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Subject[PATCH 1/2] clk: bcm2835: Fix setting of PLL divider clock rates
Date
Our dividers weren't being set successfully because CM_PASSWORD wasn't
included in the register write. It looks easier to just compute the
divider to write ourselves than to update clk-divider for the ability
to OR in some arbitrary bits on write.

Fixes about half of the video modes on my HDMI monitor (everything
except 720x400).

Cc: stable@vger.kernel.org
Signed-off-by: Eric Anholt <eric@anholt.net>
---
drivers/clk/bcm/clk-bcm2835.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index 015e687..9f4df8f 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -1107,13 +1107,15 @@ static int bcm2835_pll_divider_set_rate(struct clk_hw *hw,
struct bcm2835_pll_divider *divider = bcm2835_pll_divider_from_hw(hw);
struct bcm2835_cprman *cprman = divider->cprman;
const struct bcm2835_pll_divider_data *data = divider->data;
- u32 cm;
- int ret;
+ u32 cm, div, max_div = 1 << A2W_PLL_DIV_BITS;

- ret = clk_divider_ops.set_rate(hw, rate, parent_rate);
- if (ret)
- return ret;
+ div = DIV_ROUND_UP_ULL(parent_rate, rate);
+
+ div = min(div, max_div);
+ if (div == max_div)
+ div = 0;

+ cprman_write(cprman, data->a2w_reg, div);
cm = cprman_read(cprman, data->cm_reg);
cprman_write(cprman, data->cm_reg, cm | data->load_mask);
cprman_write(cprman, data->cm_reg, cm & ~data->load_mask);
--
2.7.0
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