lib: utils: serial: Add Cadence UART driver
PATCH v2 1/1 lib: utils: serial: Add Cadence UART driver
Add Cadence UART driver
Signed-off-by Jun Liang Tan <[email protected]>
Signed-off-by Wei Liang Lim <[email protected]>
--- include/sbi_utils/fdt/fdt_helper.h | 4 +- include/sbi_utils/serial/cadence-uart.h | 16 +++ lib/utils/fdt/fdt_helper.c | 6 +- lib/utils/serial/cadence-uart.c | 125 ++++++++++++++++++++++++ lib/utils/serial/fdt_serial_cadence.c | 35 +++++++ lib/utils/serial/fdt_serial_uart8250.c | 2 +- lib/utils/serial/objects.mk | 4 + 7 files changed, 186 insertions(+), 6 deletions(-) create mode 100644 include/sbi_utils/serial/cadence-uart.h create mode 100644 lib/utils/serial/cadence-uart.c create mode 100644 lib/utils/serial/fdt_serial_cadence.c
include/sbi_utils/fdt/fdt_helper.h +2 -2
@@ -65,8 +65,8 @@ int fdt_parse_shakti_uart_node(void *fdt, int nodeoffset,int fdt_parse_sifive_uart_node (void *fdt,int nodeoffset,struct platform_uart_data *uart); -int fdt_parse_uart8250_node (void *fdt,int nodeoffset, -struct platform_uart_data *uart); +int fdt_parse_uart_node (void *fdt,int nodeoffset, +struct platform_uart_data *uart);int fdt_parse_uart8250 (void *fdt,struct platform_uart_data *uart,const char *compatible);
include/sbi_utils/serial/cadence-uart.h new file +16 -0
@@ -0,0 +1,16 @@ +/* +* SPDX-License-Identifier: BSD-2-Clause +* +* Copyright (c) 2022 StarFive Technology Co., Ltd. +* +* Author: Jun Liang Tan <[email protected]> +*/ + +#ifndef __SERIAL_CADENCE_UART_H__ +#define __SERIAL_CADENCE_UART_H__ + +#include <sbi/sbi_types.h> + +int cadence_uart_init (unsigned long base,u32 in_freq,u32 baudrate); + +#endif
lib/utils/fdt/fdt_helper.c +3 -3
@@ -427,8 +427,8 @@ int fdt_parse_sifive_uart_node(void *fdt, int nodeoffset,return 0 ; } -int fdt_parse_uart8250_node (void *fdt,int nodeoffset, -struct platform_uart_data *uart) +int fdt_parse_uart_node (void *fdt,int nodeoffset, +struct platform_uart_data *uart) {int len, rc;const fdt32_t *val;
@@ -492,7 +492,7 @@ int fdt_parse_uart8250(void *fdt, struct platform_uart_data *uart,if (nodeoffset <0 )return nodeoffset; -return fdt_parse_uart8250_node (fdt, nodeoffset, uart); +return fdt_parse_uart_node (fdt, nodeoffset, uart); } int fdt_parse_xlnx_uartlite_node(void *fdt, int nodeoffset,
lib/utils/serial/cadence-uart.c new file +125 -0
125 lines not on this page · raw message
lib/utils/serial/fdt_serial_cadence.c new file +35 -0
@@ -0,0 +1,35 @@ +/* +* SPDX-License-Identifier: BSD-2-Clause +* +* Copyright (c) 2022 StarFive Technology Co., Ltd. +* +* Author: Jun Liang Tan <[email protected]> +*/ + +#include <sbi_utils/fdt/fdt_helper.h> +#include <sbi_utils/serial/fdt_serial.h> +#include <sbi_utils/serial/cadence-uart.h> + +static int serial_cadence_init (void *fdt,int nodeoff, +const struct fdt_match *match) +{ +int rc; +struct platform_uart_data uart; + + rc =fdt_parse_uart_node (fdt, nodeoff, &uart); +if (rc) +return rc; + +return cadence_uart_init (uart.addr, uart.freq, uart.baud); +} + +static const struct fdt_match serial_cadence_match[] = { + { .compatible ="cdns,uart-r1p12" }, + { .compatible ="starfive,jh8100-uart" }, + { }, +}; + +struct fdt_serial fdt_serial_cadence = { + .match_table = serial_cadence_match, + .init = serial_cadence_init +};
