On 11/10/2017 10:09 AM, Simon Horman wrote:
> On Wed, Nov 08, 2017 at 10:28:06AM +0100, Marek Vasut wrote:
>> From: Kazufumi Ikeda <kaz-ikeda@xxxxxxxxxxxxx>
>>
>> This adds the suspend/resume supports for pcie-rcar. The resume handler
>> reprogram the hardware based on the software state kept in specific
>> device structures. Also it doesn't need to save any registers.
>>
>> Signed-off-by: Kazufumi Ikeda <kaz-ikeda@xxxxxxxxxxxxx>
>> Signed-off-by: Gaku Inami <gaku.inami.xw@xxxxxxxxxxxxxx>
>> Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxx>
>> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>> Cc: Simon Horman <horms+renesas@xxxxxxxxxxxx>
>> Cc: Wolfram Sang <wsa@xxxxxxxxxxxxx>
>> Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
>> ---
>> drivers/pci/host/pcie-rcar.c | 86 +++++++++++++++++++++++++++++++++++++++-----
>> 1 file changed, 78 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c
>> index 2b28292de93a..7a9e30185c79 100644
>> --- a/drivers/pci/host/pcie-rcar.c
>> +++ b/drivers/pci/host/pcie-rcar.c
>> @@ -471,6 +471,36 @@ static void rcar_pcie_force_speedup(struct rcar_pcie *pcie)
>> (macsr & LINK_SPEED) == LINK_SPEED_5_0GTS ? "5" : "2.5");
>> }
>>
>> +static int rcar_pcie_hw_enable(struct rcar_pcie *pcie)
>
> This function always returns 0 and the value is not checked by the caller.
> Can we change the return type to void?
Yes, done
>> +{
>> + struct resource_entry *win;
>> + LIST_HEAD(res);
>> + int i = 0;
>> +
>> + /* Try setting 5 GT/s link speed */
>
> What if it fails?
If it fails, we're back at 2.5 GT/s . The rcar_pcie_force_speedup()
first checks if the PCIe IP can do 5 GT/s at all. Only if so, tries to
initiate transition to 5 GT/s operation , checks whether that succeeded
and if it failed, falls back to 2.5 GT/s .
>> + rcar_pcie_force_speedup(pcie);
>> +
>> + /* Setup PCI resources */
>> + resource_list_for_each_entry(win, &pcie->resources) {
>> + struct resource *res = win->res;
>> +
>> + if (!res->flags)
>> + continue;
>> +
>> + switch (resource_type(res)) {
>> + case IORESOURCE_IO:
>> + case IORESOURCE_MEM:
>> + rcar_pcie_setup_window(i, pcie, res);
>> + i++;
>> + break;
>> + default:
>> + continue;
>
> Can the default case be omitted?
Sure
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> static int rcar_pcie_enable(struct rcar_pcie *pcie)
>> {
>> struct device *dev = pcie->dev;
>> @@ -872,11 +902,25 @@ static const struct irq_domain_ops msi_domain_ops = {
>> .map = rcar_msi_map,
>> };
>>
>> +static void rcar_pcie_hw_enable_msi(struct rcar_pcie *pcie)
>> +{
>> + struct rcar_msi *msi = &pcie->msi;
>> + unsigned long base;
>> +
>> + /* setup MSI data target */
>> + base = virt_to_phys((void *)msi->pages);
>
> Why do you need to cast to void *?
> I expect such casting can be done implicitly.
Because __get_free_pages() returns unsigned long and that's what's used
to assign msi->pages . And virt_to_phys() expects void * instead, thus
the cast.
>> +
>> + rcar_pci_write_reg(pcie, base | MSIFE, PCIEMSIALR);
>> + rcar_pci_write_reg(pcie, 0, PCIEMSIAUR);
>> +
>> + /* enable all MSI interrupts */
>> + rcar_pci_write_reg(pcie, 0xffffffff, PCIEMSIIER);
>> +}
>> +
>> static int rcar_pcie_enable_msi(struct rcar_pcie *pcie)
>> {
>> struct device *dev = pcie->dev;
>> struct rcar_msi *msi = &pcie->msi;
>> - unsigned long base;
>> int err, i;
>>
>> mutex_init(&msi->lock);
>> @@ -915,13 +959,7 @@ static int rcar_pcie_enable_msi(struct rcar_pcie *pcie)
>>
>> /* setup MSI data target */
>> msi->pages = __get_free_pages(GFP_KERNEL, 0);
>> - base = virt_to_phys((void *)msi->pages);
>> -
>> - rcar_pci_write_reg(pcie, base | MSIFE, PCIEMSIALR);
>> - rcar_pci_write_reg(pcie, 0, PCIEMSIAUR);
>> -
>> - /* enable all MSI interrupts */
>> - rcar_pci_write_reg(pcie, 0xffffffff, PCIEMSIIER);
>> + rcar_pcie_hw_enable_msi(pcie);
>>
>> return 0;
>>
>> @@ -1202,6 +1240,37 @@ static int rcar_pcie_probe(struct platform_device *pdev)
>> return err;
>> }
>>
>> +static int rcar_pcie_resume(struct device *dev)
>> +{
>> + struct rcar_pcie *pcie = dev_get_drvdata(dev);
>> + unsigned int data;
>> + int err;
>> + int (*hw_init_fn)(struct rcar_pcie *);
>
> Please sort local variables in reverse xmas tree order.
OK
>> +
>> + err = rcar_pcie_parse_map_dma_ranges(pcie, dev->of_node);
>> + if (err)
>> + return 0;
>> +
>> + /* Failure to get a link might just be that no cards are inserted */
>> + hw_init_fn = of_device_get_match_data(dev);
>> + err = hw_init_fn(pcie);
>> + if (err) {
>> + dev_info(dev, "PCIe link down\n");
>> + return 0;
>> + }
>> +
>> + data = rcar_pci_read_reg(pcie, MACSR);
>> + dev_info(dev, "PCIe x%d: link up\n", (data >> 20) & 0x3f);
>> +
>> + /* Enable MSI */
>> + if (IS_ENABLED(CONFIG_PCI_MSI))
>> + rcar_pcie_hw_enable_msi(pcie);
>> +
>> + rcar_pcie_hw_enable(pcie);
>> +
>> + return 0;
>> +}
>> +
>> static int rcar_pcie_resume_noirq(struct device *dev)
>> {
>> struct rcar_pcie *pcie = dev_get_drvdata(dev);
>> @@ -1218,6 +1287,7 @@ static int rcar_pcie_resume_noirq(struct device *dev)
>> }
>>
>> static const struct dev_pm_ops rcar_pcie_pm_ops = {
>> + SET_SYSTEM_SLEEP_PM_OPS(NULL, rcar_pcie_resume)
>> .resume_noirq = rcar_pcie_resume_noirq,
>> };
>>
>> --
>> 2.11.0
>>
--
Best regards,
Marek Vasut
