Re: [PATCH V3 1/2] iommu/arm-smmu-v3: Add support for ECMDQ register mode

[Leizhen (ThunderTown)]

On 2024/4/25 22:41, Tanmay Jagdale wrote:
> +static int arm_smmu_ecmdq_probe(struct arm_smmu_device *smmu)
> +{
> +	int ret, cpu;
> +	u32 i, nump, numq, gap;
> +	u32 reg, shift_increment;
> +	u64 offset;
> +	void __iomem *cp_regs, *cp_base;
> +
> +	/* IDR6 */
> +	reg = readl_relaxed(smmu->base + ARM_SMMU_IDR6);
> +	nump = 1 << FIELD_GET(IDR6_LOG2NUMP, reg);
> +	numq = 1 << FIELD_GET(IDR6_LOG2NUMQ, reg);
> +	smmu->nr_ecmdq = nump * numq;
> +	gap = ECMDQ_CP_RRESET_SIZE >> FIELD_GET(IDR6_LOG2NUMQ, reg);
> +
> +	cp_regs = ioremap(smmu->iobase + ARM_SMMU_ECMDQ_CP_BASE, PAGE_SIZE);
> +	if (!cp_regs)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < nump; i++) {
> +		u64 val, pre_addr = 0;

This is my mistake. The 'pre_addr' should be defined out of this 'for' loop. Or, you
can remove all 'pre_addr' related statements, commercially available chips that have
been tested cannot have such errors.

> +
> +		val = readq_relaxed(cp_regs + 32 * i);
> +		if (!(val & ECMDQ_CP_PRESET)) {
> +			iounmap(cp_regs);
> +			dev_err(smmu->dev, "ecmdq control page %u is memory mode\n", i);
> +			return -EFAULT;
> +		}
> +

                                                     <---------------------------------------------
> +		if (i && ((val & ECMDQ_CP_ADDR) != (pre_addr + ECMDQ_CP_RRESET_SIZE))) {           |
> +			iounmap(cp_regs);                                                          |
> +			dev_err(smmu->dev, "ecmdq_cp memory region is not contiguous\n");          |
> +			return -EFAULT;                                                            |
> +		}                                                                                  |
> +                                                                                                |
> +		pre_addr = val & ECMDQ_CP_ADDR;                                                    |
                                                      <--------------------------------------------   feel free remove these
> +	}

-- 
Regards,
  Zhen Lei