lib/utils/serial/fdt_serial_uart8250.c +1 -1
@@ -17,7 +17,7 @@ static int serial_uart8250_init(void *fdt, int nodeoff,int rc;struct platform_uart_data uart; - rc =fdt_parse_uart8250_node (fdt, nodeoff, &uart); + rc =fdt_parse_uart_node (fdt, nodeoff, &uart);if (rc)return rc;
lib/utils/serial/objects.mk +4 -0
@@ -10,6 +10,9 @@ libsbiutils-objs-y += serial/fdt_serial.o libsbiutils-objs-y += serial/fdt_serial_drivers.o +carray-fdt_serial_drivers-y += fdt_serial_cadence +libsbiutils-objs-y += serial/fdt_serial_cadence.o + carray-fdt_serial_drivers-y += fdt_serial_gaisler libsbiutils-objs-y += serial/fdt_serial_gaisler.o
@@ -31,6 +34,7 @@ libsbiutils-objs-y += serial/fdt_serial_uart8250.o carray-fdt_serial_drivers-y += fdt_serial_xlnx_uartlite libsbiutils-objs-y += serial/fdt_serial_xlnx_uartlite.o +libsbiutils-objs-y += serial/cadence-uart.o libsbiutils-objs-y += serial/gaisler-uart.o libsbiutils-objs-y += serial/shakti-uart.o libsbiutils-objs-y += serial/sifive-uart.o
Signature · 1 line
2.37.0
PATCH v2 1/1 lib: utils: serial: Add Cadence UART driver
Quoted 95 lines · Jun Liang Tan
Add Cadence UART driver
Signed-off-by Jun Liang Tan <[email protected]>Signed-off-by Wei Liang Lim <[email protected]>--- include/sbi_utils/fdt/fdt_helper.h | 4 +- include/sbi_utils/serial/cadence-uart.h | 16 +++ lib/utils/fdt/fdt_helper.c | 6 +- lib/utils/serial/cadence-uart.c | 125 ++++++++++++++++++++++++ lib/utils/serial/fdt_serial_cadence.c | 35 +++++++ lib/utils/serial/fdt_serial_uart8250.c | 2 +- lib/utils/serial/objects.mk | 4 + 7 files changed, 186 insertions(+), 6 deletions(-) create mode 100644 include/sbi_utils/serial/cadence-uart.h create mode 100644 lib/utils/serial/cadence-uart.c create mode 100644 lib/utils/serial/fdt_serial_cadence.cinclude/sbi_utils/fdt/fdt_helper.h +2
-2@@ -65,8 +65,8 @@ int fdt_parse_shakti_uart_node(void *fdt, int nodeoffset,int fdt_parse_sifive_uart_node (void *fdt,int nodeoffset,struct platform_uart_data *uart); -int fdt_parse_uart8250_node (void *fdt,int nodeoffset, -struct platform_uart_data *uart); +int fdt_parse_uart_node (void *fdt,int nodeoffset, +struct platform_uart_data *uart);int fdt_parse_uart8250 (void *fdt,struct platform_uart_data *uart,const char *compatible);include/sbi_utils/serial/cadence-uart.h new file +16
-0@@ -0,0 +1,16 @@ +/* +* SPDX-License-Identifier: BSD-2-Clause +* +* Copyright (c) 2022 StarFive Technology Co., Ltd. +* +* Author: Jun Liang Tan <[email protected]> +*/ + +#ifndef __SERIAL_CADENCE_UART_H__ +#define __SERIAL_CADENCE_UART_H__ + +#include <sbi/sbi_types.h> + +int cadence_uart_init (unsigned long base,u32 in_freq,u32 baudrate); + +#endif lib/utils/fdt/fdt_helper.c +3
