Message-ID: <1461763453.20711.7.camel@redhat.com>
Subject: Re: [PATCH] IPMI: reserve memio regions separately
From: Mark Salter <msalter@redhat.com>
To: minyard@acm.org
Cc: openipmi-developer@lists.sourceforge.net, linux-kernel@vger.kernel.org,
        Corey Minyard <cminyard@mvista.com>
Date: Wed, 27 Apr 2016 09:24:13 -0400
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References: <1461600515-26617-1-git-send-email-msalter@redhat.com>
	 <1461731468-10585-1-git-send-email-minyard@acm.org>
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On Tue, 2016-04-26 at 23:31 -0500, minyard@acm.org wrote:
> From: Corey Minyard <cminyard@mvista.com>
> 
> Commit d61a3ead2680 ("[PATCH] IPMI: reserve I/O ports separately")
> changed the way I/O ports were reserved and includes this comment in
> log:
> 
>  Some BIOSes reserve disjoint I/O regions in their ACPI tables for the IPMI
>  controller.  This causes problems when trying to register the entire I/O
>  region.  Therefore we must register each I/O port separately.
> 
> There is a similar problem with memio regions on an arm64 platform
> (AMD Seattle). Where I see:
> 
>  ipmi message handler version 39.2
>  ipmi_si AMDI0300:00: probing via device tree
>  ipmi_si AMDI0300:00: ipmi_si: probing via ACPI
>  ipmi_si AMDI0300:00: [mem 0xe0010000] regsize 1 spacing 4 irq 23
>  ipmi_si: Adding ACPI-specified kcs state machine
>  IPMI System Interface driver.
>  ipmi_si: Trying ACPI-specified kcs state machine at mem \
>           address 0xe0010000, slave address 0x0, irq 23
>  ipmi_si: Could not set up I/O space
> 
> The problem is that the ACPI core registers disjoint regions for the
> platform device:
> 
> e0010000-e0010000 : AMDI0300:00
> e0010004-e0010004 : AMDI0300:00
> 
> and the ipmi_si driver tries to register one region e0010000-e0010004.
> 
> Based on a patch from Mark Salter <msalter@redhat.com>
> 
> Signed-off-by: Corey Minyard <cminyard@mvista.com>
> ---

This works for me as well.

Tested-by: Mark Salter <msalter@redhat.com>

>  drivers/char/ipmi/ipmi_si_intf.c | 40 +++++++++++++++++++++++++++-------------
>  1 file changed, 27 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
> index 6ecf9af..a815044 100644
> --- a/drivers/char/ipmi/ipmi_si_intf.c
> +++ b/drivers/char/ipmi/ipmi_si_intf.c
> @@ -1637,25 +1637,28 @@ static void mem_outq(const struct si_sm_io *io, unsigned int offset,
>  }
>  #endif
>  
> -static void mem_cleanup(struct smi_info *info)
> +static void mem_region_cleanup(struct smi_info *info, int num)
>  {
>  	unsigned long addr = info->io.addr_data;
> -	int           mapsize;
> +	int idx;
> +
> +	for (idx = 0; idx < num; idx++)
> +		release_mem_region(addr + idx * info->io.regspacing,
> +				   info->io.regsize);
> +}
>  
> +static void mem_cleanup(struct smi_info *info)
> +{
>  	if (info->io.addr) {
>  		iounmap(info->io.addr);
> -
> -		mapsize = ((info->io_size * info->io.regspacing)
> -			   - (info->io.regspacing - info->io.regsize));
> -
> -		release_mem_region(addr, mapsize);
> +		mem_region_cleanup(info, info->io_size);
>  	}
>  }
>  
>  static int mem_setup(struct smi_info *info)
>  {
>  	unsigned long addr = info->io.addr_data;
> -	int           mapsize;
> +	int           mapsize, idx;
>  
>  	if (!addr)
>  		return -ENODEV;
> @@ -1692,6 +1695,21 @@ static int mem_setup(struct smi_info *info)
>  	}
>  
>  	/*
> +	 * Some BIOSes reserve disjoint memory regions in their ACPI
> +	 * tables.  This causes problems when trying to request the
> +	 * entire region.  Therefore we must request each register
> +	 * separately.
> +	 */
> +	for (idx = 0; idx < info->io_size; idx++) {
> +		if (request_mem_region(addr + idx * info->io.regspacing,
> +				       info->io.regsize, DEVICE_NAME) == NULL) {
> +			/* Undo allocations */
> +			mem_region_cleanup(info, idx);
> +			return -EIO;
> +		}
> +	}
> +
> +	/*
>  	 * Calculate the total amount of memory to claim.  This is an
>  	 * unusual looking calculation, but it avoids claiming any
>  	 * more memory than it has to.  It will claim everything
> @@ -1700,13 +1718,9 @@ static int mem_setup(struct smi_info *info)
>  	 */
>  	mapsize = ((info->io_size * info->io.regspacing)
>  		   - (info->io.regspacing - info->io.regsize));
> -
> -	if (request_mem_region(addr, mapsize, DEVICE_NAME) == NULL)
> -		return -EIO;
> -
>  	info->io.addr = ioremap(addr, mapsize);
>  	if (info->io.addr == NULL) {
> -		release_mem_region(addr, mapsize);
> +		mem_region_cleanup(info, info->io_size);
>  		return -EIO;
>  	}
>  	return 0;