[PATCH 0/6] SPD EEPROM improvements

[PATCH 0/6] SPD EEPROM improvements

[Sascha Hauer]

This series adds the SPD EEPROM definitions for DDR4, also we get a
function to read SPD EEPROMs in the PBL, using the early i.MX I2C driver
added in another series in "[PATCH 10/10] i2c: i.MX: Add early driver for use in PBL"

Sascha

Sascha Hauer (6):
  crc: import crc_itu_t() from kernel
  crc: Add PBL variant for crc_itu_t()
  ddr_spd: Update from U-Boot
  ddr_spd: Add function to read eeprom
  ddr_spd: provide common SPD type
  ddr_spd: Enable in PBL

 arch/ppc/ddr-8xxx/ddr2_dimm_params.c |   6 +-
 arch/ppc/ddr-8xxx/ddr3_dimm_params.c |  10 +-
 arch/ppc/include/asm/fsl_ddr_sdram.h |   4 +-
 commands/Kconfig                     |   2 +-
 common/Kconfig                       |   2 +-
 common/Makefile                      |   2 +-
 common/ddr_spd.c                     | 203 +++++++-
 common/ratp/Kconfig                  |   2 +-
 crypto/Kconfig                       |   3 +-
 crypto/Makefile                      |   2 +-
 crypto/crc-itu-t.c                   |  60 +++
 crypto/crc16.c                       | 103 ----
 drivers/mci/Kconfig                  |   2 +-
 drivers/mci/mci_spi.c                |   4 +-
 include/crc.h                        |  32 +-
 include/ddr_spd.h                    | 695 ++++++++++++++++++++-------
 lib/Kconfig                          |   4 +-
 lib/ratp.c                           |   4 +-
 lib/xymodem.c                        |   2 +-
 19 files changed, 805 insertions(+), 337 deletions(-)
 create mode 100644 crypto/crc-itu-t.c
 delete mode 100644 crypto/crc16.c

-- 
2.20.1


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[PATCH 1/6] crc: import crc_itu_t() from kernel

[Sascha Hauer]

Out cyc_crc16() function is the same function as crc_itu_t() in the
Linux kernel. Import and use crc_itu_t() from the Kernel for
consistency.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 commands/Kconfig      |   2 +-
 common/Kconfig        |   2 +-
 common/ddr_spd.c      |   2 +-
 common/ratp/Kconfig   |   2 +-
 crypto/Kconfig        |   3 +-
 crypto/Makefile       |   2 +-
 crypto/crc-itu-t.c    |  60 ++++++++++++++++++++++++
 crypto/crc16.c        | 103 ------------------------------------------
 drivers/mci/Kconfig   |   2 +-
 drivers/mci/mci_spi.c |   4 +-
 include/crc.h         |  16 ++++++-
 lib/Kconfig           |   4 +-
 lib/ratp.c            |   4 +-
 lib/xymodem.c         |   2 +-
 14 files changed, 88 insertions(+), 120 deletions(-)
 create mode 100644 crypto/crc-itu-t.c
 delete mode 100644 crypto/crc16.c

diff --git a/commands/Kconfig b/commands/Kconfig
index c14332c9d7..4f5d84ac18 100644
--- a/commands/Kconfig
+++ b/commands/Kconfig
@@ -394,7 +394,7 @@ config CMD_GO
 
 config CMD_LOADB
 	depends on CONSOLE_FULL
-	select CRC16
+	select CRC_ITU_T
 	tristate
 	prompt "loadb"
 	help
diff --git a/common/Kconfig b/common/Kconfig
index 21b33f06f7..749bdcf271 100644
--- a/common/Kconfig
+++ b/common/Kconfig
@@ -1229,4 +1229,4 @@ config HAS_DEBUG_LL
 
 config DDR_SPD
 	bool
-	select CRC16
+	select CRC_ITU_T
diff --git a/common/ddr_spd.c b/common/ddr_spd.c
index 7e2945ed96..2110972f5b 100644
--- a/common/ddr_spd.c
+++ b/common/ddr_spd.c
@@ -51,7 +51,7 @@ uint32_t ddr3_spd_checksum_pass(const struct ddr3_spd_eeprom_s *spd)
 	 */
 
 	len = !(spd->info_size_crc & 0x80) ? 126 : 117;
-	csum16 = cyg_crc16((char *)spd, len);
+	csum16 = crc_itu_t(0, (char *)spd, len);
 
 	crc_lsb = (char) (csum16 & 0xff);
 	crc_msb = (char) (csum16 >> 8);
diff --git a/common/ratp/Kconfig b/common/ratp/Kconfig
index 25c931b978..30462c6c97 100644
--- a/common/ratp/Kconfig
+++ b/common/ratp/Kconfig
@@ -2,7 +2,7 @@
 config CONSOLE_RATP
 	bool
 	select RATP
-	select CRC16
+	select CRC_ITU_T
 	select POLLER
 	select CMDLINE_EDITING
 	depends on CONSOLE_FULL
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 6d65c24d4f..c06d3c054e 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -3,8 +3,7 @@ menu "Crypto support"
 config CRC32
 	bool
 
