ARM: tegra: clock: Auto-detect PLLP rate in uart init

Tegra3 platform may boot with one of the predefined fixed PLLP
(peripheral PLL) output rates: 216MHz, 408MHz, or 204MHz. This
commit implements auto-detection of PLLP rate, and debug uart
configuration during kernel uart initialization.

Bug 928260

Change-Id: I3fac4c462f28ac3dc1c72c0cc0f8f87fa0a809c4
Reviewed-on: http://git-master/r/75849
Reviewed-by: Krishna Reddy <vdumpa@nvidia.com>
Signed-off-by: Alex Frid <afrid@nvidia.com>
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Reviewed-on: http://git-master/r/77294
Reviewed-by: Automatic_Commit_Validation_User

4 files changed, 28 insertions, 3 deletions

diff --git a/arch/arm/mach-tegra/board-cardhu.c b/arch/arm/mach-tegra/board-cardhu.c
index bea6a6f19882..8bf2501c29c6 100644
--- a/arch/arm/mach-tegra/board-cardhu.c
+++ b/arch/arm/mach-tegra/board-cardhu.c
@@ -1,7 +1,7 @@
 /*
  * arch/arm/mach-tegra/board-cardhu.c
  *
- * Copyright (c) 2011, NVIDIA Corporation.
+ * Copyright (c) 2011-2012, NVIDIA Corporation.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -346,6 +346,8 @@ static void __init uart_debug_init(void)
 			(board_info.board_id == BOARD_E1257))
 				debug_port_id = 1;
 	}
+
+	tegra_init_debug_uart_rate();
 	switch (debug_port_id) {
 	case 0:
 		/* UARTA is the debug port. */
diff --git a/arch/arm/mach-tegra/board-enterprise.c b/arch/arm/mach-tegra/board-enterprise.c
index f631c9b93cb2..9e4ab51926c2 100644
--- a/arch/arm/mach-tegra/board-enterprise.c
+++ b/arch/arm/mach-tegra/board-enterprise.c
@@ -1,7 +1,7 @@
 /*
  * arch/arm/mach-tegra/board-enterprise.c
  *
- * Copyright (c) 2011, NVIDIA Corporation.
+ * Copyright (c) 2011-2012, NVIDIA Corporation.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -395,6 +395,8 @@ static void __init uart_debug_init(void)
 	unsigned long rate;
 	struct clk *c;
 
+	tegra_init_debug_uart_rate();
+
 	/* UARTD is the debug port. */
 	pr_info("Selecting UARTD as the debug console\n");
 	enterprise_uart_devices[3] = &debug_uartd_device;
diff --git a/arch/arm/mach-tegra/devices.c b/arch/arm/mach-tegra/devices.c
index 549db73f1627..39bc04bd2e39 100644
--- a/arch/arm/mach-tegra/devices.c
+++ b/arch/arm/mach-tegra/devices.c
@@ -27,6 +27,7 @@
 #include <linux/platform_data/tegra_usb.h>
 #include <linux/tegra_avp.h>
 #include <linux/nvhost.h>
+#include <linux/clk.h>
 #include <asm/pmu.h>
 #include <mach/irqs.h>
 #include <mach/iomap.h>
@@ -1733,3 +1734,20 @@ struct platform_device tegra_nvmap_device = {
 	.name	= "tegra-nvmap",
 	.id	= -1,
 };
+
+void tegra_init_debug_uart_rate(void)
+{
+	unsigned int uartclk;
+	struct clk *debug_uart_parent = clk_get_sys(NULL, "pll_p");
+
+	BUG_ON(IS_ERR(debug_uart_parent));
+	uartclk = clk_get_rate(debug_uart_parent);
+
+	debug_uarta_platform_data[0].uartclk = uartclk;
+	debug_uartb_platform_data[0].uartclk = uartclk;
+	debug_uartc_platform_data[0].uartclk = uartclk;
+	debug_uartd_platform_data[0].uartclk = uartclk;
+#if !defined(CONFIG_ARCH_TEGRA_2x_SOC)
+	debug_uarte_platform_data[0].uartclk = uartclk;
+#endif
+}
diff --git a/arch/arm/mach-tegra/devices.h b/arch/arm/mach-tegra/devices.h
index 6d7c7cab3cdf..ff93216ce292 100644
--- a/arch/arm/mach-tegra/devices.h
+++ b/arch/arm/mach-tegra/devices.h
@@ -5,7 +5,7 @@
  *	Colin Cross <ccross@android.com>
  *	Erik Gilling <ccross@android.com>
  *
- * Copyright (C) 2010-2011 NVIDIA Corporation.
+ * Copyright (C) 2010-2012 NVIDIA Corporation.
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
@@ -126,4 +126,7 @@ extern struct platform_device debug_uarte_device;
 
 extern struct nvhost_device tegra_disp1_device;
 extern struct platform_device tegra_nvmap_device;
+
+void tegra_init_debug_uart_rate(void);
+
 #endif