2019-05-20 11:42:53

by Nicolas Saenz Julienne

Subject: [RFC v2 1/5] clk: bcm2835: set CLK_GET_RATE_NOCACHE on CPU clocks

Raspberry Pi's firmware is responsible for updating the cpu clocks and
pll. This makes sure we get the right rates anytime.

Signed-off-by: Nicolas Saenz Julienne <[email protected]>
---
drivers/clk/bcm/clk-bcm2835.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index 770bb01f523e..c2772dfb155a 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -411,6 +411,7 @@ struct bcm2835_pll_data {
u32 reference_enable_mask;
/* Bit in CM_LOCK to indicate when the PLL has locked. */
u32 lock_mask;
+ u32 flags;

const struct bcm2835_pll_ana_bits *ana;

@@ -1299,7 +1300,7 @@ static struct clk_hw *bcm2835_register_pll(struct bcm2835_cprman *cprman,
init.num_parents = 1;
init.name = data->name;
init.ops = &bcm2835_pll_clk_ops;
- init.flags = CLK_IGNORE_UNUSED;
+ init.flags = data->flags | CLK_IGNORE_UNUSED;

pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
@@ -1660,6 +1661,7 @@ static const struct bcm2835_clk_desc clk_desc_array[] = {
.ana_reg_base = A2W_PLLB_ANA0,
.reference_enable_mask = A2W_XOSC_CTRL_PLLB_ENABLE,
.lock_mask = CM_LOCK_FLOCKB,
+ .flags = CLK_GET_RATE_NOCACHE,

.ana = &bcm2835_ana_default,

@@ -1674,7 +1676,7 @@ static const struct bcm2835_clk_desc clk_desc_array[] = {
.load_mask = CM_PLLB_LOADARM,
.hold_mask = CM_PLLB_HOLDARM,
.fixed_divider = 1,
- .flags = CLK_SET_RATE_PARENT),
+ .flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE),

/*
* PLLC is the core PLL, used to drive the core VPU clock.
--
2.21.0

2019-05-20 14:04:27

by Stefan Wahren

Subject: Re: [RFC v2 1/5] clk: bcm2835: set CLK_GET_RATE_NOCACHE on CPU clocks

On 20.05.19 12:47, Nicolas Saenz Julienne wrote:
> Raspberry Pi's firmware is responsible for updating the cpu clocks and
> pll. This makes sure we get the right rates anytime.
>
> Signed-off-by: Nicolas Saenz Julienne <[email protected]>
Acked-by: Stefan Wahren <[email protected]>