RE: [PATCH v2 3/3] edac: Supporting AST2400 and AST2600 edac driver

[Troy Lee <troy_lee@aspeedtech.com>]

Hi Joel,

Thanks for the suggestion, I'll fix the review and create an new patch against 
latest Linux branch. Those exported function will be referenced in other driver yet 
to be upstream, so should I move those exported functions out of this patch?

Thanks,
Troy Lee

> -----Original Message-----
> From: Joel Stanley <joel@jms.id.au>
> Sent: Wednesday, December 2, 2020 3:02 PM
> To: Troy Lee <troy_lee@aspeedtech.com>
> Cc: Stefan Schaeckeler <sschaeck@cisco.com>; Rob Herring
> <robh+dt@kernel.org>; Andrew Jeffery <andrew@aj.id.au>; Borislav Petkov
> <bp@alien8.de>; Mauro Carvalho Chehab <mchehab@kernel.org>; Tony Luck
> <tony.luck@intel.com>; James Morse <james.morse@arm.com>; Robert
> Richter <rrichter@marvell.com>; open list:OPEN FIRMWARE AND FLATTENED
> DEVICE TREE BINDINGS <devicetree@vger.kernel.org>; moderated
> list:ARM/ASPEED MACHINE SUPPORT <linux-arm-kernel@lists.infradead.org>;
> moderated list:ARM/ASPEED MACHINE SUPPORT
> <linux-aspeed@lists.ozlabs.org>; open list <linux-kernel@vger.kernel.org>;
> open list:EDAC-CORE <linux-edac@vger.kernel.org>; leetroy@gmail.com; Ryan
> Chen <ryan_chen@aspeedtech.com>
> Subject: Re: [PATCH v2 3/3] edac: Supporting AST2400 and AST2600 edac
> driver
> 
> On Wed, 2 Dec 2020 at 06:37, Troy Lee <troy_lee@aspeedtech.com> wrote:
> >
> > Adding AST2400 and AST2600 edac driver support.
> >
> > Signed-off-by: Troy Lee <troy_lee@aspeedtech.com>
> > ---
> > Change since v1:
> > 1. Removing SoC specific code
> > 2. Changing numerical representation of memory sizing
> > ---
> >  drivers/edac/Kconfig       |   6 +--
> >  drivers/edac/aspeed_edac.c | 103
> > +++++++++++++++++++++++++++++--------
> >  2 files changed, 85 insertions(+), 24 deletions(-)
> >
> > diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig index
> > fc30f2ef9782..8ea70746d0bf 100644
> > --- a/drivers/edac/Kconfig
> > +++ b/drivers/edac/Kconfig
> > @@ -508,10 +508,10 @@ config EDAC_QCOM
> >           health, you should probably say 'Y' here.
> >
> >  config EDAC_ASPEED
> > -       tristate "Aspeed AST 2500 SoC"
> > -       depends on MACH_ASPEED_G5
> > +       tristate "Aspeed AST BMC SoC"
> > +       depends on (MACH_ASPEED_G4 || MACH_ASPEED_G5 ||
> > + MACH_ASPEED_G6)
> 
> Change this to ARCH_ASPEED.
> 
Fixed.

> >         help
> > -         Support for error detection and correction on the Aspeed AST
> 2500 SoC.
> > +         Support for error detection and correction on the Aspeed AST
> BMC SoC.
> >
> >           First, ECC must be configured in the bootloader. Then, this
> driver
> >           will expose error counters via the EDAC kernel framework.
> > diff --git a/drivers/edac/aspeed_edac.c b/drivers/edac/aspeed_edac.c
> > index fbec28dc661d..b8c8d6a05f91 100644
> > --- a/drivers/edac/aspeed_edac.c
> > +++ b/drivers/edac/aspeed_edac.c
> > @@ -14,12 +14,11 @@
> >  #include <linux/regmap.h>
> >  #include "edac_module.h"
> >
> > -
> 
> These whitespace cleanups are ok, but can probably go in a different patch so
> they aren't mixed up with the functional changes.
> 
Okay, that make sense.