-3@@ -427,8 +427,8 @@ int fdt_parse_sifive_uart_node(void *fdt, int nodeoffset,return 0 ; } -int fdt_parse_uart8250_node (void *fdt,int nodeoffset, -struct platform_uart_data *uart) +int fdt_parse_uart_node (void *fdt,int nodeoffset, +struct platform_uart_data *uart) {int len, rc;const fdt32_t *val;@@ -492,7 +492,7 @@ int fdt_parse_uart8250(void *fdt, struct platform_uart_data *uart,if (nodeoffset <0 )return nodeoffset; -return fdt_parse_uart8250_node (fdt, nodeoffset, uart); +return fdt_parse_uart_node (fdt, nodeoffset, uart); } int fdt_parse_xlnx_uartlite_node(void *fdt, int nodeoffset,lib/utils/serial/cadence-uart.c new file +11
-0@@ -0,0 +1,125 @@ +/* +* SPDX-License-Identifier: BSD-2-Clause +* +* Copyright (c) 2022 StarFive Technology Co., Ltd. +* +* Author: Jun Liang Tan <[email protected]> +*/ + +#include <sbi/riscv_io.h> +#include <sbi/sbi_console.h> +#include <sbi_utils/serial/cadence-uart.h>
lib/utils/serial/cadence-uart.c line 21
Quoted 10 lines
lib/utils/serial/cadence-uart.c new file +10
-0+ +/* clang-format off */ + +#define UART_REG_OFFSET_CTRL 0x00/* Control register */ +#define UART_REG_OFFSET_MODE 0x04/* Mode register */ +#define UART_REG_OFFSET_CH_STS 0x2C/* Channel status register */ +#define UART_REG_OFFSET_RX_TX_FIFO 0x30/* RX and TX FIFO register */ +#define UART_REG_OFFSET_INT_DIS 0x0C/* Interrupt disable register */ +#define UART_REG_OFFSET_BRG 0x18/* Baud rate generator register */ +#define UART_REG_OFFSET_BRD 0x34/* Baud rate divider register */
Can we please order these in ascending order by offset? Also, do these define names match the manual you used for the register names? I'm looking at B.33 of https://docs.xilinx.com/v/u/en-US/ug585-Zynq-7000-TRM (which I found from a reference from QEMU code). In that manual they use CR for control, MR for mode, etc. Names that match the documentation is generally preferred (but I may be looking at the wrong documentation :-)
lib/utils/serial/cadence-uart.c line 23
Quoted 2 lines
lib/utils/serial/cadence-uart.c new file +2
-0+ +/* Control register, 0x00 */
If we name the flags in a way that associate them with their register then we don't need comments like the one above.
lib/utils/serial/cadence-uart.c line 29
Quoted 6 lines
lib/utils/serial/cadence-uart.c new file +6
-0+#define UART_CR_TX_DIS 0x00000020/* TX disabled, bit 5 */ +#define UART_CR_TX_EN 0x00000010/* TX enabled, bit 4 */ +#define UART_CR_RX_DIS 0x00000008/* RX disabled, bit 3 */ +#define UART_CR_RX_EN 0x00000004/* RX enabled, bit 2*/ +#define UART_CR_TXRST 0x00000002/* TX logic reset, bit 1 */ +#define UART_CR_RXRST 0x00000001/* RX logic reset, bit 0 */
These names match the manual I'm looking at and make it clear we should call the control register offset something like UART_REG_OFFSET_CR or just UART_REG_CR in order for the flags to match up. Also, I would drop the 'bit N' parts of the comments.
