From 0feea33d79825d05b5ede30947db4df34722b463 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Wed, 22 Jul 2020 15:01:20 -0700 Subject: soc: qcom-geni-se: Don't use relaxed writes when writing commands Writing the command is the final step in kicking off a transfer. Let's use writel() to ensure that any other memory accesses are done before the command kicks off. It's expected that this is mostly relevant if we're in DMA mode but since it doesn't appear to regress performance in a measurable way [1] even in PIO mode and it's easier to reason about then let's just always use it. NOTE: this patch came about due to code inspection. No actual problems were observed that this patch fixes. [1] Tested by timing "flashrom -p ec" on a Chromebook which stresses GENI SPI a lot. Reviewed-by: Mukesh Kumar Savaliya Reviewed-by: Akash Asthana Reviewed-by: Stephen Boyd Suggested-by: Stephen Boyd Signed-off-by: Douglas Anderson Link: https://lore.kernel.org/r/20200722150113.1.Ia50ab5cb8a6d3a73d302e6bdc25542d48ffd27f4@changeid Signed-off-by: Bjorn Andersson --- include/linux/qcom-geni-se.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/qcom-geni-se.h') diff --git a/include/linux/qcom-geni-se.h b/include/linux/qcom-geni-se.h index 8f385fbe5a0e..ae4a8a766b69 100644 --- a/include/linux/qcom-geni-se.h +++ b/include/linux/qcom-geni-se.h @@ -296,7 +296,7 @@ static inline void geni_se_setup_m_cmd(struct geni_se *se, u32 cmd, u32 params) u32 m_cmd; m_cmd = (cmd << M_OPCODE_SHFT) | (params & M_PARAMS_MSK); - writel_relaxed(m_cmd, se->base + SE_GENI_M_CMD0); + writel(m_cmd, se->base + SE_GENI_M_CMD0); } /** @@ -316,7 +316,7 @@ static inline void geni_se_setup_s_cmd(struct geni_se *se, u32 cmd, u32 params) s_cmd &= ~(S_OPCODE_MSK | S_PARAMS_MSK); s_cmd |= (cmd << S_OPCODE_SHFT); s_cmd |= (params & S_PARAMS_MSK); - writel_relaxed(s_cmd, se->base + SE_GENI_S_CMD0); + writel(s_cmd, se->base + SE_GENI_S_CMD0); } /** -- cgit