EDAC, altera: Add Arria10 ECC memory init functions

In preparation for additional memory module ECCs, add the memory
initialization functions and helpers.

Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1466603939-7526-7-git-send-email-tthayer@opensource.altera.com
Signed-off-by: Borislav Petkov <bp@suse.de>

2 files changed, 200 insertions, 0 deletions

diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
index 2e5940e5801e..6091b76646c4 100644
--- a/drivers/edac/altera_edac.c
+++ b/drivers/edac/altera_edac.c
@@ -19,6 +19,7 @@
 
 #include <asm/cacheflush.h>
 #include <linux/ctype.h>
+#include <linux/delay.h>
 #include <linux/edac.h>
 #include <linux/genalloc.h>
 #include <linux/interrupt.h>
@@ -874,6 +875,197 @@ static irqreturn_t __maybe_unused altr_edac_a10_ecc_irq(int irq, void *dev_id)
         return IRQ_NONE;
 }
 
+/******************* Arria10 Memory Buffer Functions *********************/
+
+static inline int a10_get_irq_mask(struct device_node *np)
+{
+        int irq;
+        const u32 *handle = of_get_property(np, "interrupts", NULL);
+
+        if (!handle)
+                return -ENODEV;
+        irq = be32_to_cpup(handle);
+        return irq;
+}
+
+static inline void ecc_set_bits(u32 bit_mask, void __iomem *ioaddr)
+{
+        u32 value = readl(ioaddr);
+
+        value |= bit_mask;
+        writel(value, ioaddr);
+}
+
+static inline void ecc_clear_bits(u32 bit_mask, void __iomem *ioaddr)
+{
+        u32 value = readl(ioaddr);
+
+        value &= ~bit_mask;
+        writel(value, ioaddr);
+}
+
+static inline int ecc_test_bits(u32 bit_mask, void __iomem *ioaddr)
+{
+        u32 value = readl(ioaddr);
+
+        return (value & bit_mask) ? 1 : 0;
+}
+
+/*
+ * This function uses the memory initialization block in the Arria10 ECC
+ * controller to initialize/clear the entire memory data and ECC data.
+ */
+static int __maybe_unused altr_init_memory_port(void __iomem *ioaddr, int port)
+{
+        int limit = ALTR_A10_ECC_INIT_WATCHDOG_10US;
+        u32 init_mask, stat_mask, clear_mask;
+        int ret = 0;
+
+        if (port) {
+                init_mask = ALTR_A10_ECC_INITB;
+                stat_mask = ALTR_A10_ECC_INITCOMPLETEB;
+                clear_mask = ALTR_A10_ECC_ERRPENB_MASK;
+        } else {
+                init_mask = ALTR_A10_ECC_INITA;
+                stat_mask = ALTR_A10_ECC_INITCOMPLETEA;
+                clear_mask = ALTR_A10_ECC_ERRPENA_MASK;
+        }
+
+        ecc_set_bits(init_mask, (ioaddr + ALTR_A10_ECC_CTRL_OFST));
+        while (limit--) {
+                if (ecc_test_bits(stat_mask,
+                                  (ioaddr + ALTR_A10_ECC_INITSTAT_OFST)))
+                        break;
+                udelay(1);
+        }
+        if (limit < 0)
+                ret = -EBUSY;
+
+        /* Clear any pending ECC interrupts */
+        writel(clear_mask, (ioaddr + ALTR_A10_ECC_INTSTAT_OFST));
+
+        return ret;
+}
+
+static __init int __maybe_unused
+altr_init_a10_ecc_block(struct device_node *np, u32 irq_mask,
+                        u32 ecc_ctrl_en_mask, bool dual_port)
+{
+        int ret = 0;
+        void __iomem *ecc_block_base;
+        struct regmap *ecc_mgr_map;
+        char *ecc_name;
+        struct device_node *np_eccmgr;
+
+        ecc_name = (char *)np->name;
+
+        /* Get the ECC Manager - parent of the device EDACs */
+        np_eccmgr = of_get_parent(np);
+        ecc_mgr_map = syscon_regmap_lookup_by_phandle(np_eccmgr,
+                                                      "altr,sysmgr-syscon");
+        of_node_put(np_eccmgr);
+        if (IS_ERR(ecc_mgr_map)) {
+                edac_printk(KERN_ERR, EDAC_DEVICE,
+                            "Unable to get syscon altr,sysmgr-syscon\n");
+                return -ENODEV;
+        }
+
+        /* Map the ECC Block */
+        ecc_block_base = of_iomap(np, 0);
+        if (!ecc_block_base) {
+                edac_printk(KERN_ERR, EDAC_DEVICE,
+                            "Unable to map %s ECC block\n", ecc_name);
+                return -ENODEV;
+        }
+
+        /* Disable ECC */
+        regmap_write(ecc_mgr_map, A10_SYSMGR_ECC_INTMASK_SET_OFST, irq_mask);
+        writel(ALTR_A10_ECC_SERRINTEN,
+               (ecc_block_base + ALTR_A10_ECC_ERRINTENR_OFST));
+        ecc_clear_bits(ecc_ctrl_en_mask,
+                       (ecc_block_base + ALTR_A10_ECC_CTRL_OFST));
+        /* Ensure all writes complete */
+        wmb();
+        /* Use HW initialization block to initialize memory for ECC */
+        ret = altr_init_memory_port(ecc_block_base, 0);
+        if (ret) {
+                edac_printk(KERN_ERR, EDAC_DEVICE,
+                            "ECC: cannot init %s PORTA memory\n", ecc_name);
+                goto out;
+        }
+
+        if (dual_port) {
+                ret = altr_init_memory_port(ecc_block_base, 1);
+                if (ret) {
+                        edac_printk(KERN_ERR, EDAC_DEVICE,
+                                    "ECC: cannot init %s PORTB memory\n",
+                                    ecc_name);
+                        goto out;
+                }
+        }
+
+        /* Interrupt mode set to every SBERR */
+        regmap_write(ecc_mgr_map, ALTR_A10_ECC_INTMODE_OFST,
+                     ALTR_A10_ECC_INTMODE);
+        /* Enable ECC */
+        ecc_set_bits(ecc_ctrl_en_mask, (ecc_block_base +
+                                        ALTR_A10_ECC_CTRL_OFST));
+        writel(ALTR_A10_ECC_SERRINTEN,
+               (ecc_block_base + ALTR_A10_ECC_ERRINTENS_OFST));
+        regmap_write(ecc_mgr_map, A10_SYSMGR_ECC_INTMASK_CLR_OFST, irq_mask);
+        /* Ensure all writes complete */
+        wmb();
+out:
+        iounmap(ecc_block_base);
+        return ret;
+}
+
+static int validate_parent_available(struct device_node *np);
+static const struct of_device_id altr_edac_a10_device_of_match[];
+static int __init __maybe_unused altr_init_a10_ecc_device_type(char *compat)
+{
+        int irq;
+        struct device_node *child, *np = of_find_compatible_node(NULL, NULL,
+                                        "altr,socfpga-a10-ecc-manager");
+        if (!np) {
+                edac_printk(KERN_ERR, EDAC_DEVICE, "ECC Manager not found\n");
+                return -ENODEV;
+        }
+
+        for_each_child_of_node(np, child) {
+                const struct of_device_id *pdev_id;
+                const struct edac_device_prv_data *prv;
+
+                if (!of_device_is_available(child))
+                        continue;
+                if (!of_device_is_compatible(child, compat))
+                        continue;
+
+                if (validate_parent_available(child))
+                        continue;
+
+                irq = a10_get_irq_mask(child);
+                if (irq < 0)
+                        continue;
+
+                /* Get matching node and check for valid result */
+                pdev_id = of_match_node(altr_edac_a10_device_of_match, child);
+                if (IS_ERR_OR_NULL(pdev_id))
+                        continue;
+
+                /* Validate private data pointer before dereferencing */
+                prv = pdev_id->data;
+                if (!prv)
+                        continue;
+
+                altr_init_a10_ecc_block(child, BIT(irq),
+                                        prv->ecc_enable_mask, 0);
+        }
+
+        of_node_put(np);
+        return 0;
+}
+
 /*********************** OCRAM EDAC Device Functions *********************/
 