lib/utils/serial/cadence-uart.c line 33
Quoted 4 lines
lib/utils/serial/cadence-uart.c new file +4
-0+ +/* Channel status register, 0x2C */ +#define UART_CHSR_TXFULL 0x00000010/* TX FIFO full, bit 4 */ +#define UART_CHSR_RXEMPTY 0x00000002/* RX FIFO empty, bit 1 */
Same comments as for the control register flags.
lib/utils/serial/cadence-uart.c line 39
Quoted 6 lines
lib/utils/serial/cadence-uart.c new file +6
-0+ +/* Mode register, 0x04 */ +#define UART_MR_PARITY_NONE 0x00000020/* No parity set */ + +/* Baud rate generator register, 0x18 */ +#define UART_BRG_CLK_DIVISOR 0x00000001/* baud_sample = sel_clk */
Please align all define columns above (both registers and flags), i.e.
#define DEFNAME DEFVAL /* COMMENT */
should line up all the way down.
Quoted 5 lines
lib/utils/serial/cadence-uart.c new file +5
-0+ +/* clang-format on */ + +static volatile void *uart_base; +static u32 uart_in_freq;
lib/utils/serial/cadence-uart.c line 54
Quoted 10 lines
lib/utils/serial/cadence-uart.c new file +10
-0+static u32 uart_baudrate; + +/** +* Find minimum divisor divides in_freq to max_target_hz; +* Based on SiFive UART driver (sifive-uart.c) +*/ +static inline unsigned int uart_min_clk_divisor (uint64_t in_freq, +uint64_t max_target_hz) +{ +uint64_t quotient = (in_freq + max_target_hz -1 ) / (max_target_hz);
Neither sifive-uart nor this code is checking max_target_hz is non-zero. And, since it can be read from the DT, there's a chance it could be. (Hopefully people building DTs check their nodes have sane values, but we shouldn't count on it.)
I think we should add
if (max_target_hz == 0) return 0;
to this function and the sifive function.
Quoted 38 lines
lib/utils/serial/cadence-uart.c new file +38
-0+/* Avoid underflow */ +if (quotient ==0 ) +return 0 ; +else +return quotient -1 ; +} + +static u32 get_reg (u32 offset) +{ +return readl (uart_base + offset); +} + +static void set_reg (u32 offset,u32 val) +{ +writel (val, uart_base + offset); +} + +static void cadence_uart_putc (char ch) +{ +while (get_reg (UART_REG_OFFSET_CH_STS ) &UART_CHSR_TXFULL ) + ; + +set_reg (UART_REG_OFFSET_RX_TX_FIFO , ch); +} + +static int cadence_uart_getc (void ) +{ +u32 ret =get_reg (UART_REG_OFFSET_CH_STS ); + +if (!(ret &UART_CHSR_RXEMPTY )) +return get_reg (UART_REG_OFFSET_RX_TX_FIFO ); +return -1 ; +} + +static struct sbi_console_device cadence_console = { + .name ="cadence_uart" , + .console_putc = cadence_uart_putc, + .console_getc = cadence_uart_getc
lib/utils/serial/cadence-uart.c line 102
Quoted 10 lines
lib/utils/serial/cadence-uart.c new file +10
-0+}; + +int cadence_uart_init (unsigned long base,u32 in_freq,u32 baudrate) +{ + uart_base = (volatile void *)base; + uart_in_freq = in_freq; + uart_baudrate = baudrate; + +/* Disable interrupts */ +set_reg (UART_REG_OFFSET_INT_DIS ,0xFFFFFFFF );
Please add a blank line here
lib/utils/serial/cadence-uart.c line 104
Quoted 2 lines
