[U-Boot] [PATCH v3 45/66] rockchip: clk: rk3368: add support for GMAC (SLCK_MAC) clock

Philipp Tomsich
2017-07-28T19:22:17Z

To enable the GMAC on the RK3368, we need to set up the clocking
appropriately to generate a tx_clk for the MAC.

This adds an implementation that implements the use of the <&ext_gmac>
clock (i.e. an external 125MHz clock for RGMII provided by the PHY).
This is the clock setup used by the boards currently supported by
U-Boot (i.e. Geekbox, Sheep and RK3368-uQ7).

This includes the change from commit
- rockchip: clk: rk3368: define GMAC_MUX_SEL_EXTCLK

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>

Reviewed-by: Simon Glass <sjg@chromium.org>
---

Changes in v3: None
Changes in v2: None

arch/arm/include/asm/arch-rockchip/cru_rk3368.h | 3 +++
drivers/clk/rockchip/clk_rk3368.c | 19 +++++++++++++++++--
2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/arch/arm/include/asm/arch-rockchip/cru_rk3368.h b/arch/arm/include/asm/arch-rockchip/cru_rk3368.h
index 21f11e0..2b1197f 100644
--- a/arch/arm/include/asm/arch-rockchip/cru_rk3368.h
+++ b/arch/arm/include/asm/arch-rockchip/cru_rk3368.h
@@ -89,6 +89,9 @@ enum {
MCU_CLK_DIV_SHIFT = 0,
MCU_CLK_DIV_MASK = GENMASK(4, 0),

+ /* CLKSEL43_CON */
+ GMAC_MUX_SEL_EXTCLK = BIT(8),
+
/* CLKSEL51_CON */
MMC_PLL_SEL_SHIFT = 8,
MMC_PLL_SEL_MASK = GENMASK(9, 8),
diff --git a/drivers/clk/rockchip/clk_rk3368.c b/drivers/clk/rockchip/clk_rk3368.c
index 1bed4e2..2b6c8da 100644
--- a/drivers/clk/rockchip/clk_rk3368.c
+++ b/drivers/clk/rockchip/clk_rk3368.c
@@ -338,6 +338,19 @@ static ulong rk3368_ddr_set_clk(struct rk3368_cru *cru, ulong set_rate)
}
#endif

+#if CONFIG_IS_ENABLED(GMAC_ROCKCHIP)
+static ulong rk3368_gmac_set_clk(struct rk3368_cru *cru,
+ ulong clk_id, ulong set_rate)
+{
+ /*
+ * This models the 'assigned-clock-parents = <&ext_gmac>' from
+ * the DTS and switches to the 'ext_gmac' clock parent.
+ */
+ rk_setreg(&cru->clksel_con[43], GMAC_MUX_SEL_EXTCLK);
+ return set_rate;
+}
+#endif
+
static ulong rk3368_clk_set_rate(struct clk *clk, ulong rate)
{
struct rk3368_clk_priv *priv = dev_get_priv(clk->dev);
@@ -356,10 +369,12 @@ static ulong rk3368_clk_set_rate(struct clk *clk, ulong rate)
ret = rk3368_mmc_set_clk(clk, rate);
break;
#endif
+#if CONFIG_IS_ENABLED(GMAC_ROCKCHIP)
case SCLK_MAC:
- /* nothing to do, as this is an external clock */
- ret = rate;
+ /* select the external clock */
+ ret = rk3368_gmac_set_clk(priv->cru, clk->id, rate);
break;
+#endif
default:
return -ENOENT;
}
--
2.1.4