[PATCH] PCI: Designware: remove wrong RC memory base/limit configuration

[PATCH] PCI: Designware: remove wrong RC memory base/limit configuration

[Gabriele Paoloni]

From: gabriele paoloni <gabriele.paoloni@huawei.com>

Currently dw_pcie_setup_rc configures memory base and memory
limit in the type1 configuration header for the root complex.
In doing so it uses the cpu address (pp->mem_base) rather than
the bus address (pp->mem_bus_addr): this is wrong and it is
useless since the configuration is overwritten later on when
pci_bus_assign_resources() is called.

Therefore this patch just removes this configuration from
dw_pcie_setup_rc.

Signed-off-by: Gabriele Paoloni <gabriele.paoloni@huawei.com>
---
 drivers/pci/host/pcie-designware.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index a4cccd3..e48c2cb 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -788,12 +788,6 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
 	val |= 0x00010100;
 	dw_pcie_writel_rc(pp, val, PCI_PRIMARY_BUS);
 
-	/* setup memory base, memory limit */
-	membase = ((u32)pp->mem_base & 0xfff00000) >> 16;
-	memlimit = (pp->mem_size + (u32)pp->mem_base) & 0xfff00000;
-	val = memlimit | membase;
-	dw_pcie_writel_rc(pp, val, PCI_MEMORY_BASE);
-
 	/* setup command register */
 	dw_pcie_readl_rc(pp, PCI_COMMAND, &val);
 	val &= 0xffff0000;
-- 
1.9.1

Re: [PATCH] PCI: Designware: remove wrong RC memory base/limit configuration

[kbuild test robot]

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Hi gabriele,

[auto build test WARNING on pci/next]
[also build test WARNING on v4.6-rc3 next-20160415]
[if your patch is applied to the wrong git tree, please drop us a note to help improving the system]

url:    https://github.com/0day-ci/linux/commits/Gabriele-Paoloni/PCI-Designware-remove-wrong-RC-memory-base-limit-configuration/20160416-000746
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: x86_64-randconfig-x011-201615 (attached as .config)
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   drivers/pci/host/pcie-designware.c: In function 'dw_pcie_setup_rc':
>> drivers/pci/host/pcie-designware.c:732:6: warning: unused variable 'memlimit' [-Wunused-variable]
     u32 memlimit;
         ^
>> drivers/pci/host/pcie-designware.c:731:6: warning: unused variable 'membase' [-Wunused-variable]
     u32 membase;
         ^

vim +/memlimit +732 drivers/pci/host/pcie-designware.c

4b1ced84 Jingoo Han    2013-07-31  725  	.write = dw_pcie_wr_conf,
340cba60 Jingoo Han    2013-06-21  726  };
340cba60 Jingoo Han    2013-06-21  727  
4b1ced84 Jingoo Han    2013-07-31  728  void dw_pcie_setup_rc(struct pcie_port *pp)
340cba60 Jingoo Han    2013-06-21  729  {
340cba60 Jingoo Han    2013-06-21  730  	u32 val;
340cba60 Jingoo Han    2013-06-21 @731  	u32 membase;
340cba60 Jingoo Han    2013-06-21 @732  	u32 memlimit;
340cba60 Jingoo Han    2013-06-21  733  
66c5c34b Mohit Kumar   2014-04-14  734  	/* set the number of lanes */
f7b7868c Seungwon Jeon 2013-08-28  735  	dw_pcie_readl_rc(pp, PCIE_PORT_LINK_CONTROL, &val);

:::::: The code at line 732 was first introduced by commit
:::::: 340cba6092c2c1688629d327b74e7eb746a571a7 pci: Add PCIe driver for Samsung Exynos

:::::: TO: Jingoo Han <jg1.han@samsung.com>
:::::: CC: Arnd Bergmann <arnd@arndb.de>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

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RE: [PATCH] PCI: Designware: remove wrong RC memory base/limit configuration

[Gabriele Paoloni]

> -----Original Message-----
> From: kbuild test robot [mailto:lkp@intel.com]
> Sent: 15 April 2016 17:24
> To: Gabriele Paoloni
> Cc: kbuild-all@01.org; pratyush.anand@gmail.com; jingoohan1@gmail.com;
> Gabriele Paoloni; Linuxarm; linux-pci@vger.kernel.org; linux-
> kernel@vger.kernel.org; helgaas@kernel.org
> Subject: Re: [PATCH] PCI: Designware: remove wrong RC memory base/limit
> configuration
> 
> Hi gabriele,
> 
> [auto build test WARNING on pci/next]
> [also build test WARNING on v4.6-rc3 next-20160415]
> [if your patch is applied to the wrong git tree, please drop us a note
> to help improving the system]
> 
> url:    https://github.com/0day-ci/linux/commits/Gabriele-Paoloni/PCI-
> Designware-remove-wrong-RC-memory-base-limit-configuration/20160416-
> 000746
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git
> next
> config: x86_64-randconfig-x011-201615 (attached as .config)
> reproduce:
>         # save the attached .config to linux build tree
>         make ARCH=x86_64
> 
> All warnings (new ones prefixed by >>):
> 
>    drivers/pci/host/pcie-designware.c: In function 'dw_pcie_setup_rc':
> >> drivers/pci/host/pcie-designware.c:732:6: warning: unused variable
> 'memlimit' [-Wunused-variable]
>      u32 memlimit;
>          ^
> >> drivers/pci/host/pcie-designware.c:731:6: warning: unused variable
> 'membase' [-Wunused-variable]
>      u32 membase;
>          ^

Just sent v2 to fix this

Gab

> 
> vim +/memlimit +732 drivers/pci/host/pcie-designware.c
> 
> 4b1ced84 Jingoo Han    2013-07-31  725  	.write = dw_pcie_wr_conf,
> 340cba60 Jingoo Han    2013-06-21  726  };
> 340cba60 Jingoo Han    2013-06-21  727
> 4b1ced84 Jingoo Han    2013-07-31  728  void dw_pcie_setup_rc(struct
> pcie_port *pp)
> 340cba60 Jingoo Han    2013-06-21  729  {
> 340cba60 Jingoo Han    2013-06-21  730  	u32 val;
> 340cba60 Jingoo Han    2013-06-21 @731  	u32 membase;
> 340cba60 Jingoo Han    2013-06-21 @732  	u32 memlimit;
> 340cba60 Jingoo Han    2013-06-21  733
> 66c5c34b Mohit Kumar   2014-04-14  734  	/* set the number of lanes */
> f7b7868c Seungwon Jeon 2013-08-28  735  	dw_pcie_readl_rc(pp,
> PCIE_PORT_LINK_CONTROL, &val);
> 
> :::::: The code at line 732 was first introduced by commit
> :::::: 340cba6092c2c1688629d327b74e7eb746a571a7 pci: Add PCIe driver
> for Samsung Exynos
> 
> :::::: TO: Jingoo Han <jg1.han@samsung.com>
> :::::: CC: Arnd Bergmann <arnd@arndb.de>
> 
> ---
> 0-DAY kernel test infrastructure                Open Source Technology
> Center
> https://lists.01.org/pipermail/kbuild-all                   Intel
> Corporation