[PATCH v2 4/6] clk: actions: Fix AHPPREDIV-H-AHB clock chain on Owl S500 SoC

From: Cristian Ciocaltea
Date: Thu May 27 2021 - 09:17:01 EST


There are a few issues with the setup of the Actions Semi Owl S500 SoC's
clock chain involving AHPPREDIV, H and AHB clocks:

* AHBPREDIV clock is defined as a muxer only, although it also acts as
a divider.
* H clock is using a wrong divider register offset
* AHB is defined as a multi-rate factor clock, but it is actually just
a fixed pass clock.

Let's provide the following fixes:

* Change AHBPREDIV clock to an ungated OWL_COMP_DIV definition.
* Use the correct register shift value in the OWL_DIVIDER definition
for H clock
* Drop the unneeded 'ahb_factor_table[]' and change AHB clock to an
ungated OWL_COMP_FIXED_FACTOR definition.

Fixes: ed6b4795ece4 ("clk: actions: Add clock driver for S500 SoC")
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@xxxxxxxxx>
---
Changes in v2:
- Reverted the addition of the clock div table for H clock to support the
'1' divider (according to the datasheet), even though the vendor
implementation marks it as reserved

drivers/clk/actions/owl-s500.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/clk/actions/owl-s500.c b/drivers/clk/actions/owl-s500.c
index 42d6899755e6..257923bd5386 100644
--- a/drivers/clk/actions/owl-s500.c
+++ b/drivers/clk/actions/owl-s500.c
@@ -153,11 +153,6 @@ static struct clk_factor_table hde_factor_table[] = {
{ 0, 0, 0 },
};

-static struct clk_factor_table ahb_factor_table[] = {
- { 1, 1, 2 }, { 2, 1, 3 },
- { 0, 0, 0 },
-};
-
static struct clk_div_table rmii_ref_div_table[] = {
{ 0, 4 }, { 1, 10 },
{ 0, 0 },
@@ -186,7 +181,6 @@ static struct clk_div_table nand_div_table[] = {

/* mux clock */
static OWL_MUX(dev_clk, "dev_clk", dev_clk_mux_p, CMU_DEVPLL, 12, 1, CLK_SET_RATE_PARENT);
-static OWL_MUX(ahbprediv_clk, "ahbprediv_clk", ahbprediv_clk_mux_p, CMU_BUSCLK1, 8, 3, CLK_SET_RATE_PARENT);

/* gate clocks */
static OWL_GATE(gpio_clk, "gpio_clk", "apb_clk", CMU_DEVCLKEN0, 18, 0, 0);
@@ -199,16 +193,25 @@ static OWL_GATE(timer_clk, "timer_clk", "hosc", CMU_DEVCLKEN1, 27, 0, 0);
static OWL_GATE(hdmi_clk, "hdmi_clk", "hosc", CMU_DEVCLKEN1, 3, 0, 0);

/* divider clocks */
-static OWL_DIVIDER(h_clk, "h_clk", "ahbprediv_clk", CMU_BUSCLK1, 12, 2, NULL, 0, 0);
+static OWL_DIVIDER(h_clk, "h_clk", "ahbprediv_clk", CMU_BUSCLK1, 2, 2, NULL, 0, 0);
static OWL_DIVIDER(apb_clk, "apb_clk", "ahb_clk", CMU_BUSCLK1, 14, 2, NULL, 0, 0);
static OWL_DIVIDER(rmii_ref_clk, "rmii_ref_clk", "ethernet_pll_clk", CMU_ETHERNETPLL, 1, 1, rmii_ref_div_table, 0, 0);

/* factor clocks */
-static OWL_FACTOR(ahb_clk, "ahb_clk", "h_clk", CMU_BUSCLK1, 2, 2, ahb_factor_table, 0, 0);
static OWL_FACTOR(de1_clk, "de_clk1", "de_clk", CMU_DECLK, 0, 4, de_factor_table, 0, 0);
static OWL_FACTOR(de2_clk, "de_clk2", "de_clk", CMU_DECLK, 4, 4, de_factor_table, 0, 0);

/* composite clocks */
+static OWL_COMP_DIV(ahbprediv_clk, "ahbprediv_clk", ahbprediv_clk_mux_p,
+ OWL_MUX_HW(CMU_BUSCLK1, 8, 3),
+ { 0 },
+ OWL_DIVIDER_HW(CMU_BUSCLK1, 12, 2, 0, NULL),
+ 0);
+
+static OWL_COMP_FIXED_FACTOR(ahb_clk, "ahb_clk", "h_clk",
+ { 0 },
+ 1, 1, CLK_SET_RATE_PARENT);
+
static OWL_COMP_FACTOR(vce_clk, "vce_clk", hde_clk_mux_p,
OWL_MUX_HW(CMU_VCECLK, 4, 2),
OWL_GATE_HW(CMU_DEVCLKEN0, 26, 0),
--
2.31.1