Parametrize baudrate and UART clock during console_init()
This patch adds baud rate and UART clock frequency as parameters
to the pl011 driver api console_init(). This allows each platform
to specify UART clock and baud rate according to their specific
hardware implementation.
Fixes ARM-software/tf-issues#215
Change-Id: Id13eef70a1c530e709b34dd1e6eb84db0797ced2
diff --git a/drivers/arm/pl011/pl011_console.S b/drivers/arm/pl011/pl011_console.S
index bf26b6b..5ff1582 100644
--- a/drivers/arm/pl011/pl011_console.S
+++ b/drivers/arm/pl011/pl011_console.S
@@ -47,53 +47,56 @@
.section .data.console_base ; .align 3
console_base: .quad 0x0
- /* ---------------------------------------------
- * int console_init(unsigned long base_addr)
+ /* -----------------------------------------------
+ * int console_init(unsigned long base_addr,
+ * unsigned int uart_clk, unsigned int baud_rate)
* Function to initialize the console without a
* C Runtime to print debug information. It saves
* the console base to the data section.
* In: x0 - console base address
+ * w1 - Uart clock in Hz
+ * w2 - Baud rate
* out: return 1 on success.
- * Clobber list : x1, x2
- * ---------------------------------------------
+ * Clobber list : x1 - x3
+ * -----------------------------------------------
*/
func console_init
- adrp x1, console_base
- str x0, [x1, :lo12:console_base]
+ adrp x3, console_base
+ str x0, [x3, :lo12:console_base]
b console_core_init
- /* ---------------------------------------------
- * int console_core_init(unsigned long base_addr)
+ /* -----------------------------------------------
+ * int console_core_init(unsigned long base_addr,
+ * unsigned int uart_clk, unsigned int baud_rate)
* Function to initialize the console without a
* C Runtime to print debug information. This
* function will be accessed by console_init and
* crash reporting.
* In: x0 - console base address
+ * w1 - Uart clock in Hz
+ * w2 - Baud rate
* Out: return 1 on success
* Clobber list : x1, x2
- * ---------------------------------------------
+ * -----------------------------------------------
*/
func console_core_init
/* Check the input base address */
cbz x0, init_fail
+ /* Check baud rate and uart clock for sanity */
+ cbz w1, init_fail
+ cbz w2, init_fail
/* Program the baudrate */
-#if defined(PL011_INTEGER) && defined(PL011_FRACTIONAL)
- mov w1, #PL011_INTEGER
- str w1, [x0, #UARTIBRD]
- mov w1, #PL011_FRACTIONAL
- str w1, [x0, #UARTFBRD]
-#else
-.set BRD, ((PL011_CLK_IN_HZ << 2) / PL011_BAUDRATE)
+ /* Divisor = (Uart clock * 4) / baudrate */
+ lsl w1, w1, #2
+ udiv w2, w1, w2
+ /* IBRD = Divisor >> 6 */
+ lsr w1, w2, #6
/* Write the IBRD */
- mov w1, #((BRD >> 6) & 0xffff)
-.if BRD>=0x400000
- movk w1, #(BRD >> 22), LSL #16
-.endif
str w1, [x0, #UARTIBRD]
+ /* FBRD = Divisor & 0x3F */
+ and w1, w2, #0x3f
/* Write the FBRD */
- mov w1, #(BRD & 0x3f)
str w1, [x0, #UARTFBRD]
-#endif
mov w1, #PL011_LINE_CONTROL
str w1, [x0, #UARTLCR_H]
/* Clear any pending errors */
@@ -121,10 +124,10 @@
b console_core_putc
/* --------------------------------------------------------
- * int console_core_putc(int c, unsigned long base_addr)
+ * int console_core_putc(int c, unsigned int base_addr)
* Function to output a character over the console. It
* returns the character printed on success or -1 on error.
- * In : x0 - character to be printed
+ * In : w0 - character to be printed
* x1 - console base address
* Out : return -1 on error else return character.
* Clobber list : x2
@@ -134,7 +137,7 @@
/* Check the input parameter */
cbz x1, putc_error
/* Prepend '\r' to '\n' */
- cmp x0, #0xA
+ cmp w0, #0xA
b.ne 2f
1:
/* Check if the transmit FIFO is full */