Re: [dpdk-dev] [PATCH v5 2/3] PCI: support MMIO in rte_pci_ioport_map/unap/read/write

[Maxime Coquelin <maxime.coquelin@redhat.com>]

Title should be something like:

"bus/pci: support MMIO in PCI ioport accessors

On 10/22/20 5:51 PM, 谢华伟(此时此刻） wrote:
> From: "huawei.xhw" <huawei.xhw@alibaba-inc.com>
> 
> If IO BAR, we get PIO address.
> If MMIO BAR, we get mapped virtual address.
> We distinguish PIO and MMIO by their address like how kernel does.
> ioread/write8/16/32 is provided to access PIO/MMIO.
> BTW, for virtio on arch other than x86, BAR flag indicates PIO but is mapped.

No acronym in the commit message.
Also, I am not sure to understand this comment.
Does it means in the case of ARM for example, the IORESOURCE_IO flag is
set but the base address is above PIO_MAX?

> 
> Signed-off-by: huawei.xhw <huawei.xhw@alibaba-inc.com>

As in previous patch, we need your full name for the sign-off.

> ---
>  drivers/bus/pci/linux/pci.c     |   4 --
>  drivers/bus/pci/linux/pci_uio.c | 123 ++++++++++++++++++++++++++--------------
>  2 files changed, 82 insertions(+), 45 deletions(-)
> 
> diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c
> index 0f38abf..0dc99e9 100644
> --- a/drivers/bus/pci/linux/pci.c
> +++ b/drivers/bus/pci/linux/pci.c
> @@ -715,8 +715,6 @@ int rte_pci_write_config(const struct rte_pci_device *device,
>  		break;
>  #endif
>  	case RTE_PCI_KDRV_IGB_UIO:
> -		pci_uio_ioport_read(p, data, len, offset);
> -		break;

I think this part should be in patch 1.

>  	case RTE_PCI_KDRV_UIO_GENERIC:
>  		pci_uio_ioport_read(p, data, len, offset);
>  		break;
> @@ -736,8 +734,6 @@ int rte_pci_write_config(const struct rte_pci_device *device,
>  		break;
>  #endif
>  	case RTE_PCI_KDRV_IGB_UIO:
> -		pci_uio_ioport_write(p, data, len, offset);
> -		break;

Same here.

>  	case RTE_PCI_KDRV_UIO_GENERIC:
>  		pci_uio_ioport_write(p, data, len, offset);
>  		break;
> diff --git a/drivers/bus/pci/linux/pci_uio.c b/drivers/bus/pci/linux/pci_uio.c
> index 01f2a40..c19382f 100644
> --- a/drivers/bus/pci/linux/pci_uio.c
> +++ b/drivers/bus/pci/linux/pci_uio.c
> @@ -379,14 +379,9 @@
>  	char buf[BUFSIZ];
>  	uint64_t phys_addr, end_addr, flags;
>  	unsigned long base;
> +	bool iobar;
>  	int i;
>  
> -	if (rte_eal_iopl_init() != 0) {
> -		RTE_LOG(ERR, EAL, "%s(): insufficient ioport permissions for PCI device %s\n",
> -			__func__, dev->name);
> -		return -1;
> -	}
> -
>  	/* open and read addresses of the corresponding resource in sysfs */
>  	snprintf(filename, sizeof(filename), "%s/" PCI_PRI_FMT "/resource",
>  		rte_pci_get_sysfs_path(), dev->addr.domain, dev->addr.bus,
> @@ -408,15 +403,30 @@
>  		&end_addr, &flags) < 0)
>  		goto error;
>  
> -	if (!(flags & IORESOURCE_IO)) {
> -		RTE_LOG(ERR, EAL, "%s(): bar resource other than IO is not supported\n", __func__);
> +	if (flags & IORESOURCE_IO) {
> +		iobar = 1;
> +		base = (unsigned long)phys_addr;
> +		RTE_LOG(INFO, EAL, "%s(): PIO BAR %08lx detected\n", __func__, base);
> +	} else if (flags & IORESOURCE_MEM) {
> +		iobar = 0;
> +		base = (unsigned long)dev->mem_resource[bar].addr;
> +		RTE_LOG(INFO, EAL, "%s(): MMIO BAR %08lx detected\n", __func__, base);
> +	} else {
> +		RTE_LOG(ERR, EAL, "%s(): unknown BAR type\n", __func__);
> +		goto error;
> +	}
> +
> +
> +	if (iobar && rte_eal_iopl_init() != 0) {
> +		RTE_LOG(ERR, EAL, "%s(): insufficient ioport permissions for PCI device %s\n",
> +			__func__, dev->name);
>  		goto error;
>  	}
> -	base = (unsigned long)phys_addr;
> -	RTE_LOG(INFO, EAL, "%s(): PIO BAR %08lx detected\n", __func__, base);
>  
> -	if (base > UINT16_MAX)
> +	if (iobar && (base > UINT16_MAX)) {
> +		RTE_LOG(ERR, EAL, "%s(): %08lx too large PIO resource\n", __func__, base);
>  		goto error;
> +	}

It looks like above check could be moved directly to (flags &
IORESOURCE_IO) case, so iobar boolean is not needed.

