
{
if (plat->flags & NS16550_FLAG_IO) {
outb(value, addr);
} else if (plat->reg_width == 4) {
if (plat->flags & NS16550_FLAG_ENDIAN) {
if (plat->flags & NS16550_FLAG_BE)
out_be32(addr, value);
else
out_le32(addr, value);
} else {
writel(value, addr);
}
} else if (plat->flags & NS16550_FLAG_BE) {
writeb(value, addr + (1 << plat->reg_shift) - 1);
} else {
writeb(value, addr);
}
}
static int serial_in_dynamic(struct ns16550_platdata *plat, u8 *addr)
{
if (plat->flags & NS16550_FLAG_IO) {
return inb(addr);
} else if (plat->reg_width == 4) {
if (plat->flags & NS16550_FLAG_ENDIAN) {
if (plat->flags & NS16550_FLAG_BE)
return in_be32(addr);
else
return in_le32(addr);
} else {
return readl(addr);
}
} else if (plat->flags & NS16550_FLAG_BE) {
return readb(addr + (1 << plat->reg_shift) - 1);
} else {
return readb(addr);
}
}
#else
static inline void serial_out_dynamic(struct ns16550_platdata *plat, u8 *addr,
int value)
{
}
static inline int serial_in_dynamic(struct ns16550_platdata *plat, u8 *addr)
{
return 0;
}
#endif /* CONFIG_NS16550_DYNAMIC */
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 + plat->reg_offset;
if (IS_ENABLED(CONFIG_NS16550_DYNAMIC))
serial_out_dynamic(plat, addr, value);
else
serial_out_shift(addr, 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 + plat->reg_offset;
if (IS_ENABLED(CONFIG_NS16550_DYNAMIC))
return serial_in_dynamic(plat, addr);
else
return serial_in_shift(addr, 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)
{
/* to keep serial format, read lcr before writing BKSE */
int lcr_val = serial_in(&com_port->lcr) & ~UART_LCR_BKSE;
serial_out(UART_LCR_BKSE | lcr_val, &com_port->lcr);
serial_out(baud_divisor & 0xff, &com_port->dll);
serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm);
serial_out(lcr_val, &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);
else {
// Re-use old baud rate divisor to flush transmit reg.
const int dll = serial_in(&com_port->dll);
const int dlm = serial_in(&com_port->dlm);
const int divisor = dll | (dlm << 8);
NS16550_setbrg(com_port, 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) || defined(CONFIG_OMAP_SERIAL)
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);
/* initialize serial config to 8N1 before writing baudrate */
serial_out(UART_LCRVAL, &com_port->lcr);
if (baud_divisor != -1)
NS16550_setbrg(com_port, baud_divisor);
#if defined(CONFIG_ARCH_OMAP2PLUS) || defined(CONFIG_SOC_DA8XX) || \
defined(CONFIG_OMAP_SERIAL)
/* /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 int NS16550_read_baud_divisor(struct NS16550 *com_port)
{
int ret;
serial_dout(&com_port->lcr, UART_LCR_BKSE | UART_LCRVAL);
ret = serial_din(&com_port->dll) & 0xff;
ret |= (serial_din(&com_port->dlm) & 0xff) << 8;
serial_dout(&com_port->lcr, UART_LCRVAL);
return ret;
}
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)) {
#ifdef CONFIG_DEBUG_UART_NS16550_CHECK_ENABLED
if (!NS16550_read_baud_divisor(com_port))
return;
#endif
}
serial_dout(&com_port->thr, ch);
}
DEBUG_UART_FUNCS
#endif
#if CONFIG_IS_ENABLED(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;
}
static int ns16550_serial_setconfig(struct udevice *dev, uint serial_config)
{
struct NS16550 *const com_port = dev_get_priv(dev);
int lcr_val = UART_LCR_WLS_8;
uint parity = SERIAL_GET_PARITY(serial_config);
uint bits = SERIAL_GET_BITS(serial_config);
uint stop = SERIAL_GET_STOP(serial_config);
/*
* only parity config is implemented, check if other serial settings
* are the default one.
*/
if (bits != SERIAL_8_BITS || stop != SERIAL_ONE_STOP)
return -ENOTSUPP; /* not supported in driver*/
switch (parity) {
case SERIAL_PAR_NONE:
/* no bits to add */
break;
case SERIAL_PAR_ODD:
lcr_val |= UART_LCR_PEN;
break;
case SERIAL_PAR_EVEN:
lcr_val |= UART_LCR_PEN | UART_LCR_EPS;
break;
default:
return -ENOTSUPP; /* not supported in driver*/
}
serial_out(lcr_val, &com_port->lcr);
return 0;
}
static int ns16550_serial_getinfo(struct udevice *dev,
struct serial_device_info *info)
{
struct NS16550 *const com_port = dev_get_priv(dev);
struct ns16550_platdata *plat = com_port->plat;
info->type = SERIAL_CHIP_16550_COMPATIBLE;
#ifdef CONFIG_SYS_NS16550_PORT_MAPPED
info->addr_space = SERIAL_ADDRESS_SPACE_IO;
#else
info->addr_space = SERIAL_ADDRESS_SPACE_MEMORY;
#endif
info->addr = plat->base;
info->reg_width = plat->reg_width;
info->reg_shift = plat->reg_shift;
info->reg_offset = plat->reg_offset;
return 0;
}
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
static int ns1655_serial_set_base_addr(struct udevice *dev)
{
fdt_addr_t addr;
struct ns16550_platdata *plat;
plat = dev_get_platdata(dev);
addr = dev_read_addr_pci(dev);
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
return 0;
}
#endif
int ns16550_serial_probe(struct udevice *dev)
{
struct NS16550 *const com_port = dev_get_priv(dev);
struct reset_ctl_bulk reset_bulk;
int ret;
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
ret = ns1655_serial_set_base_addr(dev);
if (ret)
return ret;
#endif
ret = reset_get_bulk(dev, &reset_bulk);
if (!ret)
reset_deassert_bulk(&reset_bulk);
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);
struct clk clk;
int err;
plat->reg_offset = dev_read_u32_default(dev, "reg-offset", 0);
plat->reg_shift = dev_read_u32_default(dev, "reg-shift", 0);
plat->reg_width = dev_read_u32_default(dev, "reg-io-width", 1);
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,
.setconfig = ns16550_serial_setconfig,
.getinfo = ns16550_serial_getinfo,
};
#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 },
{}
};
#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,
#if !CONFIG_IS_ENABLED(OF_CONTROL)
.flags = DM_FLAG_PRE_RELOC,
#endif
};
#endif
#endif /* SERIAL_PRESENT */
#endif /* CONFIG_DM_SERIAL */