Message ID | 5672F0FC.6080609@microchip.com |
---|---|
State | Superseded |
Delegated to: | Daniel Schwierzeck |
Headers | show |
On Thursday, December 17, 2015 at 06:29:32 PM, Purna Chandra Mandal wrote: Hi! Minor nits below. btw do we expect MIPS to become maintained in U-Boot? That's nice :) [...] > diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile > index dd87147..57cd38b 100644 > --- a/drivers/serial/Makefile > +++ b/drivers/serial/Makefile > @@ -41,6 +41,7 @@ obj-$(CONFIG_MXS_AUART) += mxs_auart.o > obj-$(CONFIG_ARC_SERIAL) += serial_arc.o > obj-$(CONFIG_UNIPHIER_SERIAL) += serial_uniphier.o > obj-$(CONFIG_STM32_SERIAL) += serial_stm32.o > +obj-$(CONFIG_PIC32_SERIAL) += serial_pic32.o > > ifndef CONFIG_SPL_BUILD > obj-$(CONFIG_USB_TTY) += usbtty.o > diff --git a/drivers/serial/serial_pic32.c b/drivers/serial/serial_pic32.c > new file mode 100644 > index 0000000..01c62e7 > --- /dev/null > +++ b/drivers/serial/serial_pic32.c > @@ -0,0 +1,220 @@ > +/* > + * (c) 2015 Paul Thacker <paul.thacker@microchip.com> > + * > + * SPDX-License-Identifier: GPL-2.0+ > + * > + */ > +#include <common.h> > +#include <dm.h> > +#include <clk.h> > +#include <errno.h> > +#include <config.h> > +#include <serial.h> > +#include <linux/bitops.h> > +#include <common.h> > +#include <asm/io.h> > +#include <asm/arch-pic32/pic32.h> > +#include <asm/arch-pic32/clock.h> > + > +DECLARE_GLOBAL_DATA_PTR; > + > +#define UART_ENABLE BIT(15) > +#define UART_ENABLE_RX BIT(12) > +#define UART_ENABLE_TX BIT(10) > +#define UART_RX_DATA_AVAIL BIT(0) > +#define UART_RX_OERR BIT(1) > +#define UART_TX_FULL BIT(9) > + > +/* UART Control */ > +#define U_BASE(x) (x) > +#define U_MODE(x) U_BASE(x) > +#define U_MODECLR(x) (U_MODE(x) + _CLR_OFFSET) > +#define U_MODESET(x) (U_MODE(x) + _SET_OFFSET) > +#define U_STA(x) (U_BASE(x) + 0x10) > +#define U_STACLR(x) (U_STA(x) + _CLR_OFFSET) > +#define U_STASET(x) (U_STA(x) + _SET_OFFSET) > +#define U_TXREG(x) (U_BASE(x) + 0x20) > +#define U_RXREG(x) (U_BASE(x) + 0x30) > +#define U_BRG(x) (U_BASE(x) + 0x40) Why don't you just use uart_priv->regs + PIC32_REGISTER_OFFSET in the code? The U_BASE is redundant and so is UMODE. > +struct pic32_uart_priv { > + void __iomem *regs; > + ulong uartclk; > +}; > + > +static void pic32_serial_setbrg(void __iomem *regs, ulong uart_clk, u32 > baud) +{ > + writel(0, U_BRG(regs)); > + writel((uart_clk / baud / 16) - 1, U_BRG(regs)); > + udelay(100); > +} > + > +/* > + * Initialize the serial port with the given baudrate. > + * The settings are always 8 data bits, no parity, 1 stop bit, no start > bits. + */ > +static int pic32_serial_init(void __iomem *regs, ulong clk, u32 baudrate) > +{ > + /* disable and clear mode */ > + writel(0, U_MODE(regs)); > + writel(0, U_STA(regs)); > + > + /* set baud rate generator */ > + pic32_serial_setbrg(regs, clk, baudrate); > + > + /* enable the UART for TX and RX */ > + writel(UART_ENABLE_TX | UART_ENABLE_RX, U_STASET(regs)); > + > + /* enable the UART */ > + writel(UART_ENABLE, U_MODESET(regs)); > + return 0; > +} > + > +/* Output a single byte to the serial port */ > +static void pic32_serial_putc(void __iomem *regs, const char c) > +{ > + /* if \n, then add a \r */ > + if (c == '\n') > + pic32_serial_putc(regs, '\r'); > + > + /* Wait for Tx FIFO not full */ > + while (readl(U_STA(regs)) & UART_TX_FULL) > + ; > + > + /* stuff the tx buffer with the character */ > + writel(c, U_TXREG(regs)); > +} > + > +/* Test whether a character is in the RX buffer */ > +static int pic32_serial_tstc(void __iomem *regs) > +{ > + /* check if rcv buf overrun error has occurred */ > + if (readl(U_STA(regs)) & UART_RX_OERR) { > + readl(U_RXREG(regs)); > + > + /* clear OERR to keep receiving */ > + writel(UART_RX_OERR, U_STACLR(regs)); > + } > + > + if (readl(U_STA(regs)) & UART_RX_DATA_AVAIL) > + return 1; /* yes, there is data in rcv buffer */ > + else > + return 0; /* no data in rcv buffer */ return readl() & UART_RX_DATA_AVAIL; is sufficient here. > +} > + > +/* > + * Read a single byte from the rx buffer. > + * Blocking: waits until a character is received, then returns. > + * Return the character read directly from the UART's receive register. > + * > + */ > +static int pic32_serial_getc(void __iomem *regs) > +{ > + /* wait here until data is available */ > + while (!pic32_serial_tstc(regs)) > + ; > + > + /* read the character from the rcv buffer */ > + return readl(U_RXREG(regs)); return readl() & 0xff, since the return value is a signed integer. > +} [...] > +U_BOOT_DRIVER(pic32_serial) = { > + .name = "pic32-uart", > + .id = UCLASS_SERIAL, > + .of_match = pic32_uart_ids, > + .probe = pic32_uart_probe, > + .ops = &pic32_uart_ops, > + .flags = DM_FLAG_PRE_RELOC, > + .ofdata_to_platdata = pic32_uart_ofdata_to_platdata, > + .platdata_auto_alloc_size = sizeof(struct pic32_uart_priv), Is there some problem with tab/space conversion going on in here? > +}; > + [...]
On 12/17/2015 11:22 PM, Marek Vasut wrote: > On Thursday, December 17, 2015 at 06:29:32 PM, Purna Chandra Mandal wrote: > > Hi! > > Minor nits below. > > btw do we expect MIPS to become maintained in U-Boot? That's nice :) > > [...] > >> diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile >> index dd87147..57cd38b 100644 >> --- a/drivers/serial/Makefile >> +++ b/drivers/serial/Makefile >> @@ -41,6 +41,7 @@ obj-$(CONFIG_MXS_AUART) += mxs_auart.o >> obj-$(CONFIG_ARC_SERIAL) += serial_arc.o >> obj-$(CONFIG_UNIPHIER_SERIAL) += serial_uniphier.o >> obj-$(CONFIG_STM32_SERIAL) += serial_stm32.o >> +obj-$(CONFIG_PIC32_SERIAL) += serial_pic32.o >> >> ifndef CONFIG_SPL_BUILD >> obj-$(CONFIG_USB_TTY) += usbtty.o >> diff --git a/drivers/serial/serial_pic32.c b/drivers/serial/serial_pic32.c >> new file mode 100644 >> index 0000000..01c62e7 >> --- /dev/null >> +++ b/drivers/serial/serial_pic32.c >> @@ -0,0 +1,220 @@ >> +/* >> + * (c) 2015 Paul Thacker <paul.thacker@microchip.com> >> + * >> + * SPDX-License-Identifier: GPL-2.0+ >> + * >> + */ >> +#include <common.h> >> +#include <dm.h> >> +#include <clk.h> >> +#include <errno.h> >> +#include <config.h> >> +#include <serial.h> >> +#include <linux/bitops.h> >> +#include <common.h> >> +#include <asm/io.h> >> +#include <asm/arch-pic32/pic32.h> >> +#include <asm/arch-pic32/clock.h> >> + >> +DECLARE_GLOBAL_DATA_PTR; >> + >> +#define UART_ENABLE BIT(15) >> +#define UART_ENABLE_RX BIT(12) >> +#define UART_ENABLE_TX BIT(10) >> +#define UART_RX_DATA_AVAIL BIT(0) >> +#define UART_RX_OERR BIT(1) >> +#define UART_TX_FULL BIT(9) >> + >> +/* UART Control */ >> +#define U_BASE(x) (x) >> +#define U_MODE(x) U_BASE(x) >> +#define U_MODECLR(x) (U_MODE(x) + _CLR_OFFSET) >> +#define