lib/utils/serial/cadence-uart.c new file +2
-0+/* Disable TX RX */ +set_reg (UART_REG_OFFSET_CTRL ,UART_CR_TX_DIS |UART_CR_RX_DIS );
and here
lib/utils/serial/cadence-uart.c line 110
Quoted 6 lines
lib/utils/serial/cadence-uart.c new file +6
-0+/* Configure baudrate */ +if (in_freq) { +set_reg (UART_REG_OFFSET_BRG ,UART_BRG_CLK_DIVISOR ); +set_reg (UART_REG_OFFSET_BRD , +uart_min_clk_divisor (in_freq, baudrate)); + }
and here
lib/utils/serial/cadence-uart.c line 113
Quoted 3 lines
lib/utils/serial/cadence-uart.c new file +3
-0+/* Software reset TX RX data path and enable TX RX */ +set_reg (UART_REG_OFFSET_CTRL ,UART_CR_TXRST |UART_CR_RXRST + |UART_CR_TX_EN |UART_CR_RX_EN );
and here
Quoted 91 lines
lib/utils/serial/cadence-uart.c new file +12
-0+/* Set: +* 1 stop bit, bits[07:06] = 0x00, +* no parity set, bits[05:03] = 0x100, +* 8 bits character length, bits[02:01] = 0x00, +* sel_clk = uart_clk, bit[0] = 0x0 +*/ +set_reg (UART_REG_OFFSET_MODE ,UART_MR_PARITY_NONE ); + +sbi_console_set_device (&cadence_console); + +return 0 ; +}lib/utils/serial/fdt_serial_cadence.c new file +35
-0@@ -0,0 +1,35 @@ +/* +* SPDX-License-Identifier: BSD-2-Clause +* +* Copyright (c) 2022 StarFive Technology Co., Ltd. +* +* Author: Jun Liang Tan <[email protected]> +*/ + +#include <sbi_utils/fdt/fdt_helper.h> +#include <sbi_utils/serial/fdt_serial.h> +#include <sbi_utils/serial/cadence-uart.h> + +static int serial_cadence_init (void *fdt,int nodeoff, +const struct fdt_match *match) +{ +int rc; +struct platform_uart_data uart; + + rc =fdt_parse_uart_node (fdt, nodeoff, &uart); +if (rc) +return rc; + +return cadence_uart_init (uart.addr, uart.freq, uart.baud); +} + +static const struct fdt_match serial_cadence_match[] = { + { .compatible ="cdns,uart-r1p12" }, + { .compatible ="starfive,jh8100-uart" }, + { }, +}; + +struct fdt_serial fdt_serial_cadence = { + .match_table = serial_cadence_match, + .init = serial_cadence_init +};lib/utils/serial/fdt_serial_uart8250.c +1
-1@@ -17,7 +17,7 @@ static int serial_uart8250_init(void *fdt, int nodeoff,int rc;struct platform_uart_data uart; - rc =fdt_parse_uart8250_node (fdt, nodeoff, &uart); + rc =fdt_parse_uart_node (fdt, nodeoff, &uart);if (rc)return rc;lib/utils/serial/objects.mk +4
-0@@ -10,6 +10,9 @@ libsbiutils-objs-y += serial/fdt_serial.o libsbiutils-objs-y += serial/fdt_serial_drivers.o +carray-fdt_serial_drivers-y += fdt_serial_cadence +libsbiutils-objs-y += serial/fdt_serial_cadence.o + carray-fdt_serial_drivers-y += fdt_serial_gaisler libsbiutils-objs-y += serial/fdt_serial_gaisler.o@@ -31,6 +34,7 @@ libsbiutils-objs-y += serial/fdt_serial_uart8250.o carray-fdt_serial_drivers-y += fdt_serial_xlnx_uartlite libsbiutils-objs-y += serial/fdt_serial_xlnx_uartlite.o +libsbiutils-objs-y += serial/cadence-uart.o libsbiutils-objs-y += serial/gaisler-uart.o libsbiutils-objs-y += serial/shakti-uart.o libsbiutils-objs-y += serial/sifive-uart.oSignature · 1 line
2.37.0
Thanks,
drew