 #ifdef CONFIG_EDAC_ALTERA_OCRAM
diff --git a/drivers/edac/altera_edac.h b/drivers/edac/altera_edac.h
index cf4e8cb1d120..aa7c6906d0d5 100644
--- a/drivers/edac/altera_edac.h
+++ b/drivers/edac/altera_edac.h
@@ -230,8 +230,13 @@ struct altr_sdram_mc_data {
 #define ALTR_A10_ECC_INITCOMPLETEB      BIT(8)
 
 #define ALTR_A10_ECC_ERRINTEN_OFST      0x10
+#define ALTR_A10_ECC_ERRINTENS_OFST     0x14
+#define ALTR_A10_ECC_ERRINTENR_OFST     0x18
 #define ALTR_A10_ECC_SERRINTEN          BIT(0)
 
+#define ALTR_A10_ECC_INTMODE_OFST       0x1C
+#define ALTR_A10_ECC_INTMODE            BIT(0)
+
 #define ALTR_A10_ECC_INTSTAT_OFST       0x20
 #define ALTR_A10_ECC_SERRPENA           BIT(0)
 #define ALTR_A10_ECC_DERRPENA           BIT(8)
@@ -280,6 +285,9 @@ struct altr_sdram_mc_data {
 /* Arria 10 OCRAM ECC Management Group Defines */
 #define ALTR_A10_OCRAM_ECC_EN_CTL       (BIT(1) | BIT(0))
 
+/* A10 ECC Controller memory initialization timeout */
+#define ALTR_A10_ECC_INIT_WATCHDOG_10US      10000
+
 struct altr_edac_device_dev;
 
 struct edac_device_prv_data {