Douglas Anderson 614199a8d1 soc: qcom: geni: More properly switch to DMA mode ... [ Upstream commit 4b6ea87be44ef34732846fc71e44c41125f0c4fa ] On geni-i2c transfers using DMA, it was seen that if you program the command (I2C_READ) before calling geni_se_rx_dma_prep() that it could cause interrupts to fire. If we get unlucky, these interrupts can just keep firing (and not be handled) blocking further progress and hanging the system. In commit 02b9aec592 ("i2c: i2c-qcom-geni: Fix DMA transfer race") we avoided that by making sure we didn't program the command until after geni_se_rx_dma_prep() was called. While that avoided the problems, it also turns out to be invalid. At least in the TX case we started seeing sporadic corrupted transfers. This is easily seen by adding an msleep() between the DMA prep and the writing of the command, which makes the problem worse. That means we need to revert that commit and find another way to fix the bogus IRQs. Specifically, after reverting commit 02b9aec592 ("i2c: i2c-qcom-geni: Fix DMA transfer race"), I put some traces in. I found that the when the interrupts were firing like crazy: - "m_stat" had bits for M_RX_IRQ_EN, M_RX_FIFO_WATERMARK_EN set. - "dma" was set. Further debugging showed that I could make the problem happen more reliably by adding an "msleep(1)" any time after geni_se_setup_m_cmd() ran up until geni_se_rx_dma_prep() programmed the length. A rather simple fix is to change geni_se_select_dma_mode() so it's a true inverse of geni_se_select_fifo_mode() and disables all the FIFO related interrupts. Now the problematic interrupts can't fire and we can program things in the correct order without worrying. As part of this, let's also change the writel_relaxed() in the prepare function to a writel() so that our DMA is guaranteed to be prepared now that we can't rely on geni_se_setup_m_cmd()'s writel(). NOTE: the only current user of GENI_SE_DMA in mainline is i2c. Fixes: 37692de5d5 ("i2c: i2c-qcom-geni: Add bus driver for the Qualcomm GENI I2C controller") Fixes: 02b9aec592 ("i2c: i2c-qcom-geni: Fix DMA transfer race") Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Akash Asthana <akashast@codeaurora.org> Tested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Link: https://lore.kernel.org/r/20201013142448.v2.1.Ifdb1b69fa3367b81118e16e9e4e63299980ca798@changeid Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-12-30 11:52:57 +01:00
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actions	soc: actions: include header to fix missing prototype	2020-09-22 12:45:16 +05:30
amlogic	soc: amlogic: pm-domains: use always-on flag	2020-09-24 09:50:01 -07:00
aspeed
atmel
bcm	soc: bcm: brcmstb: biuctrl: Change RAC data line prefetching after 4 consecutive lines	2020-09-06 12:43:02 -07:00
dove
fsl	soc: fsl: dpio: Get the cpumask through cpumask_of(cpu)	2020-11-23 19:27:45 -06:00
gemini
imx	soc: imx: gpcv2: Use dev_err_probe() to simplify error handling	2020-08-22 20:57:57 +08:00
ixp4xx
kendryte
lantiq
mediatek	soc: mediatek: Check if power domains can be powered on at boot time	2020-12-30 11:52:56 +01:00
qcom	soc: qcom: geni: More properly switch to DMA mode	2020-12-30 11:52:57 +01:00
renesas	soc: renesas: rmobile-sysc: Fix some leaks in rmobile_init_pm_domains()	2020-12-30 11:52:56 +01:00
rockchip	PM: AVS: rockchip-io: Move the driver to the rockchip specific drivers	2020-10-16 18:23:15 +02:00
samsung	ARM: SoC platform updates	2020-10-24 10:33:08 -07:00
sifive
sunxi	soc: sunxi: sram: remove unneeded semicolon	2020-09-11 17:02:39 +02:00
tegra	soc/tegra: fuse: Fix index bug in get_process_id	2020-12-26 16:02:38 +01:00
ti	soc: ti: ti_sci_pm_domains: check for proper args count in xlate	2020-10-29 22:13:38 +01:00
ux500	soc: ux500: Use custom soc attribute group instead of device_create_file	2020-07-06 09:48:06 +01:00
versatile	soc: integrator: Drop pointless static qualifier in integrator_soc_init()	2020-08-20 08:57:05 +02:00
xilinx	soc: xilinx: Fix error code in zynqmp_pm_probe()	2020-06-18 10:07:17 +02:00
zte
Kconfig
Makefile