[U-Boot] [PATCH v3 38/66] rockchip: clk: rk3368: implement bandwidth adjust for PLLs

Philipp Tomsich
2017-07-28T19:22:10Z

The RK3368 TRM recommends to configure the bandwith adjustment (CON2)
for PLLs to NF/2. This implements this for all reconfigurations of
PLLs and removes the 'has_bwadj' flag (as the RK3368 always has the
bandwidth-adjustment feature according to its manual).

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

drivers/clk/rockchip/clk_rk3368.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/rockchip/clk_rk3368.c b/drivers/clk/rockchip/clk_rk3368.c
index e1d9aeb..d8f06d5 100644
--- a/drivers/clk/rockchip/clk_rk3368.c
+++ b/drivers/clk/rockchip/clk_rk3368.c
@@ -1,6 +1,7 @@
/*
* (C) Copyright 2017 Rockchip Electronics Co., Ltd
* Author: Andy Yan <andy.yan@rock-chips.com>
+ * (C) Copyright 2017 Theobroma Systems Design und Consulting GmbH
* SPDX-License-Identifier: GPL-2.0
*/

@@ -74,7 +75,7 @@ static uint32_t rkclk_pll_get_rate(struct rk3368_cru *cru,
}

static int rkclk_set_pll(struct rk3368_cru *cru, enum rk3368_pll_id pll_id,
- const struct pll_div *div, bool has_bwadj)
+ const struct pll_div *div)
{
struct rk3368_pll *pll = &cru->pll[pll_id];
/* All PLLs have same VCO and output frequency range restrictions*/
@@ -92,6 +93,12 @@ static int rkclk_set_pll(struct rk3368_cru *cru, enum rk3368_pll_id pll_id,
((div->nr - 1) << PLL_NR_SHIFT) |
((div->no - 1) << PLL_OD_SHIFT));
writel((div->nf - 1) << PLL_NF_SHIFT, &pll->con1);
+ /*
+ * BWADJ should be set to NF / 2 to ensure the nominal bandwidth.
+ * Compare the RK3368 TRM, section "3.6.4 PLL Bandwidth Adjustment".
+ */
+ clrsetbits_le32(&pll->con2, PLL_BWADJ_MASK, (div->nf >> 1) - 1);
+
udelay(10);

/* return from reset */
@@ -111,10 +118,10 @@ static void rkclk_init(struct rk3368_cru *cru)
{
u32 apllb, aplll, dpll, cpll, gpll;

- rkclk_set_pll(cru, APLLB, &apll_b_init_cfg, false);
- rkclk_set_pll(cru, APLLL, &apll_l_init_cfg, false);
- rkclk_set_pll(cru, GPLL, &gpll_init_cfg, false);
- rkclk_set_pll(cru, CPLL, &cpll_init_cfg, false);
+ rkclk_set_pll(cru, APLLB, &apll_b_init_cfg);
+ rkclk_set_pll(cru, APLLL, &apll_l_init_cfg);
+ rkclk_set_pll(cru, GPLL, &gpll_init_cfg);
+ rkclk_set_pll(cru, CPLL, &cpll_init_cfg);

apllb = rkclk_pll_get_rate(cru, APLLB);
aplll = rkclk_pll_get_rate(cru, APLLL);
--
2.1.4