linux-kernel - [PATCH v4 07/10] interconnect: qcom: qcm2290: Update EBI channel configuration

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20230726-topic-icc_coeff-v4-7-c04b60caa467@linaro.org>
Date:   Fri, 25 Aug 2023 17:38:29 +0200
From:   Konrad Dybcio <konrad.dybcio@...aro.org>
To:     Andy Gross <agross@...nel.org>,
        Bjorn Andersson <andersson@...nel.org>,
        Georgi Djakov <djakov@...nel.org>,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>
Cc:     Marijn Suijten <marijn.suijten@...ainline.org>,
        linux-arm-msm@...r.kernel.org, linux-pm@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-clk@...r.kernel.org,
        Konrad Dybcio <konrad.dybcio@...aro.org>
Subject: [PATCH v4 07/10] 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@...aro.org>
---
 drivers/interconnect/qcom/qcm2290.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/interconnect/qcom/qcm2290.c b/drivers/interconnect/qcom/qcm2290.c
index 7abc0c449220..b88cf9a022e0 100644
--- a/drivers/interconnect/qcom/qcm2290.c
+++ b/drivers/interconnect/qcom/qcm2290.c
@@ -678,7 +678,8 @@ static struct qcom_icc_node mas_gfx3d = {
 static struct qcom_icc_node slv_ebi1 = {
 	.name = "slv_ebi1",
 	.id = QCM2290_SLAVE_EBI1,
-	.buswidth = 8,
+	.buswidth = 4,
+	.channels = 2,
 	.mas_rpm_id = -1,
 	.slv_rpm_id = 0,
 };

-- 
2.42.0