U_MODESET(x) (U_MODE(x) + _SET_OFFSET) >> +#define U_STA(x) (U_BASE(x) + 0x10) >> +#define U_STACLR(x) (U_STA(x) + _CLR_OFFSET) >> +#define U_STASET(x) (U_STA(x) + _SET_OFFSET) >> +#define U_TXREG(x) (U_BASE(x) + 0x20) >> +#define U_RXREG(x) (U_BASE(x) + 0x30) >> +#define U_BRG(x) (U_BASE(x) + 0x40) > Why don't you just use uart_priv->regs + PIC32_REGISTER_OFFSET in the code? > The U_BASE is redundant and so is UMODE. ack. Will update. >> +struct pic32_uart_priv { >> + void __iomem *regs; >> + ulong uartclk; >> +}; >> + >> +static void pic32_serial_setbrg(void __iomem *regs, ulong uart_clk, u32 >> baud) +{ >> + writel(0, U_BRG(regs)); >> + writel((uart_clk / baud / 16) - 1, U_BRG(regs)); >> + udelay(100); >> +} >> + >> +/* >> + * Initialize the serial port with the given baudrate. >> + * The settings are always 8 data bits, no parity, 1 stop bit, no start >> bits. + */ >> +static int pic32_serial_init(void __iomem *regs, ulong clk, u32 baudrate) >> +{ >> + /* disable and clear mode */ >> + writel(0, U_MODE(regs)); >> + writel(0, U_STA(regs)); >> + >> + /* set baud rate generator */ >> + pic32_serial_setbrg(regs, clk, baudrate); >> + >> + /* enable the UART for TX and RX */ >> + writel(UART_ENABLE_TX | UART_ENABLE_RX, U_STASET(regs)); >> + >> + /* enable the UART */ >> + writel(UART_ENABLE, U_MODESET(regs)); >> + return 0; >> +} >> + >> +/* Output a single byte to the serial port */ >> +static void pic32_serial_putc(void __iomem *regs, const char c) >> +{ >> + /* if \n, then add a \r */ >> + if (c == '\n') >> + pic32_serial_putc(regs, '\r'); >> + >> + /* Wait for Tx FIFO not full */ >> + while (readl(U_STA(regs)) & UART_TX_FULL) >> + ; >> + >> + /* stuff the tx buffer with the character */ >> + writel(c, U_TXREG(regs)); >> +} >> + >> +/* Test whether a character is in the RX buffer */ >> +static int pic32_serial_tstc(void __iomem *regs) >> +{ >> + /* check if rcv buf overrun error has occurred */ >> + if (readl(U_STA(regs)) & UART_RX_OERR) { >> + readl(U_RXREG(regs)); >> + >> + /* clear OERR to keep receiving */ >> + writel(UART_RX_OERR, U_STACLR(regs)); >> + } >> + >> + if (readl(U_STA(regs)) & UART_RX_DATA_AVAIL) >> + return 1; /* yes, there is data in rcv buffer */ >> + else >> + return 0; /* no data in rcv buffer */ > return readl() & UART_RX_DATA_AVAIL; is sufficient here. ack. >> +} >> + >> +/* >> + * Read a single byte from the rx buffer. >> + * Blocking: waits until a character is received, then returns. >> + * Return the character read directly from the UART's receive register. >> + * >> + */ >> +static int pic32_serial_getc(void __iomem *regs) >> +{ >> + /* wait here until data is available */ >> + while (!pic32_serial_tstc(regs)) >> + ; >> + >> + /* read the character from the rcv buffer */ >> + return readl(U_RXREG(regs)); > return readl() & 0xff, since the return value is a signed integer. ack. >> +} > [...] > >> +U_BOOT_DRIVER(pic32_serial) = { >> + .name = "pic32-uart", >> + .id = UCLASS_SERIAL, >> + .of_match = pic32_uart_ids, >> + .probe = pic32_uart_probe, >> + .ops = &pic32_uart_ops, >> + .flags = DM_FLAG_PRE_RELOC, >> + .ofdata_to_platdata = pic32_uart_ofdata_to_platdata, >> + .platdata_auto_alloc_size = sizeof(struct pic32_uart_priv), > Is there some problem with tab/space conversion going on in here? ack. will fix. >> +}; >> + > [...]
