To implement a TPL stage (incl. its DRAM controller setup) for the RK3368, we'll want to configure the DPLL (DRAM PLL).
This commit implements setting the DPLL (CLK_DDR) and provides PLL configuration details for the common DRAM operating speeds found on RK3368 boards.
Signed-off-by: Philipp Tomsich philipp.tomsich@theobroma-systems.com
Reviewed-by: Simon Glass sjg@chromium.org ---
Changes in v4: None Changes in v3: None Changes in v2: None
drivers/clk/rockchip/clk_rk3368.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+)
diff --git a/drivers/clk/rockchip/clk_rk3368.c b/drivers/clk/rockchip/clk_rk3368.c index d05be72..33d2946 100644 --- a/drivers/clk/rockchip/clk_rk3368.c +++ b/drivers/clk/rockchip/clk_rk3368.c @@ -250,6 +250,37 @@ static ulong rk3368_clk_get_rate(struct clk *clk) return rate; }
+static ulong rk3368_ddr_set_clk(struct rk3368_cru *cru, ulong set_rate) +{ + const struct pll_div *dpll_cfg = NULL; + const ulong MHz = 1000000; + + /* Fout = ((Fin /NR) * NF )/ NO */ + static const struct pll_div dpll_1200 = + PLL_DIVISORS(1200 * MHz, 1, 1); + static const struct pll_div dpll_1332 = + PLL_DIVISORS(1332 * MHz, 2, 1); + static const struct pll_div dpll_1600 = + PLL_DIVISORS(1600 * MHz, 3, 2); + + switch (set_rate) { + case 1200*MHz: + dpll_cfg = &dpll_1200; + break; + case 1332*MHz: + dpll_cfg = &dpll_1332; + break; + case 1600*MHz: + dpll_cfg = &dpll_1600; + break; + default: + error("Unsupported SDRAM frequency!,%ld\n", set_rate); + } + rkclk_set_pll(cru, DPLL, dpll_cfg); + + return set_rate; +} + static ulong rk3368_clk_set_rate(struct clk *clk, ulong rate) { struct rk3368_clk_priv *priv = dev_get_priv(clk->dev); @@ -257,6 +288,10 @@ static ulong rk3368_clk_set_rate(struct clk *clk, ulong rate)
debug("%s id:%ld rate:%ld\n", __func__, clk->id, rate); switch (clk->id) { + case CLK_DDR: + ret = rk3368_ddr_set_clk(priv->cru, rate); + break; + case SCLK_SDMMC: case SCLK_EMMC: ret = rk3368_mmc_set_clk(priv->cru, clk->id, rate);