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Subject[PATCH V2 1/8] memory: emif: Fix the lpmode timeout calculation
Date
The driver tries to round up the specified timeout cycles to
the next power of 2 value. This should be done defore updating
timeout variable.
Correcting this here.

Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
---
Changes since V1:
Updated Changelog and $subject
Added a comment describing timeout calculation.

drivers/memory/emif.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
index df08736..508763c 100644
--- a/drivers/memory/emif.c
+++ b/drivers/memory/emif.c
@@ -728,13 +728,17 @@ static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
/* Timeout based on DDR frequency */
timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;

- /* The value to be set in register is "log2(timeout) - 3" */
+ /*
+ * The value to be set in register is "log2(timeout) - 3"
+ * if timeout < 16 load 0 in register
+ * if timeout is not a power of 2, round to next highest power of 2
+ */
if (timeout < 16) {
timeout = 0;
} else {
- timeout = __fls(timeout) - 3;
if (timeout & (timeout - 1))
- timeout++;
+ timeout <<= 1;
+ timeout = __fls(timeout) - 3;
}

switch (lpmode) {
--
1.7.9.5


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