-config CRC16
-	default y
+config CRC_ITU_T
 	bool
 
 config CRC7
diff --git a/crypto/Makefile b/crypto/Makefile
index a7240d1d6e..0014b0f4ce 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -1,5 +1,5 @@
 obj-$(CONFIG_CRC32)	+= crc32.o
-obj-$(CONFIG_CRC16)	+= crc16.o
+obj-$(CONFIG_CRC_ITU_T)	+= crc-itu-t.o
 obj-$(CONFIG_CRC7)	+= crc7.o
 obj-$(CONFIG_DIGEST)	+= digest.o
 obj-$(CONFIG_DIGEST_CRC32_GENERIC)	+= crc32_digest.o
diff --git a/crypto/crc-itu-t.c b/crypto/crc-itu-t.c
new file mode 100644
index 0000000000..64bccfb742
--- /dev/null
+++ b/crypto/crc-itu-t.c
@@ -0,0 +1,60 @@
+/*
+ *      crc-itu-t.c
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include <crc.h>
+
+/** CRC table for the CRC ITU-T V.41 0x1021 (x^16 + x^12 + x^15 + 1) */
+const u16 crc_itu_t_table[256] = {
+	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
+	0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
+	0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
+	0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
+	0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
+	0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
+	0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
+	0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
+	0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
+	0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
+	0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
+	0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
+	0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
+	0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
+	0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
+	0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
+	0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
+	0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
+	0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
+	0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
+	0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
+	0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
+	0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
+	0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
+	0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
+	0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
+	0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
+	0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
+	0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
+	0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
+	0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
+	0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
+};
+
+/**
+ * crc_itu_t - Compute the CRC-ITU-T for the data buffer
+ *
+ * @crc:     previous CRC value
+ * @buffer:  data pointer
+ * @len:     number of bytes in the buffer
+ *
+ * Returns the updated CRC value
+ */
+u16 crc_itu_t(u16 crc, const u8 *buffer, size_t len)
+{
+	while (len--)
+		crc = crc_itu_t_byte(crc, *buffer++);
+	return crc;
+}
diff --git a/crypto/crc16.c b/crypto/crc16.c
deleted file mode 100644
index 0b08e9ccde..0000000000
--- a/crypto/crc16.c
+++ /dev/null
@@ -1,103 +0,0 @@
-/*
- *==========================================================================
- *
- *      crc16.c
- *
- *      16 bit CRC with polynomial x^16+x^12+x^5+1
- *
- *==========================================================================
- *####ECOSGPLCOPYRIGHTBEGIN####
- * -------------------------------------------
- * This file is part of eCos, the Embedded Configurable Operating System.
- * Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
- * Copyright (C) 2002 Gary Thomas
- *
- * eCos is free software; you can redistribute it and/or modify it under
- * the terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 2 or (at your option) any later version.
- *
- * eCos is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * for more details.
- *
- * As a special exception, if other files instantiate templates or use macros
- * or inline functions from this file, or you compile this file and link it
- * with other works to produce a work based on this file, this file does not
- * by itself cause the resulting work to be covered by the GNU General Public
- * License. However the source code for this file must still be made available
- * in accordance with section (3) of the GNU General Public License.
- *
- * This exception does not invalidate any other reasons why a work based on
- * this file might be covered by the GNU General Public License.
- *
- * Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
- * at http: *sources.redhat.com/ecos/ecos-license/
- * -------------------------------------------
- *####ECOSGPLCOPYRIGHTEND####
- *==========================================================================
- *#####DESCRIPTIONBEGIN####
- *
- * Author(s):    gthomas
- * Contributors: gthomas,asl
- * Date:         2001-01-31
- * Purpose:
- * Description:
- *
- * This code is part of eCos (tm).
- *
- *####DESCRIPTIONEND####
- *
- *==========================================================================
- */
-
-#include "crc.h"
-
-/* Table of CRC constants - implements x^16+x^12+x^5+1 */
-static const uint16_t crc16_tab[] = {
-    0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
-    0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
-    0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
-    0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
-    0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
-    0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
-    0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
-    0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
-    0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
-    0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
-    0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
-    0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
-    0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
-    0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
-    0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
-    0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
-    0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
-    0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
-    0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
-    0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
-    0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
-    0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
-    0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
-    0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
-    0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
-    0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
-    0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
-    0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
-    0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
-    0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
-    0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
-    0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
-};
-
-uint16_t
-cyg_crc16(const unsigned char *buf, int len)
-{
-    int i;
-    uint16_t cksum;
-
-    cksum = 0;
-    for (i = 0;  i < len;  i++) {
-	cksum = crc16_tab[((cksum>>8) ^ *buf++) & 0xFF] ^ (cksum << 8);
-    }
-    return cksum;
-}
diff --git a/drivers/mci/Kconfig b/drivers/mci/Kconfig
index 2075151d67..397dcf1377 100644
--- a/drivers/mci/Kconfig
+++ b/drivers/mci/Kconfig
@@ -141,7 +141,7 @@ config MCI_SPI
 
