interconnect: qcom: qcm2290: Update EBI channel configuration
authorKonrad Dybcio <konrad.dybcio@linaro.org>
Fri, 25 Aug 2023 15:38:29 +0000 (17:38 +0200)
committerGeorgi Djakov <djakov@kernel.org>
Mon, 9 Oct 2023 12:08:20 +0000 (15:08 +0300)
commit550064a85ba564cfb508a995f45e39a6ad0e26ed
tree1e20907d4f8bca00e0ff545a1324cc7b9ea34dbd
parent8657ed471196f4dc8e7917453a39363e0014840c
interconnect: qcom: qcm2290: Update EBI channel configuration

QCM2290 can support two memory configurations: single-channel, 32-bit
wide LPDDR3 @ up to 933MHz (bus clock) or dual-channel, 16-bit wide
LPDDR4X @ up to 1804 MHz. The interconnect driver in its current form
seems to gravitate towards the first one, however there are no LPDDR3-
equipped boards upstream and we still don't have a great way to discern
the DDR generations on the kernel side.

To make DDR scaling possible on the only currently-supported 2290
board, stick with the LPDDR4X config by default. The side effect on any
potential LPDDR3 board would be that the requested bus clock rate is
too high (but still capped to the firmware-configured FMAX).

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230726-topic-icc_coeff-v4-7-c04b60caa467@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
drivers/interconnect/qcom/qcm2290.c