lkml.org 
[lkml]   [2018]   [Feb]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v13 4/9] PCI: Apply the new generic I/O management on PCI IO hosts
On Wed, Feb 14, 2018 at 8:42 AM, John Garry <john.garry@huawei.com> wrote:
> On 13/02/2018 22:57, dann frazier wrote:
>>
>> On Wed, Feb 14, 2018 at 01:45:28AM +0800, John Garry wrote:
>>>
>>> From: Zhichang Yuan <yuanzhichang@hisilicon.com>
>>>
>>> After introducing the new generic I/O space management in logic pio, the
>>> original PCI MMIO relevant helpers need to be updated based on the new
>>> interfaces.
>>> This patch adapts the corresponding code to match the changes introduced
>>> by logic pio.
>>>
>>> Signed-off-by: Zhichang Yuan <yuanzhichang@hisilicon.com>
>>> Signed-off-by: Gabriele Paoloni <gabriele.paoloni@huawei.com>
>>> Signed-off-by: Arnd Bergmann <arnd@arndb.de> #earlier draft
>>> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
>>
>>
>> I saw that Bjorn Acked this back in v6, but it seems like the code in
>> pci.c was reworked a bit for v7 onwards and I didn't see a follow-up
>> review (apologies if I just missed it). In which case, maybe his Ack
>> should have the "#earlier draft" tag as well?
>>
>
> Hi Dann,
>
> I see Bjorn acked again later on in the series, here:
> https://lkml.org/lkml/2017/5/26/612

Yep, you're right, sorry for missing that :)

