[src/trunk]: src/sys/dev Handle reading of 4kbit EEPROMs in SPD devices. This...

[mlelstv <mlelstv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/8d380dabc57b
branches:  trunk
changeset: 342119:8d380dabc57b
user:      mlelstv <mlelstv%NetBSD.org@localhost>
date:      Mon Dec 07 09:41:37 2015 +0000

description:
Handle reading of 4kbit EEPROMs in SPD devices. This is needed for DDR4 DIMMs.

diffstat:

 sys/dev/i2c/spdmem_i2c.c |  66 +++++++++++++++++++++++++++++++++++++++++------
 sys/dev/ic/spdmemvar.h   |   4 +-
 2 files changed, 59 insertions(+), 11 deletions(-)

diffs (150 lines):

diff -r 191e785e47c5 -r 8d380dabc57b sys/dev/i2c/spdmem_i2c.c
--- a/sys/dev/i2c/spdmem_i2c.c  Mon Dec 07 06:28:22 2015 +0000
+++ b/sys/dev/i2c/spdmem_i2c.c  Mon Dec 07 09:41:37 2015 +0000
@@ -1,9 +1,10 @@
-/* $NetBSD: spdmem_i2c.c,v 1.10 2015/03/07 14:16:51 jmcneill Exp $ */
+/* $NetBSD: spdmem_i2c.c,v 1.11 2015/12/07 09:41:37 mlelstv Exp $ */
 
 /*
  * Copyright (c) 2007 Nicolas Joly
  * Copyright (c) 2007 Paul Goyette
  * Copyright (c) 2007 Tobias Nygren
+ * Copyright (c) 2015 Michael van Elst
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -32,10 +33,14 @@
 
 /*
  * Serial Presence Detect (SPD) memory identification
+ *
+ * JEDEC standard No. 21-C
+ * JEDEC document 4_01_06R24
+ * - Definitions of the EE1004-v 4 Kbit Serial Presence Detect EEPROM [...]
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: spdmem_i2c.c,v 1.10 2015/03/07 14:16:51 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: spdmem_i2c.c,v 1.11 2015/12/07 09:41:37 mlelstv Exp $");
 
 #include <sys/param.h>
 #include <sys/device.h>
@@ -49,13 +54,38 @@
 #include <dev/ic/spdmemvar.h>
 
 /* Constants for matching i2c bus address */
-#define SPDMEM_I2C_ADDRMASK 0x3f8
+#define SPDMEM_I2C_ADDRMASK 0xfff8
 #define SPDMEM_I2C_ADDR     0x50
+#define SPDCTL_I2C_ADDR     0x30
+
+/* set write protection */
+#define SPDCTL_SWP0         (SPDCTL_I2C_ADDR + 1)
+#define SPDCTL_SWP1         (SPDCTL_I2C_ADDR + 4)
+#define SPDCTL_SWP2         (SPDCTL_I2C_ADDR + 5)
+#define SPDCTL_SWP3         (SPDCTL_I2C_ADDR + 0)
+
+/* clear write protections */
+#define SPDCTL_CWP          (SPDCTL_I2C_ADDR + 3)
+
+/* read protection status */
+#define SPDCTL_RPS0         (SPDCTL_I2C_ADDR + 1)
+#define SPDCTL_RPS1         (SPDCTL_I2C_ADDR + 4)
+#define SPDCTL_RPS2         (SPDCTL_I2C_ADDR + 5)
+#define SPDCTL_RPS3         (SPDCTL_I2C_ADDR + 0)
+
+/* select page address */
+#define SPDCTL_SPA0         (SPDCTL_I2C_ADDR + 6)
+#define SPDCTL_SPA1         (SPDCTL_I2C_ADDR + 7)
+
+/* read page address */
+#define SPDCTL_RPA          (SPDCTL_I2C_ADDR + 6)
 
