MIPS: Alchemy: platform: use clk framework for uarts

Use the clock framework to get the rate of the peripheral clock.
Remove the now obsolete get_uart_baud_base function.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/7468/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/alchemy/common/clocks.c

@@ -38,7 +38,6 @@
 #define AU1000_SRC_CLK	12000000
 
 static unsigned int au1x00_clock; /*  Hz */
-static unsigned long uart_baud_base;
 
 /*
  * Set the au1000_clock
@@ -54,21 +53,6 @@ unsigned int get_au1x00_speed(void)
 }
 EXPORT_SYMBOL(get_au1x00_speed);
 
-/*
- * The UART baud base is not known at compile time ... if
- * we want to be able to use the same code on different
- * speed CPUs.
- */
-unsigned long get_au1x00_uart_baud_base(void)
-{
-	return uart_baud_base;
-}
-
-void set_au1x00_uart_baud_base(unsigned long new_baud_base)
-{
-	uart_baud_base = new_baud_base;
-}
-
 /*
  * We read the real processor speed from the PLL.  This is important
  * because it is more accurate than computing it from the 32 KHz
@@ -95,9 +79,6 @@ unsigned long au1xxx_calc_clock(void)
 
 	/* On Alchemy CPU:counter ratio is 1:1 */
 	mips_hpt_frequency = cpu_speed;
-	/* Equation: Baudrate = CPU / (SD * 2 * CLKDIV * 16) */
-	set_au1x00_uart_baud_base(cpu_speed / (2 *
-		((alchemy_rdsys(AU1000_SYS_POWERCTRL) & 0x03) + 2) * 16));
 
 	set_au1x00_speed(cpu_speed);
 

arch/mips/alchemy/common/platform.c

@@ -11,6 +11,7 @@
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/clk.h>
 #include <linux/dma-mapping.h>
 #include <linux/etherdevice.h>
 #include <linux/init.h>
@@ -99,10 +100,20 @@ static struct platform_device au1xx0_uart_device = {
 
 static void __init alchemy_setup_uarts(int ctype)
 {
-	unsigned int uartclk = get_au1x00_uart_baud_base() * 16;
+	long uartclk;
 	int s = sizeof(struct plat_serial8250_port);
 	int c = alchemy_get_uarts(ctype);
 	struct plat_serial8250_port *ports;
+	struct clk *clk = clk_get(NULL, ALCHEMY_PERIPH_CLK);
+
+	if (IS_ERR(clk))
+		return;
+	if (clk_prepare_enable(clk)) {
+		clk_put(clk);
+		return;
+	}
+	uartclk = clk_get_rate(clk);
+	clk_put(clk);
 
 	ports = kzalloc(s * (c + 1), GFP_KERNEL);
 	if (!ports) {

arch/mips/include/asm/mach-au1x00/au1000.h

@@ -844,8 +844,6 @@ static inline int alchemy_get_macs(int type)
 /* arch/mips/au1000/common/clocks.c */
 extern void set_au1x00_speed(unsigned int new_freq);
 extern unsigned int get_au1x00_speed(void);
-extern void set_au1x00_uart_baud_base(unsigned long new_baud_base);
-extern unsigned long get_au1x00_uart_baud_base(void);
 extern unsigned long au1xxx_calc_clock(void);
 
 /* PM: arch/mips/alchemy/common/sleeper.S, power.c, irq.c */