[PATCH v11 4/6] PCI: hisi: Add PCIe host support for HiSilicon SoC Hip05

Bjorn Helgaas helgaas at kernel.org
Thu Oct 22 11:46:22 PDT 2015

Hi Zhou,

This looks pretty good to me; just a mask question and add a printk.

On Fri, Oct 16, 2015 at 06:23:39PM +0800, Zhou Wang wrote:
> This patch adds PCIe host support for HiSilicon SoC Hip05.
> ...

> +#define PCIE_SUBCTRL_SYS_STATE4_REG                     0x6818
> +#define PCIE_LTSSM_LINKUP_STATE                         0x11
> +#define PCIE_LTSSM_STATE_MASK                           0x3F

Fabio unified some of this; see

So the question is, why do you use a 6-bit (0x3f) LTSSM_STATE_MASK?
We think we can use a 5-bit mask (0x1f) for all the other
DesignWare-based systems.

> +/* Hip05 PCIe host only supports 32-bit config access */

Thanks for the comment asserting that Hip05 only supports 32-bit
config access.  I assume you confirmed that with the hardware
designers.  As far as I can tell, this *is* a hardware defect, and at
the minimum, I want a printk at driver probe-time so a dmesg log will
have a clue that read/modify/write on config space might do the wrong

> +static int hisi_pcie_cfg_read(struct pcie_port *pp, int where, int size,
> +			      u32 *val)
> ...


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