[U-Boot] [PATCH 2/4] macb: support higher rate GEM MDIO clock divisors

[Dave Aldridge]

GEM devices support larger clock divisors and have a different
range of divisors.  Program the MDIO clock divisors based on the
device type.

Signed-off-by: Dave Aldridge <fovsoft at gmail.com>
---
 drivers/net/macb.c |   63 ++++++++++++++++++++++++++++++++++++++--------------
 drivers/net/macb.h |   12 ++++++++++
 2 files changed, 58 insertions(+), 17 deletions(-)

diff --git a/drivers/net/macb.c b/drivers/net/macb.c
index d52dda0..fd99cdb 100644
--- a/drivers/net/macb.c
+++ b/drivers/net/macb.c
@@ -532,11 +532,52 @@ static int macb_write_hwaddr(struct eth_device *dev)
 	return 0;
 }
 
+static u32 gem_mdc_clk_div(int id)
+{
+	u32 ncfgr;
+	unsigned long pclk_hz = get_macb_pclk_rate(id);
+
+	if (pclk_hz <= 20000000)
+		ncfgr = GEM_BF(CLK, GEM_CLK_DIV8);
+	else if (pclk_hz <= 40000000)
+		ncfgr = GEM_BF(CLK, GEM_CLK_DIV16);
+	else if (pclk_hz <= 80000000)
+		ncfgr = GEM_BF(CLK, GEM_CLK_DIV32);
+	else if (pclk_hz <= 120000000)
+		ncfgr = GEM_BF(CLK, GEM_CLK_DIV48);
+	else if (pclk_hz <= 160000000)
+		ncfgr = GEM_BF(CLK, GEM_CLK_DIV64);
+	else
+		ncfgr = GEM_BF(CLK, GEM_CLK_DIV96);
+
+	return ncfgr;
+}
+
+static u32 macb_mdc_clk_div(struct macb_device *macb, int id)
+{
+	u32 ncfgr;
+	unsigned long pclk_hz;
+
+	if (macb->is_gem)
+		return gem_mdc_clk_div(id);
+
+	pclk_hz = get_macb_pclk_rate(id);
+	if (pclk_hz <= 20000000)
+		ncfgr = MACB_BF(CLK, MACB_CLK_DIV8);
+	else if (pclk_hz <= 40000000)
+		ncfgr = MACB_BF(CLK, MACB_CLK_DIV16);
+	else if (pclk_hz <= 80000000)
+		ncfgr = MACB_BF(CLK, MACB_CLK_DIV32);
+	else
+		ncfgr = MACB_BF(CLK, MACB_CLK_DIV64);
+
+	return ncfgr;
+}
+
 int macb_eth_initialize(int id, void *regs, unsigned int phy_addr)
 {
 	struct macb_device *macb;
 	struct eth_device *netdev;
-	unsigned long macb_hz;
 	u32 ncfgr;
 
 	macb = malloc(sizeof(struct macb_device));
@@ -567,26 +608,14 @@ int macb_eth_initialize(int id, void *regs, unsigned int phy_addr)
 	netdev->recv = macb_recv;
 	netdev->write_hwaddr = macb_write_hwaddr;
 
-	/*
-	 * Do some basic initialization so that we at least can talk
-	 * to the PHY
-	 */
-	macb_hz = get_macb_pclk_rate(id);
-	if (macb_hz < 20000000)
-		ncfgr = MACB_BF(CLK, MACB_CLK_DIV8);
-	else if (macb_hz < 40000000)
-		ncfgr = MACB_BF(CLK, MACB_CLK_DIV16);
-	else if (macb_hz < 80000000)
-		ncfgr = MACB_BF(CLK, MACB_CLK_DIV32);
-	else
-		ncfgr = MACB_BF(CLK, MACB_CLK_DIV64);
-
-	macb_writel(macb, NCFGR, ncfgr);
-
 	/* Cadence GEM has a module ID of 2. */
 	if (MACB_BFEXT(IDNUM, macb_readl(macb, MID)) == 0x2)
 		macb->is_gem = 1;
 
+	/* Set MII management clock divider */
+	ncfgr = macb_mdc_clk_div(macb, id);
+	macb_writel(macb, NCFGR, ncfgr);
+
 	eth_register(netdev);
 
 #if defined(CONFIG_CMD_MII)
diff --git a/drivers/net/macb.h b/drivers/net/macb.h
index a2913f2..b08a057 100644
--- a/drivers/net/macb.h
+++ b/drivers/net/macb.h
@@ -147,6 +147,10 @@
 #define MACB_IRXFCS_OFFSET			19
 #define MACB_IRXFCS_SIZE			1
 
+/* GEM specific NCFGR bitfields. */
+#define GEM_CLK_OFFSET				18
+#define GEM_CLK_SIZE				3
+
 /* Bitfields in NSR */
 #define MACB_NSR_LINK_OFFSET			0
 #define MACB_NSR_LINK_SIZE			1
@@ -261,6 +265,14 @@
 #define MACB_CLK_DIV32				2
 #define MACB_CLK_DIV64				3
 
+/* GEM specific constants for CLK. */
+#define GEM_CLK_DIV8				0
+#define GEM_CLK_DIV16				1
+#define GEM_CLK_DIV32				2
+#define GEM_CLK_DIV48				3
+#define GEM_CLK_DIV64				4
+#define GEM_CLK_DIV96				5
+
 /* Constants for MAN register */
 #define MACB_MAN_SOF				1
 #define MACB_MAN_WRITE				1
-- 
1.7.3.4