rockchip: clk: rk3188: Allow configuration of the armclk
authorHeiko Stübner <heiko@sntech.de>
Mon, 20 Mar 2017 11:40:32 +0000 (12:40 +0100)
committerSimon Glass <sjg@chromium.org>
Wed, 5 Apr 2017 02:01:57 +0000 (20:01 -0600)
The armclk starts in slow mode (24MHz) on the rk3188, which makes the whole
startup take a lot of time. We therefore want to at least move to the safe
600MHz value we can use with default pmic settings.
This is also the freqency the proprietary sdram-init leaves the cpu at.

For boards that have pmic control later in u-boot, we also add the option
to set the maximum frequency of 1.6GHz, if they so desire.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Simon Glass <sjg@chromium.org>
arch/arm/include/asm/arch-rockchip/cru_rk3188.h
drivers/clk/rockchip/clk_rk3188.c

index 74f0fedcc64d5529c069f71fb7646801dbce871a..f5d6420d0434888e3e7311b37c533efd2eb68ff5 100644 (file)
@@ -9,6 +9,7 @@
 #define OSC_HZ         (24 * 1000 * 1000)
 
 #define APLL_HZ                (1608 * 1000000)
+#define APLL_SAFE_HZ   (600 * 1000000)
 #define GPLL_HZ                (594 * 1000000)
 #define CPLL_HZ                (384 * 1000000)
 
index 459649f7248ba448e2758367b3fcf777efc7238c..d36cf8f3f27631c5b03766f1d20722f9cd48dd5e 100644 (file)
@@ -168,6 +168,65 @@ static int rkclk_configure_ddr(struct rk3188_cru *cru, struct rk3188_grf *grf,
        return 0;
 }
 
+static int rkclk_configure_cpu(struct rk3188_cru *cru, struct rk3188_grf *grf,
+                             unsigned int hz, bool has_bwadj)
+{
+       static const struct pll_div apll_cfg[] = {
+               {.nf = 50, .nr = 1, .no = 2},
+               {.nf = 67, .nr = 1, .no = 1},
+       };
+       int div_core_peri, div_aclk_core, cfg;
+
+       /*
+        * We support two possible frequencies, the safe 600MHz
+        * which will work with default pmic settings and will
+        * be set in SPL to get away from the 24MHz default and
+        * the maximum of 1.6Ghz, which boards can set if they
+        * were able to get pmic support for it.
+        */
+       switch (hz) {
+       case APLL_SAFE_HZ:
+               cfg = 0;
+               div_core_peri = 1;
+               div_aclk_core = 3;
+               break;
+       case APLL_HZ:
+               cfg = 1;
+               div_core_peri = 2;
+               div_aclk_core = 3;
+               break;
+       default:
+               debug("Unsupported ARMCLK frequency");
+               return -EINVAL;
+       }
+
+       /* pll enter slow-mode */
+       rk_clrsetreg(&cru->cru_mode_con, APLL_MODE_MASK << APLL_MODE_SHIFT,
+                    APLL_MODE_SLOW << APLL_MODE_SHIFT);
+
+       rkclk_set_pll(cru, CLK_ARM, &apll_cfg[cfg], has_bwadj);
+
+       /* waiting for pll lock */
+       while (!(readl(&grf->soc_status0) & SOCSTS_APLL_LOCK))
+               udelay(1);
+
+       /* Set divider for peripherals attached to the cpu core. */
+       rk_clrsetreg(&cru->cru_clksel_con[0],
+               CORE_PERI_DIV_MASK << CORE_PERI_DIV_SHIFT,
+               div_core_peri << CORE_PERI_DIV_SHIFT);
+
+       /* set up dependent divisor for aclk_core */
+       rk_clrsetreg(&cru->cru_clksel_con[1],
+               CORE_ACLK_DIV_MASK << CORE_ACLK_DIV_SHIFT,
+               div_aclk_core << CORE_ACLK_DIV_SHIFT);
+
+       /* PLL enter normal-mode */
+       rk_clrsetreg(&cru->cru_mode_con, APLL_MODE_MASK << APLL_MODE_SHIFT,
+                    APLL_MODE_NORMAL << APLL_MODE_SHIFT);
+
+       return hz;
+}
+
 /* Get pll rate by id */
 static uint32_t rkclk_pll_get_rate(struct rk3188_cru *cru,
                                   enum rk_clk_id clk_id)
@@ -435,6 +494,10 @@ static ulong rk3188_clk_set_rate(struct clk *clk, ulong rate)
        ulong new_rate;
 
        switch (clk->id) {
+       case PLL_APLL:
+               new_rate = rkclk_configure_cpu(priv->cru, priv->grf, rate,
+                                              priv->has_bwadj);
+               break;
        case CLK_DDR:
                new_rate = rkclk_configure_ddr(priv->cru, priv->grf, rate,
                                               priv->has_bwadj);