From 2f26e6189d3bdfcbf2b3bd0d6ff88eb8e7022246 Mon Sep 17 00:00:00 2001 From: Ludovic Desroches Date: Fri, 18 Mar 2016 08:21:19 +0100 Subject: [PATCH] ARM: at91: use chipid device for soc detection So far, the CIDR and EXID registers were in the DBGU interface. This device has disappeared with the SAMA5D2 family. These registers are exposed through a new device called chipid. Signed-off-by: Ludovic Desroches [nicolas.ferre@atmel.com: remove useless warnings] Acked-by: Alexandre Belloni Acked-by: Rob Herring [arnd@arndb.de: suggest to use static functions to reduce scope] Acked-by: Arnd Bergmann Signed-off-by: Nicolas Ferre --- .../devicetree/bindings/arm/atmel-at91.txt | 4 + arch/arm/mach-at91/soc.c | 85 ++++++++++++++----- 2 files changed, 69 insertions(+), 20 deletions(-) diff --git a/Documentation/devicetree/bindings/arm/atmel-at91.txt b/Documentation/devicetree/bindings/arm/atmel-at91.txt index 7fd64ec9ee1d..0b1fcbfe2299 100644 --- a/Documentation/devicetree/bindings/arm/atmel-at91.txt +++ b/Documentation/devicetree/bindings/arm/atmel-at91.txt @@ -41,6 +41,10 @@ compatible: must be one of: - "atmel,sama5d43" - "atmel,sama5d44" +Chipid required properties: +- compatible: Should be "atmel,sama5d2-chipid" +- reg : Should contain registers location and length + PIT Timer required properties: - compatible: Should be "atmel,at91sam9260-pit" - reg: Should contain registers location and length diff --git a/arch/arm/mach-at91/soc.c b/arch/arm/mach-at91/soc.c index 54343ffa3e53..c6fda75ddb89 100644 --- a/arch/arm/mach-at91/soc.c +++ b/arch/arm/mach-at91/soc.c @@ -22,48 +22,93 @@ #include "soc.h" #define AT91_DBGU_CIDR 0x40 -#define AT91_DBGU_CIDR_VERSION(x) ((x) & 0x1f) -#define AT91_DBGU_CIDR_EXT BIT(31) -#define AT91_DBGU_CIDR_MATCH_MASK 0x7fffffe0 #define AT91_DBGU_EXID 0x44 +#define AT91_CHIPID_CIDR 0x00 +#define AT91_CHIPID_EXID 0x04 +#define AT91_CIDR_VERSION(x) ((x) & 0x1f) +#define AT91_CIDR_EXT BIT(31) +#define AT91_CIDR_MATCH_MASK 0x7fffffe0 -struct soc_device * __init at91_soc_init(const struct at91_soc *socs) +static int __init at91_get_cidr_exid_from_dbgu(u32 *cidr, u32 *exid) { - struct soc_device_attribute *soc_dev_attr; - const struct at91_soc *soc; - struct soc_device *soc_dev; struct device_node *np; void __iomem *regs; - u32 cidr, exid; np = of_find_compatible_node(NULL, NULL, "atmel,at91rm9200-dbgu"); if (!np) np = of_find_compatible_node(NULL, NULL, "atmel,at91sam9260-dbgu"); - - if (!np) { - pr_warn("Could not find DBGU node"); - return NULL; - } + if (!np) + return -ENODEV; regs = of_iomap(np, 0); of_node_put(np); if (!regs) { pr_warn("Could not map DBGU iomem range"); - return NULL; + return -ENXIO; } - cidr = readl(regs + AT91_DBGU_CIDR); - exid = readl(regs + AT91_DBGU_EXID); + *cidr = readl(regs + AT91_DBGU_CIDR); + *exid = readl(regs + AT91_DBGU_EXID); iounmap(regs); + return 0; +} + +static int __init at91_get_cidr_exid_from_chipid(u32 *cidr, u32 *exid) +{ + struct device_node *np; + void __iomem *regs; + + np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-chipid"); + if (!np) + return -ENODEV; + + regs = of_iomap(np, 0); + of_node_put(np); + + if (!regs) { + pr_warn("Could not map DBGU iomem range"); + return -ENXIO; + } + + *cidr = readl(regs + AT91_CHIPID_CIDR); + *exid = readl(regs + AT91_CHIPID_EXID); + + iounmap(regs); + + return 0; +} + +struct soc_device * __init at91_soc_init(const struct at91_soc *socs) +{ + struct soc_device_attribute *soc_dev_attr; + const struct at91_soc *soc; + struct soc_device *soc_dev; + u32 cidr, exid; + int ret; + + /* + * With SAMA5D2 and later SoCs, CIDR and EXID registers are no more + * in the dbgu device but in the chipid device whose purpose is only + * to expose these two registers. + */ + ret = at91_get_cidr_exid_from_dbgu(&cidr, &exid); + if (ret) + ret = at91_get_cidr_exid_from_chipid(&cidr, &exid); + if (ret) { + if (ret == -ENODEV) + pr_warn("Could not find identification node"); + return NULL; + } + for (soc = socs; soc->name; soc++) { - if (soc->cidr_match != (cidr & AT91_DBGU_CIDR_MATCH_MASK)) + if (soc->cidr_match != (cidr & AT91_CIDR_MATCH_MASK)) continue; - if (!(cidr & AT91_DBGU_CIDR_EXT) || soc->exid_match == exid) + if (!(cidr & AT91_CIDR_EXT) || soc->exid_match == exid) break; } @@ -79,7 +124,7 @@ struct soc_device * __init at91_soc_init(const struct at91_soc *socs) soc_dev_attr->family = soc->family; soc_dev_attr->soc_id = soc->name; soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%X", - AT91_DBGU_CIDR_VERSION(cidr)); + AT91_CIDR_VERSION(cidr)); soc_dev = soc_device_register(soc_dev_attr); if (IS_ERR(soc_dev)) { kfree(soc_dev_attr->revision); @@ -91,7 +136,7 @@ struct soc_device * __init at91_soc_init(const struct at91_soc *socs) if (soc->family) pr_info("Detected SoC family: %s\n", soc->family); pr_info("Detected SoC: %s, revision %X\n", soc->name, - AT91_DBGU_CIDR_VERSION(cidr)); + AT91_CIDR_VERSION(cidr)); return soc_dev; }