> >  #define DRV_NAME "aspeed-edac"
> >
> > -
> >  #define ASPEED_MCR_PROT        0x00 /* protection key register */
> >  #define ASPEED_MCR_CONF        0x04 /* configuration register */
> > +#define ASPEED_MCR_REQ         0x08 /* Graphics Memory Protection
> register */
> >  #define ASPEED_MCR_INTR_CTRL   0x50 /* interrupt control/status
> register */
> >  #define ASPEED_MCR_ADDR_UNREC  0x58 /* address of first
> un-recoverable error */
> >  #define ASPEED_MCR_ADDR_REC    0x5c /* address of last recoverable
> error */
> > @@ -29,15 +28,17 @@
> >  #define ASPEED_MCR_PROT_PASSWD             0xfc600309
> >  #define ASPEED_MCR_CONF_DRAM_TYPE               BIT(4)
> >  #define ASPEED_MCR_CONF_ECC                     BIT(7)
> > +#define ASPEED_MCR_CONF_DRAM_CTRL_TYPE
> > +(BIT(28)|BIT(29)|BIT(30)|BIT(31))
> 
> We can use GENMASK here:
> 
>  GENMASK(31, 28)
> 
> >  #define ASPEED_MCR_INTR_CTRL_CLEAR             BIT(31)
> >  #define ASPEED_MCR_INTR_CTRL_CNT_REC   GENMASK(23, 16)
> >  #define ASPEED_MCR_INTR_CTRL_CNT_UNREC GENMASK(15, 12)
> #define
> > ASPEED_MCR_INTR_CTRL_ENABLE  (BIT(0) | BIT(1))
> >
> > +#define ASPEED_MCR_CONF_DRAM_CTRL_TYPE_AST2500  0x01 #define
> > +ASPEED_MCR_CONF_DRAM_CTRL_TYPE_AST2600  0x03
> >
> >  static struct regmap *aspeed_regmap;
> >
> > -
> >  static int regmap_reg_write(void *context, unsigned int reg, unsigned
> > int val)  {
> >         void __iomem *regs = (void __iomem *)context; @@ -53,7 +54,6
> > @@ static int regmap_reg_write(void *context, unsigned int reg, unsigned
> int val)
> >         return 0;
> >  }
> >
> > -
> >  static int regmap_reg_read(void *context, unsigned int reg, unsigned
> > int *val)  {
> >         void __iomem *regs = (void __iomem *)context; @@ -63,6 +63,79
> > @@ static int regmap_reg_read(void *context, unsigned int reg, unsigned int
> *val)
> >         return 0;
> >  }
> >
> > +extern void aspeed_sdmc_disable_mem_protection(u8 req) {
> > +       u32 req_val = 0;
> > +
> > +       regmap_read(aspeed_regmap, ASPEED_MCR_REQ, &req_val);
> > +
> > +       req_val &= ~BIT(req);
> > +
> > +       regmap_write(aspeed_regmap, ASPEED_MCR_REQ, req_val);
> 
> This is open coding regmap_update_bits:
> 
>   regmap_update_bits(aspeed_regmap, ASPEED_MCR_REQ, BIT(req),
> BIT(req));
> 
> > +}
> > +EXPORT_SYMBOL(aspeed_sdmc_disable_mem_protection);
> 
> I don't think any of these functions need to be exported. The same comment
> applies to the functions below this one; you can make them all static and drop
> the extern and the EXPORT_SYMBOL.
> 
> > +
> > +static const u32 ast2400_dram_table[] = {
> > +       64 << 20,
> > +       128 << 20,
> > +       256 << 20,
> > +       512 << 20,
> > +};
> > +
> > +static const u32 ast2500_dram_table[] = {
> > +       128 << 20,
> > +       256 << 20,
> > +       512 << 20,
> > +       1024 << 20,
> > +};
> > +
> > +static const u32 ast2600_dram_table[] = {
> > +       256 << 20,
> > +       512 << 20,
> > +       1024 << 20,
> > +       2048 << 20,
> > +};
> > +
> > +extern u32 aspeed_get_dram_size(void) {
> > +       u32 reg04;
> > +       u32 size;
> > +       u8 type;
> > +
> > +       regmap_read(aspeed_regmap, ASPEED_MCR_CONF, &reg04);
> > +
> > +       type = (reg04 & ASPEED_MCR_CONF_DRAM_CTRL_TYPE) >> 28;
> > +
> > +       if (type == ASPEED_MCR_CONF_DRAM_CTRL_TYPE_AST2600)
> > +               size = ast2600_dram_table[reg04 & 0x3];
> > +       else if (type == ASPEED_MCR_CONF_DRAM_CTRL_TYPE_AST2500)
> > +               size = ast2500_dram_table[reg04 & 0x3];
> > +       else
> > +               size = ast2400_dram_table[reg04 & 0x3];
> > +
> > +       return size;
> > +}
> > +EXPORT_SYMBOL(aspeed_get_dram_size);
> > +
