On 16/04/19 10:27 AM, Peng Fan wrote: > Hi Adrian, > >> >> On 16/04/19 9:48 AM, Peng Fan wrote: >>> On i.MX8MM, we are running Dual Linux OS, with 1st Linux using SD Card >>> as rootfs storage, 2nd Linux using eMMC as rootfs storage. We let the >>> the 1st linux configure power/clock for the 2nd Linux. >>> >>> When the 2nd Linux is booting into rootfs stage, we let the 1st Linux >>> to destroy the 2nd linux, then restart the 1st linux, we met SDHCI >>> dump as following, after we clear the pending interrupt and halt >>> CQCTL, issue gone. >> >> I think it is better if the vendor driver does any necessary resets before >> initialization. > > In drivers/mmc/host/sdhci-esdhc-imx.c, there is a call to cqhci_init > " 1525 err = cqhci_init(cq_host, host->mmc, false);" > > You mean I put the following piece code into sdhci-esdhc-imx.c? > > " > status = cqhci_readl(cq_host, CQHCI_IS); > cqhci_writel(cq_host, status, CQHCI_IS); > cqhci_writel(cq_host, CQHCI_HALT, CQHCI_CTL); > " > > How about the following patch? > > diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c > index b8e11a77e274..f2e46ddf9695 100644 > --- a/drivers/mmc/host/sdhci-esdhc-imx.c > +++ b/drivers/mmc/host/sdhci-esdhc-imx.c > @@ -1435,6 +1435,7 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) > struct cqhci_host *cq_host; > int err; > struct pltfm_imx_data *imx_data; > + u32 status; > > host = sdhci_pltfm_init(pdev, &sdhci_esdhc_imx_pdata, > sizeof(*imx_data)); > @@ -1542,6 +1543,11 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) > err = cqhci_init(cq_host, host->mmc, false); > if (err) > goto disable_ahb_clk; > + > + status = cqhci_readl(cq_host, CQHCI_IS); > + cqhci_writel(cq_host, status, CQHCI_IS); > + cqhci_writel(cq_host, CQHCI_HALT, CQHCI_CTL); > + > } > It would be nicer to: 1. Define how CQHCI gets reset. For example, with our controllers SDHCI_RESET_ALL also resets CQHCI. 2. Define when CQHCI should be reset. e.g. using the ->reset() host op for example. 3. Implement a patch that meets those requirements.
