arm: bcm281xx: Add Ethernet Clock support

Enable Ethernet clock when Broadcom StarFighter2 Ethernet block
(CONFIG_BCM_SF2_ETH) is enabled.

Signed-off-by: Jiandong Zheng <jdzheng@broadcom.com>
Signed-off-by: Steve Rae <srae@broadcom.com>
diff --git a/arch/arm/cpu/armv7/bcm281xx/clk-eth.c b/arch/arm/cpu/armv7/bcm281xx/clk-eth.c
new file mode 100644
index 0000000..b0b92b9
--- /dev/null
+++ b/arch/arm/cpu/armv7/bcm281xx/clk-eth.c
@@ -0,0 +1,143 @@
+/*
+ * Copyright 2014 Broadcom Corporation.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/errno.h>
+#include <asm/arch/sysmap.h>
+#include <asm/kona-common/clk.h>
+#include "clk-core.h"
+
+#define WR_ACCESS_ADDR			ESUB_CLK_BASE_ADDR
+#define WR_ACCESS_PASSWORD				0xA5A500
+
+#define PLLE_POST_RESETB_ADDR		(ESUB_CLK_BASE_ADDR + 0x00000C00)
+
+#define PLLE_RESETB_ADDR		(ESUB_CLK_BASE_ADDR + 0x00000C58)
+#define PLLE_RESETB_I_PLL_RESETB_PLLE_MASK		0x00010000
+#define PLLE_POST_RESETB_I_POST_RESETB_PLLE_MASK	0x00000001
+
+#define PLL_LOCK_ADDR			(ESUB_CLK_BASE_ADDR + 0x00000C38)
+#define PLL_LOCK_PLL_LOCK_PLLE_MASK			0x00000001
+
+#define ESW_SYS_DIV_ADDR		(ESUB_CLK_BASE_ADDR + 0x00000A04)
+#define ESW_SYS_DIV_PLL_SELECT_MASK			0x00000300
+#define ESW_SYS_DIV_DIV_MASK				0x0000001C
+#define ESW_SYS_DIV_PLL_VAR_208M_CLK_SELECT		0x00000100
+#define ESW_SYS_DIV_DIV_SELECT				0x4
+#define ESW_SYS_DIV_TRIGGER_MASK			0x00000001
+
+#define ESUB_AXI_DIV_DEBUG_ADDR		(ESUB_CLK_BASE_ADDR + 0x00000E04)
+#define ESUB_AXI_DIV_DEBUG_PLL_SELECT_MASK		0x0000001C
+#define ESUB_AXI_DIV_DEBUG_PLL_SELECT_OVERRIDE_MASK	0x00000040
+#define ESUB_AXI_DIV_DEBUG_PLL_VAR_208M_CLK_SELECT	0x0
+#define ESUB_AXI_DIV_DEBUG_TRIGGER_MASK			0x00000001
+
+#define PLL_MAX_RETRY	100
+
+/* Enable appropriate clocks for Ethernet */
+int clk_eth_enable(void)
+{
+	int rc = -1;
+	int retry_count = 0;
+	rc = clk_get_and_enable("esub_ccu_clk");
+
+	/* Enable Access to CCU registers */
+	writel((1 | WR_ACCESS_PASSWORD), WR_ACCESS_ADDR);
+
+	writel(readl(PLLE_POST_RESETB_ADDR) &
+	       ~PLLE_POST_RESETB_I_POST_RESETB_PLLE_MASK,
+	       PLLE_POST_RESETB_ADDR);
+
+	/* Take PLL out of reset and put into normal mode */
+	writel(readl(PLLE_RESETB_ADDR) | PLLE_RESETB_I_PLL_RESETB_PLLE_MASK,
+	       PLLE_RESETB_ADDR);
+
+	/* Wait for PLL lock */
+	rc = -1;
+	while (retry_count < PLL_MAX_RETRY) {
+		udelay(100);
+		if (readl(PLL_LOCK_ADDR) & PLL_LOCK_PLL_LOCK_PLLE_MASK) {
+			rc = 0;
+			break;
+		}
+		retry_count++;
+	}
+
+	if (rc == -1) {
+		printf("%s: ETH-PLL lock timeout, Ethernet is not enabled!\n",
+		       __func__);
+		return -1;
+	}
+
+	writel(readl(PLLE_POST_RESETB_ADDR) |
+	       PLLE_POST_RESETB_I_POST_RESETB_PLLE_MASK,
+	       PLLE_POST_RESETB_ADDR);
+
+	/* Switch esw_sys_clk to use 104MHz(208MHz/2) clock */
+	writel((readl(ESW_SYS_DIV_ADDR) &
+		~(ESW_SYS_DIV_PLL_SELECT_MASK | ESW_SYS_DIV_DIV_MASK)) |
+	       ESW_SYS_DIV_PLL_VAR_208M_CLK_SELECT | ESW_SYS_DIV_DIV_SELECT,
+	       ESW_SYS_DIV_ADDR);
+
+	writel(readl(ESW_SYS_DIV_ADDR) | ESW_SYS_DIV_TRIGGER_MASK,
+	       ESW_SYS_DIV_ADDR);
+
+	/* Wait for trigger complete */
+	rc = -1;
+	retry_count = 0;
+	while (retry_count < PLL_MAX_RETRY) {
+		udelay(100);
+		if (!(readl(ESW_SYS_DIV_ADDR) & ESW_SYS_DIV_TRIGGER_MASK)) {
+			rc = 0;
+			break;
+		}
+		retry_count++;
+	}
+
+	if (rc == -1) {
+		printf("%s: SYS CLK Trigger timeout, Ethernet is not enabled!\n",
+		       __func__);
+		return -1;
+	}
+
+	/* switch Esub AXI clock to 208MHz */
+	writel((readl(ESUB_AXI_DIV_DEBUG_ADDR) &
+		~(ESUB_AXI_DIV_DEBUG_PLL_SELECT_MASK |
+		  ESUB_AXI_DIV_DEBUG_PLL_SELECT_OVERRIDE_MASK |
+		  ESUB_AXI_DIV_DEBUG_TRIGGER_MASK)) |
+	       ESUB_AXI_DIV_DEBUG_PLL_VAR_208M_CLK_SELECT |
+	       ESUB_AXI_DIV_DEBUG_PLL_SELECT_OVERRIDE_MASK,
+	       ESUB_AXI_DIV_DEBUG_ADDR);
+
+	writel(readl(ESUB_AXI_DIV_DEBUG_ADDR) |
+	       ESUB_AXI_DIV_DEBUG_TRIGGER_MASK,
+	       ESUB_AXI_DIV_DEBUG_ADDR);
+
+	/* Wait for trigger complete */
+	rc = -1;
+	retry_count = 0;
+	while (retry_count < PLL_MAX_RETRY) {
+		udelay(100);
+		if (!(readl(ESUB_AXI_DIV_DEBUG_ADDR) &
+		      ESUB_AXI_DIV_DEBUG_TRIGGER_MASK)) {
+			rc = 0;
+			break;
+		}
+		retry_count++;
+	}
+
+	if (rc == -1) {
+		printf("%s: AXI CLK Trigger timeout, Ethernet is not enabled!\n",
+		       __func__);
+		return -1;
+	}
+
+	/* Disable Access to CCU registers */
+	writel(WR_ACCESS_PASSWORD, WR_ACCESS_ADDR);
+
+	return rc;
+}