Re: [PATCH 3/3] edac: Supporting AST2400 and AST2600 edac driver
From: Andrew Jeffery
Date: Mon Nov 30 2020 - 20:13:29 EST
Hi Troy,
I like the idea of expanding the driver's support to cover the other SoC
generations, but not at the cost of making the build of the driver
SoC-specific. I've made some comments below in this regard.
On Mon, 30 Nov 2020, at 19:03, Troy Lee wrote:
> Adding AST2400 and AST2600 edac driver support.
>
> Signed-off-by: Troy Lee <troy_lee@xxxxxxxxxxxxxx>
> ---
> drivers/edac/Kconfig | 6 +-
> drivers/edac/aspeed_edac.c | 114 +++++++++++++++++++++++++++++--------
> 2 files changed, 94 insertions(+), 26 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)
> 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..03a3c12f6bf6 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"
>
> -
> #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 */
> @@ -34,10 +33,8 @@
> #define ASPEED_MCR_INTR_CTRL_CNT_UNREC GENMASK(15, 12)
> #define ASPEED_MCR_INTR_CTRL_ENABLE (BIT(0) | BIT(1))
>
> -
> 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 +50,6 @@ 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 +59,76 @@ 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);
> +}
> +EXPORT_SYMBOL(aspeed_sdmc_disable_mem_protection);
> +
> +static const u32 ast2400_dram_table[] = {
> + 0x04000000, //64MB
> + 0x08000000, //128MB
> + 0x10000000, //256MB
> + 0x20000000, //512MB
> +};
You could perhaps save us from the size comments here by using e.g.
static const u32 ast2400_dram_table[] = {
64 << 20,
128 << 20,
256 << 20,
512 << 20,
};
> +
> +static const u32 ast2500_dram_table[] = {
> + 0x08000000, //128MB
> + 0x10000000, //256MB
> + 0x20000000, //512MB
> + 0x40000000, //1024MB
> +};
> +
> +static const u32 ast2600_dram_table[] = {
> + 0x10000000, //256MB
> + 0x20000000, //512MB
> + 0x40000000, //1024MB
> + 0x80000000, //2048MB
> +};
> +
> +extern u32 aspeed_get_dram_size(void)
> +{
> + u32 reg04;
> + u32 size;
> +
> + regmap_read(aspeed_regmap, ASPEED_MCR_CONF, ®04);
> +
> +#if defined(CONFIG_MACH_ASPEED_G6)
> + size = ast2600_dram_table[reg04 & 0x3];
> +#elif defined(CONFIG_MACH_ASPEED_G5)
> + size = ast2500_dram_table[reg04 & 0x3];
> +#else
> + size = ast2400_dram_table[reg04 & 0x3];
> +#endif
> + return size;
> +}
> +EXPORT_SYMBOL(aspeed_get_dram_size);
The driver must support running on any of the SoC generations without being
recompiled. This requires the driver be compiled for a specific SoC generation.
The right way to do this is to use the OF match table data. Please fix it.
> +
> +static const u32 aspeed_vga_table[] = {
> + 0x800000, //8MB
> + 0x1000000, //16MB
> + 0x2000000, //32MB
> + 0x4000000, //64MB
> +};
> +
> +extern u32 aspeed_get_vga_size(void)
> +{
> + u32 reg04;
> + u32 size;
> +
> + regmap_read(aspeed_regmap, ASPEED_MCR_CONF, ®04);
> +
> + size = aspeed_vga_table[((reg04 & 0xC) >> 2)];
> + return size;
> +}
> +EXPORT_SYMBOL(aspeed_get_vga_size);
> +
> static bool regmap_is_volatile(struct device *dev, unsigned int reg)
> {
> switch (reg) {
> @@ -209,8 +275,8 @@ static int config_irq(void *ctx, struct
> platform_device *pdev)
> /* register interrupt handler */
> irq = platform_get_irq(pdev, 0);
> dev_dbg(&pdev->dev, "got irq %d\n", irq);
> - if (irq < 0)
> - return irq;
> + if (!irq)
> + return -ENODEV;
The documentation for platform_get_irq() says "Return: IRQ number on success, negative error number on failure."
So this change doesn't look right.
>
> rc = devm_request_irq(&pdev->dev, irq, mcr_isr, IRQF_TRIGGER_HIGH,
> DRV_NAME, ctx);
> @@ -239,7 +305,11 @@ 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");
> +#ifdef CONFIG_MACH_ASPEED_G4
> + np = of_find_node_by_path("/memory@40000000");
> +#else
> + np = of_find_node_by_path("/memory@80000000");
> +#endif
Again, this makes the driver SoC-specific at compile time, and that's not going
to fly. If we need it, this should be solved with a phandle to the appropriate
memory node.
> if (!np) {
> dev_err(mci->pdev, "dt: missing /memory node\n");
> return -ENODEV;
> @@ -281,11 +351,19 @@ static int aspeed_probe(struct platform_device *pdev)
> struct device *dev = &pdev->dev;
> struct edac_mc_layer layers[2];
> struct mem_ctl_info *mci;
> + struct device_node *np;
> + struct resource *res;
> void __iomem *regs;
> - u32 reg04;
> int rc;
>
> - regs = devm_platform_ioremap_resource(pdev, 0);
> + /* setup regmap */
> + np = dev->of_node;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!res)
> + return -ENOENT;
> +
> + regs = devm_ioremap_resource(dev, res);
> if (IS_ERR(regs))
> return PTR_ERR(regs);
Why is this change necessary?
>
> @@ -294,13 +372,6 @@ 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, ®04);
> - if (!(reg04 & ASPEED_MCR_CONF_ECC)) {
> - dev_err(&pdev->dev, "ECC mode is not configured in u-boot\n");
> - return -EPERM;
> - }
> -
Why shouldn't we do this check?
> edac_op_state = EDAC_OPSTATE_INT;
>
> /* allocate & init EDAC MC data structure */
> @@ -373,13 +444,13 @@ 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" },
The .data member of struct of_device_id is where you need to attach your
SoC-generation-specific data.
Cheers,
Andrew
> {},
> };
>
> -
> static struct platform_driver aspeed_driver = {
> .driver = {
> .name = DRV_NAME,
> @@ -395,18 +466,15 @@ 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);
>
> -
> MODULE_LICENSE("GPL");
> MODULE_AUTHOR("Stefan Schaeckeler <sschaeck@xxxxxxxxx>");
> -MODULE_DESCRIPTION("Aspeed AST2500 EDAC driver");
> +MODULE_DESCRIPTION("Aspeed EDAC driver");
> MODULE_VERSION("1.0");
> --
> 2.17.1
>
>