> > +static const u32 aspeed_vga_table[] = {
> > +       8 << 20,
> > +       16 << 20,
> > +       32 << 20,
> > +       64 << 20,
> > +};
> > +
> > +extern u32 aspeed_get_vga_size(void)
> > +{
> > +       u32 reg04;
> > +       u32 size;
> > +
> > +       regmap_read(aspeed_regmap, ASPEED_MCR_CONF, &reg04);
> > +
> > +       size = aspeed_vga_table[((reg04 & 0xC) >> 2)];
> > +       return size;
> 
> If you do this:
> 
>  return aspeed_vga_table[((reg04 & 0xC) >> 2)]
> 
> You can drop 'size'.
> 
> > +}
> > +EXPORT_SYMBOL(aspeed_get_vga_size);
> > +
> >  static bool regmap_is_volatile(struct device *dev, unsigned int reg)
> > {
> >         switch (reg) {
> > @@ -227,7 +300,6 @@ static int config_irq(void *ctx, struct platform_device
> *pdev)
> >         return 0;
> >  }
> >
> > -
> >  static int init_csrows(struct mem_ctl_info *mci)  {
> >         struct csrow_info *csrow = mci->csrows[0]; @@ -239,7 +311,7
> @@
> > static int init_csrows(struct mem_ctl_info *mci)
> >         int rc;
> >
> >         /* retrieve info about physical memory from device tree */
> > -       np = of_find_node_by_path("/memory");
> > +       np = of_find_node_by_name(NULL, "memory");
> >         if (!np) {
> >                 dev_err(mci->pdev, "dt: missing /memory node\n");
> >                 return -ENODEV;
> > @@ -275,14 +347,12 @@ static int init_csrows(struct mem_ctl_info *mci)
> >         return 0;
> >  }
> >
> > -
> >  static int aspeed_probe(struct platform_device *pdev)  {
> >         struct device *dev = &pdev->dev;
> >         struct edac_mc_layer layers[2];
> >         struct mem_ctl_info *mci;
> >         void __iomem *regs;
> > -       u32 reg04;
> >         int rc;
> >
> >         regs = devm_platform_ioremap_resource(pdev, 0); @@ -294,13
> > +364,6 @@ static int aspeed_probe(struct platform_device *pdev)
> >         if (IS_ERR(aspeed_regmap))
> >                 return PTR_ERR(aspeed_regmap);
> >
> > -       /* bail out if ECC mode is not configured */
> > -       regmap_read(aspeed_regmap, ASPEED_MCR_CONF, &reg04);
> > -       if (!(reg04 & ASPEED_MCR_CONF_ECC)) {
> > -               dev_err(&pdev->dev, "ECC mode is not configured in
> u-boot\n");
> > -               return -EPERM;
> > -       }
> > -
> >         edac_op_state = EDAC_OPSTATE_INT;
> >
> >         /* allocate & init EDAC MC data structure */ @@ -373,12
> > +436,13 @@ static int aspeed_remove(struct platform_device *pdev)
> >         return 0;
> >  }
> >
> > -
> >  static const struct of_device_id aspeed_of_match[] = {
> > +       { .compatible = "aspeed,ast2400-sdram-edac" },
> >         { .compatible = "aspeed,ast2500-sdram-edac" },
> > +       { .compatible = "aspeed,ast2600-sdram-edac" },
> >         {},
> >  };
> > -
> > +MODULE_DEVICE_TABLE(of, aspeed_of_match);
> >
> >  static struct platform_driver aspeed_driver = {
> >         .driver         = {
> > @@ -395,18 +459,15 @@ static int __init aspeed_init(void)
> >         return platform_driver_register(&aspeed_driver);
> >  }
> >
> > -
> >  static void __exit aspeed_exit(void)
> >  {
> >         platform_driver_unregister(&aspeed_driver);
> >  }
> >
> > -
> >  module_init(aspeed_init);
> >  module_exit(aspeed_exit);
> 
> Unrelated, you can clean up the above 6 lines with module_platform_driver().
> 
> Actually, looking at the kernel tree this was already done in v5.9.
> Please send your next version based on the latest kernel, eg v5.10-rc1.
> 
> Cheers,
> 
> Joel
> 
Good suggestion.

> >
> > -
> >  MODULE_LICENSE("GPL");
> >  MODULE_AUTHOR("Stefan Schaeckeler <sschaeck@cisco.com>");
> > -MODULE_DESCRIPTION("Aspeed AST2500 EDAC driver");
> > +MODULE_DESCRIPTION("Aspeed EDAC driver");
> >  MODULE_VERSION("1.0");
> > --
> > 2.17.1
> >