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 1fc287e..9763ea1 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -107,6 +107,14 @@ config DEBUG_UART_APBUART 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_PIC32 + bool "Microchip PIC32" + help + Select this to enable a debug UART using the serial_pic32 driver. You + will need to provide parameters to make this work. The driver will + be available until the real driver model serial is running. + + endchoice config DEBUG_UART_BASE @@ -223,4 +231,9 @@ config UNIPHIER_SERIAL If you have a UniPhier based board and want to use the on-chip serial ports, say Y to this option. If unsure, say N. +config PIC32_SERIAL + bool "Support for Microchip PIC32 on-chip UART" + help + Support for the UART found on Microchip PIC32 SoC's. + endmenu diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index dd87147..57cd38b 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -41,6 +41,7 @@ obj-$(CONFIG_MXS_AUART) += mxs_auart.o obj-$(CONFIG_ARC_SERIAL) += serial_arc.o obj-$(CONFIG_UNIPHIER_SERIAL) += serial_uniphier.o obj-$(CONFIG_STM32_SERIAL) += serial_stm32.o +obj-$(CONFIG_PIC32_SERIAL) += serial_pic32.o ifndef CONFIG_SPL_BUILD obj-$(CONFIG_USB_TTY) += usbtty.o diff --git a/drivers/serial/serial_pic32.c b/drivers/serial/serial_pic32.c new file mode 100644 index 0000000..01c62e7 --- /dev/null +++ b/drivers/serial/serial_pic32.c @@ -0,0 +1,220 @@ +/* + * (c) 2015 Paul Thacker <paul.thacker@microchip.com> + * + * SPDX-License-Identifier: GPL-2.0+ + * + */ +#include <common.h> +#include <dm.h> +#include <clk.h> +#include <errno.h> +#include <config.h> +#include <serial.h> +#include <linux/bitops.h> +#include <common.h> +#include <asm/io.h> +#include <asm/arch-pic32/pic32.h> +#include <asm/arch-pic32/clock.h> + +DECLARE_GLOBAL_DATA_PTR; + +#define UART_ENABLE BIT(15) +#define UART_ENABLE_RX BIT(12) +#define UART_ENABLE_TX BIT(10) +#define UART_RX_DATA_AVAIL BIT(0) +#define UART_RX_OERR BIT(1) +#define UART_TX_FULL BIT(9) + +/* UART Control */ +#define U_BASE(x) (x) +#define U_MODE(x) U_BASE(x) +#define U_MODECLR(x) (U_MODE(x) + _CLR_OFFSET) +#define U_MODESET(x) (U_MODE(x) + _SET_OFFSET) +#define U_STA(x) (U_BASE(x) + 0x10) +#define U_STACLR(x) (U_STA(x) + _CLR_OFFSET) +#define U_STASET(x) (U_STA(x) + _SET_OFFSET) +#define U_TXREG(x) (U_BASE(x) + 0x20) +#define U_RXREG(x) (U_BASE(x) + 0x30) +#define U_BRG(x) (U_BASE(x) + 0x40) + +struct pic32_uart_priv { + void __iomem *regs; + ulong uartclk; +}; + +static void pic32_serial_setbrg(void __iomem *regs, ulong uart_clk, u32 baud) +{ + writel(0, U_BRG(regs)); + writel((uart_clk / baud / 16) - 1, U_BRG(regs)); + udelay(100); +} + +/* + * Initialize the serial port with the given baudrate. + * The settings are always 8 data bits, no parity, 1 stop bit, no start bits. + */ +static int pic32_serial_init(void __iomem *regs, ulong clk, u32 baudrate) +{ + /* disable and clear mode */ + writel(0, U_MODE(regs)); + writel(0, U_STA(regs)); + + /* set baud rate generator */ + pic32_serial_setbrg(regs, clk, baudrate); + + /* enable the UART for TX and RX */ + writel(UART_ENABLE_TX | UART_ENABLE_RX, U_STASET(regs)); + + /* enable the UART */ + writel(UART_ENABLE, U_MODESET(regs)); + return 0; +} + +/* Output a single byte to the serial port */ +static void pic32_serial_putc(void __iomem *regs, const char c) +{ + /* if \n, then add a \r */ + if (c == '\n') + pic32_serial_putc(regs, '\r'); + + /* Wait for Tx FIFO not full */ + while (readl(U_STA(regs)) & UART_TX_FULL) + ; + + /* stuff the tx buffer with the character */ + writel(c, U_TXREG(regs)); +} + +/* Test whether a character is in the RX buffer */ +static int pic32_serial_tstc(void __iomem *regs) +{ + /* check if rcv buf overrun error has occurred */ + if (readl(U_STA(regs)) & UART_RX_OERR) { + readl(U_RXREG(regs)); + + /* clear OERR to keep receiving */ + writel(UART_RX_OERR, U_STACLR(regs)); + } + + if (readl(U_STA(regs)) & UART_RX_DATA_AVAIL) + return 1; /* yes, there is data in rcv buffer */ + else + return 0; /* no data in rcv buffer */ +} + +/* + * Read a single byte from the rx buffer. + * Blocking: waits until a character is received, then returns. + * Return the character read directly from the UART's receive register. + * + */ +static int pic32_serial_getc(void __iomem *regs) +{ + /* wait here until data is available */ + while (!pic32_serial_tstc(regs)) + ; + + /* read the character from the rcv buffer */ + return readl(U_RXREG(regs)); +} + +static int pic32_uart_pending(struct udevice *dev, bool input) +{ + struct pic32_uart_priv *priv = dev_get_platdata(dev); + + return pic32_serial_tstc(priv->regs); +} + +static int pic32_uart_setbrg(struct udevice *dev, int baudrate) +{ + struct pic32_uart_priv *priv = dev_get_platdata(dev); + + pic32_serial_init(priv->regs, priv->uartclk, baudrate); + return 0; +} + +static int pic32_uart_putc(struct udevice *dev, const char ch) +{ + struct pic32_uart_priv *priv = dev_get_platdata(dev); + + pic32_serial_putc(priv->regs, ch); + return 0; +} + +static int pic32_uart_getc(struct udevice *dev) +{ + struct pic32_uart_priv *priv = dev_get_platdata(dev); + + return pic32_serial_getc(priv->regs); +} + +static int pic32_uart_probe(struct udevice *dev) +{ + struct pic32_uart_priv *priv = dev_get_platdata(dev); + + pic32_serial_init(priv->regs, priv->uartclk, CONFIG_BAUDRATE); + return 0; +} + +static int pic32_uart_ofdata_to_platdata(struct udevice *dev) +{ + struct pic32_uart_priv *priv = dev_get_platdata(dev); + struct udevice *clkdev; + int ret; + + priv->regs = map_physmem(dev_get_addr(dev), + 0x100, + MAP_NOCACHE); + + /* get clock rate */ + ret = uclass_get_device(UCLASS_CLK, 0, &clkdev); + if (ret) { + printf("clk class not found, %d\n", ret); + return ret; + } + priv->uartclk = clk_get_periph_rate(clkdev, PB2CLK); + + return 0; +} + +static const struct dm_serial_ops pic32_uart_ops = { + .putc = pic32_uart_putc, + .pending = pic32_uart_pending, + .getc = pic32_uart_getc, + .setbrg = pic32_uart_setbrg, +}; + +static const struct udevice_id pic32_uart_ids[] = { + { .compatible = "microchip,pic32mzda-uart" }, + {} +}; + +U_BOOT_DRIVER(pic32_serial) = { + .name = "pic32-uart", + .id = UCLASS_SERIAL, + .of_match = pic32_uart_ids, + .probe = pic32_uart_probe, + .ops = &pic32_uart_ops, + .flags = DM_FLAG_PRE_RELOC, + .ofdata_to_platdata = pic32_uart_ofdata_to_platdata, + .platdata_auto_alloc_size = sizeof(struct pic32_uart_priv), +}; + +#ifdef CONFIG_DEBUG_UART_PIC32 +#include <debug_uart.h> + +static inline void _debug_uart_init(void) +{ + void __iomem *regs = (void __iomem *)CONFIG_DEBUG_UART_BASE; + + pic32_serial_init(regs, CONFIG_DEBUG_UART_CLOCK, CONFIG_BAUDRATE); +} + +static inline void _debug_uart_putc(int ch) +{ + writel(ch, U_TXREG(CONFIG_DEBUG_UART_BASE)); +} + +DEBUG_UART_FUNCS + +#endif