From 66185b3ec9f103fef14e034550102a6f2a58bf57 Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Sat, 25 Apr 2020 18:50:37 +0530 Subject: lib: utils: Add fdt_parse_sifive_uart_node() function We add fdt_parse_sifive_uart_node() function which will allow us to parse a particular DT node as SiFive UART node. This will be useful in parsing the node pointed by stdout-path. Signed-off-by: Anup Patel Reviewed-by: Alistair Francis Reviewed-by: Atish Patra --- lib/utils/fdt/fdt_helper.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'lib/utils') diff --git a/lib/utils/fdt/fdt_helper.c b/lib/utils/fdt/fdt_helper.c index 8fe4ace..3186f64 100644 --- a/lib/utils/fdt/fdt_helper.c +++ b/lib/utils/fdt/fdt_helper.c @@ -18,6 +18,11 @@ #define DEFAULT_UART_REG_SHIFT 0 #define DEFAULT_UART_REG_IO_WIDTH 1 +#define DEFAULT_SIFIVE_UART_FREQ 0 +#define DEFAULT_SIFIVE_UART_BAUD 115200 +#define DEFAULT_SIFIVE_UART_REG_SHIFT 0 +#define DEFAULT_SIFIVE_UART_REG_IO_WIDTH 4 + const struct fdt_match *fdt_match_node(void *fdt, int nodeoff, const struct fdt_match *match_table) { @@ -99,6 +104,44 @@ int fdt_get_node_addr_size(void *fdt, int node, unsigned long *addr, return 0; } +int fdt_parse_sifive_uart_node(void *fdt, int nodeoffset, + struct platform_uart_data *uart) +{ + int len, rc; + const fdt32_t *val; + unsigned long reg_addr, reg_size; + + if (nodeoffset < 0 || !uart || !fdt) + return SBI_ENODEV; + + rc = fdt_get_node_addr_size(fdt, nodeoffset, ®_addr, ®_size); + if (rc < 0 || !reg_addr || !reg_size) + return SBI_ENODEV; + uart->addr = reg_addr; + + /** + * UART address is mandaotry. clock-frequency and current-speed + * may not be present. Don't return error. + */ + val = (fdt32_t *)fdt_getprop(fdt, nodeoffset, "clock-frequency", &len); + if (len > 0 && val) + uart->freq = fdt32_to_cpu(*val); + else + uart->freq = DEFAULT_SIFIVE_UART_FREQ; + + val = (fdt32_t *)fdt_getprop(fdt, nodeoffset, "current-speed", &len); + if (len > 0 && val) + uart->baud = fdt32_to_cpu(*val); + else + uart->baud = DEFAULT_SIFIVE_UART_BAUD; + + /* For SiFive UART, the reg-shift and reg-io-width are fixed .*/ + uart->reg_shift = DEFAULT_SIFIVE_UART_REG_SHIFT; + uart->reg_io_width = DEFAULT_SIFIVE_UART_REG_IO_WIDTH; + + return 0; +} + int fdt_parse_uart8250_node(void *fdt, int nodeoffset, struct platform_uart_data *uart) { -- cgit v1.2.3