Re: [RFC 04/10] memory: Add Tegra124 memory controller support

[Joseph Lo <josephl-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>]

Hi Thierry,

On 06/27/2014 04:49 AM, Thierry Reding wrote:
[snip]
> +
> +#define MC_INTSTATUS 0x000
> +#define  MC_INT_DECERR_MTS (1 << 16)
> +#define  MC_INT_SECERR_SEC (1 << 13)
> +#define  MC_INT_DECERR_VPR (1 << 12)
> +#define  MC_INT_INVALID_APB_ASID_UPDATE (1 << 11)
> +#define  MC_INT_INVALID_SMMU_PAGE (1 << 10)
> +#define  MC_INT_ARBITRATION_EMEM (1 << 9)
> +#define  MC_INT_SECURITY_VIOLATION (1 << 8)
> +#define  MC_INT_DECERR_EMEM (1 << 6)
> +#define MC_INTMASK 0x004
> +#define MC_ERR_STATUS 0x08
> +#define MC_ERR_ADR 0x0c
> +
[snip]
> +
> +#define SMMU_PDE_ATTR          (SMMU_PDE_READABLE | SMMU_PDE_WRITABLE | \
> +                                SMMU_PDE_NONSECURE)
> +#define SMMU_PTE_ATTR          (SMMU_PTE_READABLE | SMMU_PTE_WRITABLE | \
> +                                SMMU_PTE_NONSECURE)
> +
> +#define SMMU_PDE_VACANT(n)     (((n) << 10) | SMMU_PDE_ATTR)
> +#define SMMU_PTE_VACANT(n)     (((n) << 12) | SMMU_PTE_ATTR)

There is an ISR to catch the invalid SMMU translation. Do you want to 
modify the identity mapping with read/write attribute of the unused SMMU 
pages?

This can make sure we capture the invalid SMMU translation. And helps 
for driver to capture issues when using SMMU.

-joseph

> +static irqreturn_t tegra124_mc_irq(int irq, void *data)
> +{
> +       struct tegra_mc *mc = data;
> +       u32 value, status, mask;
> +
> +       /* mask all interrupts to avoid flooding */
> +       mask = mc_readl(mc, MC_INTMASK);
> +       mc_writel(mc, 0, MC_INTMASK);
> +
> +       status = mc_readl(mc, MC_INTSTATUS);
> +       mc_writel(mc, status, MC_INTSTATUS);
> +
> +       dev_dbg(mc->dev, "INTSTATUS: %08x\n", status);
> +
> +       if (status & MC_INT_DECERR_MTS)
> +               dev_dbg(mc->dev, "  DECERR_MTS\n");
> +
> +       if (status & MC_INT_SECERR_SEC)
> +               dev_dbg(mc->dev, "  SECERR_SEC\n");
> +
> +       if (status & MC_INT_DECERR_VPR)
> +               dev_dbg(mc->dev, "  DECERR_VPR\n");
> +
> +       if (status & MC_INT_INVALID_APB_ASID_UPDATE)
> +               dev_dbg(mc->dev, "  INVALID_APB_ASID_UPDATE\n");
> +
> +       if (status & MC_INT_INVALID_SMMU_PAGE)
> +               dev_dbg(mc->dev, "  INVALID_SMMU_PAGE\n");
> +
> +       if (status & MC_INT_ARBITRATION_EMEM)
> +               dev_dbg(mc->dev, "  ARBITRATION_EMEM\n");
> +
> +       if (status & MC_INT_SECURITY_VIOLATION)
> +               dev_dbg(mc->dev, "  SECURITY_VIOLATION\n");
> +
> +       if (status & MC_INT_DECERR_EMEM)
> +               dev_dbg(mc->dev, "  DECERR_EMEM\n");
> +
> +       value = mc_readl(mc, MC_ERR_STATUS);
> +
> +       dev_dbg(mc->dev, "ERR_STATUS: %08x\n", value);
> +       dev_dbg(mc->dev, "  type: %x\n", (value >> 28) & 0x7);
> +       dev_dbg(mc->dev, "  protection: %x\n", (value >> 25) & 0x7);
> +       dev_dbg(mc->dev, "  adr_hi: %x\n", (value >> 20) & 0x3);
> +       dev_dbg(mc->dev, "  swap: %x\n", (value >> 18) & 0x1);
> +       dev_dbg(mc->dev, "  security: %x\n", (value >> 17) & 0x1);
> +       dev_dbg(mc->dev, "  r/w: %x\n", (value >> 16) & 0x1);
> +       dev_dbg(mc->dev, "  adr1: %x\n", (value >> 12) & 0x7);
> +       dev_dbg(mc->dev, "  client: %x\n", value & 0x7f);
> +
> +       value = mc_readl(mc, MC_ERR_ADR);
> +       dev_dbg(mc->dev, "ERR_ADR: %08x\n", value);
> +
> +       mc_writel(mc, mask, MC_INTMASK);
> +
> +       return IRQ_HANDLED;
> +}
> +