From 66185b3ec9f103fef14e034550102a6f2a58bf57 Mon Sep 17 00:00:00 2001
From: Anup Patel <anup.patel@wdc.com>
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 <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
---
lib/utils/fdt/fdt_helper.c | 43 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)
(limited to 'lib/utils/fdt')
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)
{
--
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