>  
>  	/* FIXME only for primary process ? */
>  	if (dev->intr_handle.type == RTE_INTR_HANDLE_UNKNOWN) {
> @@ -517,6 +527,61 @@
>  }
>  #endif
>  
> +#define PIO_MAX 0x10000
> +static inline uint8_t ioread8(void *addr)
> +{
> +	uint8_t val;
> +
> +	val = (uint64_t)(uintptr_t)addr >= PIO_MAX ?
> +		*(volatile uint8_t *)addr :
> +		inb((unsigned long)addr);
> +
> +	return val;
> +}
> +
> +static inline uint16_t ioread16(void *addr)
> +{
> +	uint16_t val;
> +
> +	val = (uint64_t)(uintptr_t)addr >= PIO_MAX ?
> +		*(volatile uint16_t *)addr :
> +		inw((unsigned long)addr);
> +
> +	return val;
> +}
> +
> +static inline uint32_t ioread32(void *addr)
> +{
> +	uint32_t val;
> +
> +	val = (uint64_t)(uintptr_t)addr >= PIO_MAX ?
> +		*(volatile uint32_t *)addr :
> +		inl((unsigned long)addr);
> +
> +	return val;
> +}
> +
> +static inline void iowrite8(uint8_t val, void *addr)
> +{
> +	(uint64_t)(uintptr_t)addr >= PIO_MAX ?
> +		*(volatile uint8_t *)addr = val :
> +		outb(val, (unsigned long)addr);
> +}
> +
> +static inline void iowrite16(uint16_t val, void *addr)
> +{
> +	(uint64_t)(uintptr_t)addr >= PIO_MAX ?
> +		*(volatile uint16_t *)addr = val :
> +		outw(val, (unsigned long)addr);
> +}
> +
> +static inline void iowrite32(uint32_t val, void *addr)
> +{
> +	(uint64_t)(uintptr_t)addr >= PIO_MAX ?
> +		*(volatile uint32_t *)addr = val :
> +		outl(val, (unsigned long)addr);
> +}
> +
>  void
>  pci_uio_ioport_read(struct rte_pci_ioport *p,
>  		    void *data, size_t len, off_t offset)
> @@ -528,25 +593,13 @@
>  	for (d = data; len > 0; d += size, reg += size, len -= size) {
>  		if (len >= 4) {
>  			size = 4;
> -#if defined(RTE_ARCH_X86)
> -			*(uint32_t *)d = inl(reg);
> -#else
> -			*(uint32_t *)d = *(volatile uint32_t *)reg;
> -#endif
> +			*(uint32_t *)d = ioread32((void *)reg);
>  		} else if (len >= 2) {
>  			size = 2;
> -#if defined(RTE_ARCH_X86)
> -			*(uint16_t *)d = inw(reg);
> -#else
> -			*(uint16_t *)d = *(volatile uint16_t *)reg;
> -#endif
> +			*(uint16_t *)d = ioread16((void *)reg);
>  		} else {
>  			size = 1;
> -#if defined(RTE_ARCH_X86)
> -			*d = inb(reg);
> -#else
> -			*d = *(volatile uint8_t *)reg;
> -#endif
> +			*d = ioread8((void *)reg);
>  		}
>  	}
>  }
> @@ -562,25 +615,13 @@
>  	for (s = data; len > 0; s += size, reg += size, len -= size) {
>  		if (len >= 4) {
>  			size = 4;
> -#if defined(RTE_ARCH_X86)
> -			outl_p(*(const uint32_t *)s, reg);
> -#else
> -			*(volatile uint32_t *)reg = *(const uint32_t *)s;
> -#endif
> +			iowrite32(*(const uint32_t *)s, (void *)reg);
>  		} else if (len >= 2) {
>  			size = 2;
> -#if defined(RTE_ARCH_X86)
> -			outw_p(*(const uint16_t *)s, reg);
> -#else
> -			*(volatile uint16_t *)reg = *(const uint16_t *)s;
> -#endif
> +			iowrite16(*(const uint16_t *)s, (void *)reg);
>  		} else {
>  			size = 1;
> -#if defined(RTE_ARCH_X86)
> -			outb_p(*s, reg);
> -#else
> -			*(volatile uint8_t *)reg = *s;
> -#endif
> +			iowrite8(*s, (void *)reg);
>  		}
>  	}
>  }
>