It is based on linux/drivers/tty/serial/bcm63xx_uart.c
Signed-off-by: Álvaro Fernández Rojas noltari@gmail.com --- v4: Add more missing register configurations based on CFE. v3: Several improvements: - Add missing register configurations based on CFE. - Replace tabs with whitespaces. - Cosmetic fixes. v2: Introduce changes suggested by Daniel Schwierzeck: - Remove unneeded defines. - Fix incorrect multi-line comment.
drivers/serial/Kconfig | 14 ++ drivers/serial/Makefile | 1 + drivers/serial/serial_bcm6345.c | 311 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 326 insertions(+) create mode 100644 drivers/serial/serial_bcm6345.c
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index c0ec2ec..ca776d8 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -134,6 +134,14 @@ config DEBUG_UART_ATMEL will need to provide parameters to make this work. The driver will be available until the real driver-model serial is running.
+config DEBUG_UART_BCM6345 + bool "BCM6345 UART" + depends on BCM6345_SERIAL + help + Select this to enable a debug UART on BCM6345 SoCs. You + will need to provide parameters to make this work. The driver will + be available until the real driver model serial is running. + config DEBUG_UART_NS16550 bool "ns16550" help @@ -339,6 +347,12 @@ config ATMEL_USART configured in the device tree, and input clock frequency can be got from the clk node.
+config BCM6345_SERIAL + bool "Support for BCM6345 UART" + depends on DM_SERIAL + help + Select this to enable UART on BCM6345 SoCs. + config FSL_LPUART bool "Freescale LPUART support" help diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index 4382cf9..dca31b2 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_ALTERA_JTAG_UART) += altera_jtag_uart.o obj-$(CONFIG_AR933X_UART) += serial_ar933x.o obj-$(CONFIG_ARM_DCC) += arm_dcc.o obj-$(CONFIG_ATMEL_USART) += atmel_usart.o +obj-$(CONFIG_BCM6345_SERIAL) += serial_bcm6345.o obj-$(CONFIG_EFI_APP) += serial_efi.o obj-$(CONFIG_LPC32XX_HSUART) += lpc32xx_hsuart.o obj-$(CONFIG_MCFUART) += mcfuart.o diff --git a/drivers/serial/serial_bcm6345.c b/drivers/serial/serial_bcm6345.c new file mode 100644 index 0000000..e4d3497 --- /dev/null +++ b/drivers/serial/serial_bcm6345.c @@ -0,0 +1,311 @@ +/* + * Copyright (C) 2017 Álvaro Fernández Rojas noltari@gmail.com + * + * Derived from linux/drivers/tty/serial/bcm63xx_uart.c: + * Copyright (C) 2008 Maxime Bizon mbizon@freebox.fr + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <clk.h> +#include <debug_uart.h> +#include <errno.h> +#include <serial.h> +#include <asm/io.h> +#include <asm/types.h> +#include <dm/device.h> + +/* UART Control register */ +#define UART_CTL_REG 0x0 +#define UART_CTL_RXTIMEOUT_MASK 0x1f +#define UART_CTL_RSTRXFIFO_SHIFT 6 +#define UART_CTL_RSTRXFIFO_MASK (1 << UART_CTL_RSTRXFIFO_SHIFT) +#define UART_CTL_RSTTXFIFO_SHIFT 7 +#define UART_CTL_RSTTXFIFO_MASK (1 << UART_CTL_RSTTXFIFO_SHIFT) +#define UART_CTL_STOPBITS_SHIFT 8 +#define UART_CTL_STOPBITS_MASK (0xf << UART_CTL_STOPBITS_SHIFT) +#define UART_CTL_STOPBITS_1 (0x7 << UART_CTL_STOPBITS_SHIFT) +#define UART_CTL_BITSPERSYM_SHIFT 12 +#define UART_CTL_BITSPERSYM_MASK (0x3 << UART_CTL_BITSPERSYM_SHIFT) +#define UART_CTL_XMITBRK_SHIFT 14 +#define UART_CTL_XMITBRK_MASK (1 << UART_CTL_XMITBRK_SHIFT) +#define UART_CTL_RSVD_SHIFT 15 +#define UART_CTL_RSVD_MASK (1 << UART_CTL_RSVD_SHIFT) +#define UART_CTL_RXPAREVEN_SHIFT 16 +#define UART_CTL_RXPAREVEN_MASK (1 << UART_CTL_RXPAREVEN_SHIFT) +#define UART_CTL_RXPAREN_SHIFT 17 +#define UART_CTL_RXPAREN_MASK (1 << UART_CTL_RXPAREN_SHIFT) +#define UART_CTL_TXPAREVEN_SHIFT 18 +#define UART_CTL_TXPAREVEN_MASK (1 << UART_CTL_TXPAREVEN_SHIFT) +#define UART_CTL_TXPAREN_SHIFT 19 +#define UART_CTL_TXPAREN_MASK (1 << UART_CTL_TXPAREN_SHIFT) +#define UART_CTL_LOOPBACK_SHIFT 20 +#define UART_CTL_LOOPBACK_MASK (1 << UART_CTL_LOOPBACK_SHIFT) +#define UART_CTL_RXEN_SHIFT 21 +#define UART_CTL_RXEN_MASK (1 << UART_CTL_RXEN_SHIFT) +#define UART_CTL_TXEN_SHIFT 22 +#define UART_CTL_TXEN_MASK (1 << UART_CTL_TXEN_SHIFT) +#define UART_CTL_BRGEN_SHIFT 23 +#define UART_CTL_BRGEN_MASK (1 << UART_CTL_BRGEN_SHIFT) + +/* UART Baudword register */ +#define UART_BAUD_REG 0x4 + +/* UART FIFO Config register */ +#define UART_FIFO_CFG_REG 0x8 +#define UART_FIFO_CFG_RX_SHIFT 8 +#define UART_FIFO_CFG_RX_MASK (0xf << UART_FIFO_CFG_RX_SHIFT) +#define UART_FIFO_CFG_TX_SHIFT 12 +#define UART_FIFO_CFG_TX_MASK (0xf << UART_FIFO_CFG_TX_SHIFT) + +/* UART Interrupt register */ +#define UART_IR_REG 0x10 +#define UART_IR_STAT(x) (1 << (x)) +#define UART_IR_TXEMPTY 5 +#define UART_IR_RXOVER 7 +#define UART_IR_RXNOTEMPTY 11 + +/* UART FIFO register */ +#define UART_FIFO_REG 0x14 +#define UART_FIFO_VALID_MASK 0xff +#define UART_FIFO_FRAMEERR_SHIFT 8 +#define UART_FIFO_FRAMEERR_MASK (1 << UART_FIFO_FRAMEERR_SHIFT) +#define UART_FIFO_PARERR_SHIFT 9 +#define UART_FIFO_PARERR_MASK (1 << UART_FIFO_PARERR_SHIFT) +#define UART_FIFO_BRKDET_SHIFT 10 +#define UART_FIFO_BRKDET_MASK (1 << UART_FIFO_BRKDET_SHIFT) +#define UART_FIFO_ANYERR_MASK (UART_FIFO_FRAMEERR_MASK | \ + UART_FIFO_PARERR_MASK | \ + UART_FIFO_BRKDET_MASK) + +struct bcm6345_serial_priv { + void __iomem *base; + ulong uartclk; +}; + +/* + * enable rx & tx operation on uart + */ +static void bcm6345_serial_enable(void __iomem *base) +{ + u32 val; + + val = __raw_readl(base + UART_CTL_REG); + val |= (UART_CTL_BRGEN_MASK | UART_CTL_TXEN_MASK | UART_CTL_RXEN_MASK); + __raw_writel(val, base + UART_CTL_REG); +} + +/* + * disable rx & tx operation on uart + */ +static void bcm6345_serial_disable(void __iomem *base) +{ + u32 val; + + val = __raw_readl(base + UART_CTL_REG); + val &= ~(UART_CTL_BRGEN_MASK | UART_CTL_TXEN_MASK | + UART_CTL_RXEN_MASK); + __raw_writel(val, base + UART_CTL_REG); +} + +/* + * clear all unread data in rx fifo and unsent data in tx fifo + */ +static void bcm6345_serial_flush(void __iomem *base) +{ + u32 val; + + /* empty rx and tx fifo */ + val = __raw_readl(base + UART_CTL_REG); + val |= UART_CTL_RSTRXFIFO_MASK | UART_CTL_RSTTXFIFO_MASK; + __raw_writel(val, base + UART_CTL_REG); + + /* read any pending char to make sure all irq status are cleared */ + __raw_readl(base + UART_FIFO_REG); +} + +static int bcm6345_serial_init(void __iomem *base, ulong clk, u32 baudrate) +{ + u32 val; + + /* mask all irq and flush port */ + bcm6345_serial_disable(base); + bcm6345_serial_flush(base); + + val = __raw_readl(base + UART_CTL_REG); + /* set rx timeout */ + val &= ~UART_CTL_RXTIMEOUT_MASK; + val |= 0x5; + /* set stop bits */ + val &= ~UART_CTL_STOPBITS_MASK; + val |= UART_CTL_STOPBITS_1; + /* set bits per symbol */ + val &= ~UART_CTL_BITSPERSYM_MASK; + val |= (3 << UART_CTL_BITSPERSYM_SHIFT); + /* clear xmit break */ + val &= ~UART_CTL_XMITBRK_MASK; + /* clear reserved bit */ + val &= ~UART_CTL_RSVD_MASK; + /* disable parity */ + val |= UART_CTL_RXPAREVEN_MASK | UART_CTL_TXPAREVEN_MASK; + val &= ~(UART_CTL_RXPAREN_MASK | UART_CTL_TXPAREN_MASK); + /* disable loopback */ + val &= ~UART_CTL_LOOPBACK_MASK; + __raw_writel(val, base + UART_CTL_REG); + + val = __raw_readl(base + UART_FIFO_CFG_REG); + /* set rx fifo config */ + val &= ~UART_FIFO_CFG_RX_MASK; + val |= (4 << UART_FIFO_CFG_RX_SHIFT); + /* set tx fifo config */ + val &= ~UART_FIFO_CFG_TX_MASK; + val |= (4 << UART_FIFO_CFG_TX_SHIFT); + __raw_writel(val, base + UART_FIFO_CFG_REG); + + /* set baud rate */ + val = (clk / baudrate) / 16; + if (val & 0x1) + val = val; + else + val = val / 2 - 1; + __raw_writel(val, base + UART_BAUD_REG); + + /* clear interrupts */ + __raw_writel(0, base + UART_IR_REG); + + /* enable uart */ + bcm6345_serial_enable(base); + + return 0; +} + +static int bcm6345_serial_pending(struct udevice *dev, bool input) +{ + struct bcm6345_serial_priv *priv = dev_get_priv(dev); + u32 val = __raw_readl(priv->base + UART_IR_REG); + + if (input) + return (val & UART_IR_STAT(UART_IR_RXNOTEMPTY)) ? 1 : 0; + else + return (val & UART_IR_STAT(UART_IR_TXEMPTY)) ? 0 : 1; +} + +static int bcm6345_serial_setbrg(struct udevice *dev, int baudrate) +{ + struct bcm6345_serial_priv *priv = dev_get_priv(dev); + + return bcm6345_serial_init(priv->base, priv->uartclk, baudrate); +} + +static int bcm6345_serial_putc(struct udevice *dev, const char ch) +{ + struct bcm6345_serial_priv *priv = dev_get_priv(dev); + u32 val; + + val = __raw_readl(priv->base + UART_IR_REG); + if (!(val & UART_IR_STAT(UART_IR_TXEMPTY))) + return -EAGAIN; + + __raw_writel(ch, priv->base + UART_FIFO_REG); + + return 0; +} + +static int bcm6345_serial_getc(struct udevice *dev) +{ + struct bcm6345_serial_priv *priv = dev_get_priv(dev); + u32 val; + + val = __raw_readl(priv->base + UART_IR_REG); + if (val & UART_IR_STAT(UART_IR_RXOVER)) { + /* fifo reset is required to clear interrupt */ + val = __raw_readl(priv->base + UART_CTL_REG); + val |= UART_CTL_RSTRXFIFO_MASK; + __raw_writel(val, priv->base + UART_CTL_REG); + } + if (!(val & UART_IR_STAT(UART_IR_RXNOTEMPTY))) + return -EAGAIN; + + val = __raw_readl(priv->base + UART_FIFO_REG); + if (val & UART_FIFO_ANYERR_MASK) + return -EAGAIN; + + return (val & UART_FIFO_VALID_MASK); +} + +static int bcm6345_serial_probe(struct udevice *dev) +{ + struct bcm6345_serial_priv *priv = dev_get_priv(dev); + struct clk clk; + fdt_addr_t addr; + fdt_size_t size; + int ret; + + /* get address */ + addr = dev_get_addr_size_index(dev, 0, &size); + if (addr == FDT_ADDR_T_NONE) + return -EINVAL; + + priv->base = ioremap(addr, size); + + /* get clock rate */ + ret = clk_get_by_index(dev, 0, &clk); + if (ret < 0) + return ret; + priv->uartclk = clk_get_rate(&clk) / 2; + clk_free(&clk); + + /* initialize serial */ + return bcm6345_serial_init(priv->base, priv->uartclk, CONFIG_BAUDRATE); +} + +static const struct dm_serial_ops bcm6345_serial_ops = { + .putc = bcm6345_serial_putc, + .pending = bcm6345_serial_pending, + .getc = bcm6345_serial_getc, + .setbrg = bcm6345_serial_setbrg, +}; + +static const struct udevice_id bcm6345_serial_ids[] = { + { .compatible = "brcm,bcm6345-uart" }, + { /* sentinel */ } +}; + +U_BOOT_DRIVER(bcm6345_serial) = { + .name = "bcm6345-uart", + .id = UCLASS_SERIAL, + .of_match = bcm6345_serial_ids, + .probe = bcm6345_serial_probe, + .priv_auto_alloc_size = sizeof(struct bcm6345_serial_priv), + .ops = &bcm6345_serial_ops, + .flags = DM_FLAG_PRE_RELOC, +}; + +#ifdef CONFIG_DEBUG_UART_BCM6345 +static inline void _debug_uart_init(void) +{ + void __iomem *base = (void __iomem *)CONFIG_DEBUG_UART_BASE; + + bcm6345_serial_init(base, CONFIG_DEBUG_UART_CLOCK, CONFIG_BAUDRATE); +} + +static inline void wait_xfered(void __iomem *base) +{ + do { + u32 val = __raw_readl(base + UART_IR_REG); + if (val & UART_IR_STAT(UART_IR_TXEMPTY)) + break; + } while (1); +} + +static inline void _debug_uart_putc(int ch) +{ + void __iomem *base = (void __iomem *)CONFIG_DEBUG_UART_BASE; + + wait_xfered(base); + __raw_writel(ch, base + UART_FIFO_REG); + wait_xfered(base); +} + +DEBUG_UART_FUNCS +#endif