serial, mfd: don't hardcode the console

Add support to specify which HSU port to use as an early console. This can
be selected by passing "earlyprintk=hsu<n>" on the kernel command line. By
default port 0 is still used.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 14 insertions, 6 deletions

diff --git a/arch/x86/include/asm/mrst.h b/arch/x86/include/asm/mrst.h
index 719f00b28ff5..470776039af9 100644
--- a/arch/x86/include/asm/mrst.h
+++ b/arch/x86/include/asm/mrst.h
@@ -51,7 +51,7 @@ extern struct console early_mrst_console;
 extern void mrst_early_console_init(void);
 
 extern struct console early_hsu_console;
-extern void hsu_early_console_init(void);
+extern void hsu_early_console_init(const char *);
 
 extern void intel_scu_devices_create(void);
 extern void intel_scu_devices_destroy(void);
diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c
index cd28a350f7f9..9d42a52d2331 100644
--- a/arch/x86/kernel/early_printk.c
+++ b/arch/x86/kernel/early_printk.c
@@ -247,7 +247,7 @@ static int __init setup_early_printk(char *buf)
                 }
 
                 if (!strncmp(buf, "hsu", 3)) {
-                        hsu_early_console_init();
+                        hsu_early_console_init(buf + 3);
                         early_console_register(&early_hsu_console, keep);
                 }
 #endif
diff --git a/arch/x86/platform/mrst/early_printk_mrst.c b/arch/x86/platform/mrst/early_printk_mrst.c
index 25bfdbb5b130..3c6e328483c7 100644
--- a/arch/x86/platform/mrst/early_printk_mrst.c
+++ b/arch/x86/platform/mrst/early_printk_mrst.c
@@ -245,16 +245,24 @@ struct console early_mrst_console = {
  * Following is the early console based on Medfield HSU (High
  * Speed UART) device.
  */
-#define HSU_PORT2_PADDR         0xffa28180
+#define HSU_PORT_BASE           0xffa28080
 
 static void __iomem *phsu;
 
-void hsu_early_console_init(void)
+void hsu_early_console_init(const char *s)
 {
+        unsigned long paddr, port = 0;
         u8 lcr;
 
-        phsu = (void *)set_fixmap_offset_nocache(FIX_EARLYCON_MEM_BASE,
-                                                        HSU_PORT2_PADDR);
+        /*
+         * Select the early HSU console port if specified by user in the
+         * kernel command line.
+         */
+        if (*s && !kstrtoul(s, 10, &port))
+                port = clamp_val(port, 0, 2);
+
+        paddr = HSU_PORT_BASE + port * 0x80;
+        phsu = (void *)set_fixmap_offset_nocache(FIX_EARLYCON_MEM_BASE, paddr);
 
         /* Disable FIFO */
         writeb(0x0, phsu + UART_FCR);