 struct spdmem_i2c_softc {
        struct spdmem_softc sc_base;
        i2c_tag_t sc_tag;
-       i2c_addr_t sc_addr;
+       i2c_addr_t sc_addr; /* EEPROM */
+       i2c_addr_t sc_page0;
+       i2c_addr_t sc_page1;
 };
 
 static int  spdmem_i2c_match(device_t, cfdata_t, void *);
@@ -65,7 +95,7 @@
 CFATTACH_DECL_NEW(spdmem_iic, sizeof(struct spdmem_i2c_softc),
     spdmem_i2c_match, spdmem_i2c_attach, spdmem_i2c_detach, NULL);
 
-static uint8_t spdmem_i2c_read(struct spdmem_softc *, uint8_t);
+static uint8_t spdmem_i2c_read(struct spdmem_softc *, uint16_t);
 
 static int
 spdmem_i2c_match(device_t parent, cfdata_t match, void *aux)
@@ -88,6 +118,8 @@
 
        sc.sc_tag = ia->ia_tag;
        sc.sc_addr = ia->ia_addr;
+       sc.sc_page0 = SPDCTL_SPA0;
+       sc.sc_page1 = SPDCTL_SPA1;
        sc.sc_base.sc_read = spdmem_i2c_read;
 
        return spdmem_common_probe(&sc.sc_base);
@@ -101,6 +133,8 @@
 
        sc->sc_tag = ia->ia_tag;
        sc->sc_addr = ia->ia_addr;
+       sc->sc_page0 = SPDCTL_SPA0;
+       sc->sc_page1 = SPDCTL_SPA1;
        sc->sc_base.sc_read = spdmem_i2c_read;
 
        if (!pmf_device_register(self, NULL, NULL))
@@ -120,14 +154,28 @@
 }
 
 static uint8_t
-spdmem_i2c_read(struct spdmem_softc *softc, uint8_t reg)
+spdmem_i2c_read(struct spdmem_softc *softc, uint16_t addr)
 {
-       uint8_t val;
+       uint8_t reg, val;
        struct spdmem_i2c_softc *sc = (struct spdmem_i2c_softc *)softc;
+       static uint8_t dummy = 0;
+
+       reg = addr & 0xff;
 
        iic_acquire_bus(sc->sc_tag, 0);
-       iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, &reg, 1,
-                &val, 1, I2C_F_POLL);
+
+       if (addr & 0x100) {
+               iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_page1,
+                       &dummy, 1, NULL, 0, I2C_F_POLL);
+               iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
+                       &reg, 1, &val, 1, I2C_F_POLL);
+               iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_page0,
+                       &dummy, 1, NULL, 0, I2C_F_POLL);
+       } else {
+               iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
+                       &reg, 1, &val, 1, I2C_F_POLL);
+       }
+
        iic_release_bus(sc->sc_tag, 0);
 
        return val;
diff -r 191e785e47c5 -r 8d380dabc57b sys/dev/ic/spdmemvar.h
--- a/sys/dev/ic/spdmemvar.h    Mon Dec 07 06:28:22 2015 +0000
+++ b/sys/dev/ic/spdmemvar.h    Mon Dec 07 09:41:37 2015 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: spdmemvar.h,v 1.8 2015/12/06 09:31:20 msaitoh Exp $ */
+/* $NetBSD: spdmemvar.h,v 1.9 2015/12/07 09:41:37 mlelstv Exp $ */
 
 /*
  * Copyright (c) 2007 Paul Goyette
@@ -885,7 +885,7 @@
 #define SPDMEM_TYPE_MAXLEN 24
 
 struct spdmem_softc {
-       uint8_t         (*sc_read)(struct spdmem_softc *, uint8_t);
+       uint8_t         (*sc_read)(struct spdmem_softc *, uint16_t);
        struct spdmem   sc_spd_data;
        struct sysctllog *sc_sysctl_log;
        char            sc_type[SPDMEM_TYPE_MAXLEN];