2021-06-17 05:19:43

by Gabriel FERNANDEZ

Subject: [RESEND PATCH v3 02/11] clk: stm32mp1: merge 'ck_hse_rtc' and 'ck_rtc' into one clock

From: Gabriel Fernandez <[email protected]>

'ck_rtc' has multiple clocks as input (ck_hsi, ck_lsi, and ck_hse).
A divider is available only on the specific rtc input for ck_hse.
This Merge will facilitate to have a more coherent clock tree
in no trusted / trusted world.

Signed-off-by: Gabriel Fernandez <[email protected]>
---
drivers/clk/clk-stm32mp1.c | 54 +++++++++++++++++++++++++++++++++-----
1 file changed, 48 insertions(+), 6 deletions(-)

diff --git a/drivers/clk/clk-stm32mp1.c b/drivers/clk/clk-stm32mp1.c
index 35d5aee8f9b0..a7c244fd0b03 100644
--- a/drivers/clk/clk-stm32mp1.c
+++ b/drivers/clk/clk-stm32mp1.c
@@ -245,7 +245,7 @@ static const char * const dsi_src[] = {
};

static const char * const rtc_src[] = {
- "off", "ck_lse", "ck_lsi", "ck_hse_rtc"
+ "off", "ck_lse", "ck_lsi", "ck_hse"
};

static const char * const mco1_src[] = {
@@ -1031,6 +1031,47 @@ static struct clk_hw *clk_register_cktim(struct device *dev, const char *name,
return hw;
}

+/* The divider of RTC clock concerns only ck_hse clock */
+#define HSE_RTC 3
+
+static unsigned long clk_divider_rtc_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ if (clk_hw_get_parent(hw) == clk_hw_get_parent_by_index(hw, HSE_RTC))
+ return clk_divider_ops.recalc_rate(hw, parent_rate);
+
+ return parent_rate;
+}
+
+static int clk_divider_rtc_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ if (clk_hw_get_parent(hw) == clk_hw_get_parent_by_index(hw, HSE_RTC))
+ return clk_divider_ops.set_rate(hw, rate, parent_rate);
+
+ return parent_rate;
+}
+
+static int clk_divider_rtc_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
+{
+ unsigned long best_parent_rate = req->best_parent_rate;
+
+ if (req->best_parent_hw == clk_hw_get_parent_by_index(hw, HSE_RTC)) {
+ req->rate = clk_divider_ops.round_rate(hw, req->rate, &best_parent_rate);
+ req->best_parent_rate = best_parent_rate;
+ } else {
+ req->rate = best_parent_rate;
+ }
+
+ return 0;
+}
+
+static const struct clk_ops rtc_div_clk_ops = {
+ .recalc_rate = clk_divider_rtc_recalc_rate,
+ .set_rate = clk_divider_rtc_set_rate,
+ .determine_rate = clk_divider_rtc_determine_rate
+};
+
struct stm32_pll_cfg {
u32 offset;
};
@@ -1243,6 +1284,10 @@ _clk_stm32_register_composite(struct device *dev,
_STM32_DIV(_div_offset, _div_shift, _div_width,\
_div_flags, _div_table, NULL)\

+#define _DIV_RTC(_div_offset, _div_shift, _div_width, _div_flags, _div_table)\
+ _STM32_DIV(_div_offset, _div_shift, _div_width,\
+ _div_flags, _div_table, &rtc_div_clk_ops)
+
#define _STM32_MUX(_offset, _shift, _width, _mux_flags, _mmux, _ops)\
.mux = &(struct stm32_mux_cfg) {\
&(struct mux_cfg) {\
@@ -1965,13 +2010,10 @@ static const struct clock_config stm32mp1_clock_cfg[] = {
_DIV(RCC_ETHCKSELR, 4, 4, 0, NULL)),

/* RTC clock */
- DIV(NO_ID, "ck_hse_rtc", "ck_hse", 0, RCC_RTCDIVR, 0, 6, 0),
-
- COMPOSITE(RTC, "ck_rtc", rtc_src, CLK_OPS_PARENT_ENABLE |
- CLK_SET_RATE_PARENT,
+ COMPOSITE(RTC, "ck_rtc", rtc_src, CLK_OPS_PARENT_ENABLE,
_GATE(RCC_BDCR, 20, 0),
_MUX(RCC_BDCR, 16, 2, 0),
- _NO_DIV),
+ _DIV_RTC(RCC_RTCDIVR, 0, 6, 0, NULL)),

/* MCO clocks */
COMPOSITE(CK_MCO1, "ck_mco1", mco1_src, CLK_OPS_PARENT_ENABLE |
--
2.17.1

2021-06-28 01:35:53

by Stephen Boyd

Subject: Re: [RESEND PATCH v3 02/11] clk: stm32mp1: merge 'ck_hse_rtc' and 'ck_rtc' into one clock

Quoting [email protected] (2021-06-16 22:18:05)
> From: Gabriel Fernandez <[email protected]>
>
> 'ck_rtc' has multiple clocks as input (ck_hsi, ck_lsi, and ck_hse).
> A divider is available only on the specific rtc input for ck_hse.
> This Merge will facilitate to have a more coherent clock tree
> in no trusted / trusted world.
>
> Signed-off-by: Gabriel Fernandez <[email protected]>
> ---

Applied to clk-next