>
>>> ---
>>> drivers/pci/pci.c | 95
>>> +++++++++---------------------------------------
>>> include/asm-generic/io.h | 2 +-
>>> 2 files changed, 18 insertions(+), 79 deletions(-)
>>>
>>> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
>>> index 07290a3..8aa5c54 100644
>>> --- a/drivers/pci/pci.c
>>> +++ b/drivers/pci/pci.c
>>> @@ -22,6 +22,7 @@
>>> #include <linux/spinlock.h>
>>> #include <linux/string.h>
>>> #include <linux/log2.h>
>>> +#include <linux/logic_pio.h>
>>> #include <linux/pci-aspm.h>
>>> #include <linux/pm_wakeup.h>
>>> #include <linux/interrupt.h>
>>> @@ -3440,17 +3441,6 @@ int pci_request_regions_exclusive(struct pci_dev
>>> *pdev, const char *res_name)
>>> }
>>> EXPORT_SYMBOL(pci_request_regions_exclusive);
>>>
>>> -#ifdef PCI_IOBASE
>>> -struct io_range {
>>> - struct list_head list;
>>> - phys_addr_t start;
>>> - resource_size_t size;
>>> -};
>>> -
>>> -static LIST_HEAD(io_range_list);
>>> -static DEFINE_SPINLOCK(io_range_lock);
>>> -#endif
>>> -
>>> /*
>>> * Record the PCI IO range (expressed as CPU physical address + size).
>>> * Return a negative value if an error has occured, zero otherwise
>>> @@ -3458,51 +3448,28 @@ struct io_range {
>>> int pci_register_io_range(struct fwnode_handle *fwnode, phys_addr_t
>>> addr,
>>> resource_size_t size)
>>> {
>>> - int err = 0;
>>> -
>>> + int ret = 0;
>>> #ifdef PCI_IOBASE
>>> - struct io_range *range;
>>> - resource_size_t allocated_size = 0;
>>> -
>>> - /* check if the range hasn't been previously recorded */
>>> - spin_lock(&io_range_lock);
>>> - list_for_each_entry(range, &io_range_list, list) {
>>> - if (addr >= range->start && addr + size <= range->start +
>>> size) {
>>> - /* range already registered, bail out */
>>> - goto end_register;
>>> - }
>>> - allocated_size += range->size;
>>> - }
>>> + struct logic_pio_hwaddr *range;
>>>
>>> - /* range not registed yet, check for available space */
>>> - if (allocated_size + size - 1 > IO_SPACE_LIMIT) {
>>> - /* if it's too big check if 64K space can be reserved */
>>> - if (allocated_size + SZ_64K - 1 > IO_SPACE_LIMIT) {
>>> - err = -E2BIG;
>>> - goto end_register;
>>> - }
>>> -
>>> - size = SZ_64K;
>>> - pr_warn("Requested IO range too big, new size set to
>>> 64K\n");
>>> - }
>>> + if (!size || addr + size < addr)
>>> + return -EINVAL;
>>>
>>> - /* add the range to the list */
>>> range = kzalloc(sizeof(*range), GFP_ATOMIC);
>>> - if (!range) {
>>> - err = -ENOMEM;
>>> - goto end_register;
>>> - }
>>> + if (!range)
>>> + return -ENOMEM;
>>>
>>> - range->start = addr;
>>> + range->fwnode = fwnode;
>>> range->size = size;
>>> + range->hw_start = addr;
>>> + range->flags = PIO_CPU_MMIO;
>>>
>>> - list_add_tail(&range->list, &io_range_list);
>>> -
>>> -end_register:
>>> - spin_unlock(&io_range_lock);
>>> + ret = logic_pio_register_range(range);
>>> + if (ret)
>>> + kfree(range);
>>> #endif
>>>
>>> - return err;
>>> + return ret;
>>> }
>>>
>>> phys_addr_t pci_pio_to_address(unsigned long pio)
>>> @@ -3510,21 +3477,10 @@ phys_addr_t pci_pio_to_address(unsigned long pio)
>>> phys_addr_t address = (phys_addr_t)OF_BAD_ADDR;
>>>
>>> #ifdef PCI_IOBASE
>>> - struct io_range *range;
>>> - resource_size_t allocated_size = 0;
>>> -
>>> - if (pio > IO_SPACE_LIMIT)
>>> + if (pio >= MMIO_UPPER_LIMIT)
>>> return address;
>>>
>>> - spin_lock(&io_range_lock);
>>> - list_for_each_entry(range, &io_range_list, list) {
>>> - if (pio >= allocated_size && pio < allocated_size +
>>> range->size) {
>>> - address = range->start + pio - allocated_size;
>>> - break;
>>> - }
>>> - allocated_size += range->size;
>>> - }
>>> - spin_unlock(&io_range_lock);
>>> + address = logic_pio_to_hwaddr(pio);
>>> #endif
>>>
>>> return address;
>>> @@ -3533,25 +3489,8 @@ phys_addr_t pci_pio_to_address(unsigned long pio)
>>> unsigned long __weak pci_address_to_pio(phys_addr_t address)
>>> {
>>> #ifdef PCI_IOBASE
>>> - struct io_range *res;
>>> - resource_size_t offset = 0;
>>> - unsigned long addr = -1;
>>> -
>>> - spin_lock(&io_range_lock);
>>> - list_for_each_entry(res, &io_range_list, list) {
>>> - if (address >= res->start && address < res->start +
>>> res->size) {
>>> - addr = address - res->start + offset;
>>> - break;
>>> - }
>>> - offset += res->size;
>>> - }
>>> - spin_unlock(&io_range_lock);
>>> -
>>> - return addr;
>>> + return logic_pio_trans_cpuaddr(address);
>>> #else
>>> - if (address > IO_SPACE_LIMIT)
>>> - return (unsigned long)-1;
>>> -
>>
>>
>> Why is this check now safe to drop in the !PCI_IOBASE case?
>
>
> So I have been studying the (long) patchset history and I don't see the
> reason for removing this check, and I think it can be reinstated.
>
> The address and pio are analogous here, and pio should not exceed the IO
> space limit, so just a safety check.

Sounds good.

-dann

>>
>> -dann
>>
>>> return (unsigned long) address;
>>> #endif
>>> }
>>> diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
>>> index b7996a79..5a59931 100644
>>> --- a/include/asm-generic/io.h
>>> +++ b/include/asm-generic/io.h
>>> @@ -901,7 +901,7 @@ static inline void iounmap(void __iomem *addr)
>>> #define ioport_map ioport_map
>>> static inline void __iomem *ioport_map(unsigned long port, unsigned int
>>> nr)
>>> {
>
>
> Thanks,
> John
>
>>> - return PCI_IOBASE + (port & IO_SPACE_LIMIT);
>>> + return PCI_IOBASE + (port & MMIO_UPPER_LIMIT);
>>> }
>>> #endif
>>>
>>
>> .
>>
>
>

\
 
 \ /
  Last update: 2018-02-14 17:05    [W:0.066 / U:1.692 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site