 config MMC_SPI_CRC_ON
 	bool "Enable CRC protection for transfers"
-	select CRC16
+	select CRC_ITU_T
 	depends on MCI_SPI
 	help
 	  Enable CRC protection for transfers
diff --git a/drivers/mci/mci_spi.c b/drivers/mci/mci_spi.c
index 011947c8c1..42072da58a 100644
--- a/drivers/mci/mci_spi.c
+++ b/drivers/mci/mci_spi.c
@@ -166,7 +166,7 @@ static uint mmc_spi_readdata(struct mmc_spi_host *host, void *xbuf,
 			mmc_spi_readbytes(host, bsize, buf);
 			mmc_spi_readbytes(host, 2, &crc);
 #ifdef CONFIG_MMC_SPI_CRC_ON
-			if (be16_to_cpu(cyg_crc16(buf, bsize)) != crc) {
+			if (be16_to_cpu(crc_itu_t(0, buf, bsize)) != crc) {
 				dev_dbg(host->dev, "%s: CRC error\n", __func__);
 				r1 = R1_SPI_COM_CRC;
 				break;
@@ -197,7 +197,7 @@ static uint mmc_spi_writedata(struct mmc_spi_host *host, const void *xbuf,
 
 	while (bcnt--) {
 #ifdef CONFIG_MMC_SPI_CRC_ON
-		crc = be16_to_cpu(cyg_crc16((u8 *)buf, bsize));
+		crc = be16_to_cpu(crc_itu_t(0, (u8 *)buf, bsize));
 #endif
 		mmc_spi_writebytes(host, 2, tok);
 		mmc_spi_writebytes(host, bsize, (void *)buf);
diff --git a/include/crc.h b/include/crc.h
index 847a0a4b64..317f6f5494 100644
--- a/include/crc.h
+++ b/include/crc.h
@@ -3,8 +3,20 @@
 
 #include <linux/types.h>
 
-/* 16 bit CRC with polynomial x^16+x^12+x^5+1 */
-extern uint16_t cyg_crc16(const unsigned char *s, int len);
+/*
+ * Implements the standard CRC ITU-T V.41:
+ *   Width 16
+ *   Poly  0x1021 (x^16 + x^12 + x^15 + 1)
+ *   Init  0
+ */
+extern u16 const crc_itu_t_table[256];
+
+extern u16 crc_itu_t(u16 crc, const u8 *buffer, size_t len);
+
+static inline u16 crc_itu_t_byte(u16 crc, const u8 data)
+{
+	return (crc << 8) ^ crc_itu_t_table[((crc >> 8) ^ data) & 0xff];
+}
 
 uint32_t crc32(uint32_t, const void *, unsigned int);
 uint32_t crc32_no_comp(uint32_t, const void *, unsigned int);
diff --git a/lib/Kconfig b/lib/Kconfig
index e048aded8b..ecf578a34e 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -79,7 +79,7 @@ config QSORT
 
 config XYMODEM
 	bool
-	select CRC16
+	select CRC_ITU_T
 
 config LIBSCAN
 	bool
@@ -94,7 +94,7 @@ config STMP_DEVICE
 	bool
 
 config RATP
-	select CRC16
+	select CRC_ITU_T
 	bool "RATP protocol support"
 	help
 	  Reliable Asynchronous Transfer Protocol (RATP) is a protocol for reliably
diff --git a/lib/ratp.c b/lib/ratp.c
index 7801cae519..8167c5bd4c 100644
--- a/lib/ratp.c
+++ b/lib/ratp.c
@@ -315,7 +315,7 @@ static int ratp_recv_pkt_data(struct ratp_internal *ri, void *data, uint8_t len,
 			return ret;
 	}
 
-	crc_expect = cyg_crc16(data, len);
+	crc_expect = crc_itu_t(0, data, len);
 
 	crc_read = get_unaligned_be16(data + len);
 
@@ -419,7 +419,7 @@ static int ratp_send_next_data(struct ratp_internal *ri)
 	pktlen = sizeof(struct ratp_header);
 	if (len > 1) {
 		pktlen += len + 2;
-		crc = cyg_crc16(data, len);
+		crc = crc_itu_t(0, data, len);
 		put_unaligned_be16(crc, data + len);
 	} else if (len == 1) {
 		control |= RATP_CONTROL_SO;
diff --git a/lib/xymodem.c b/lib/xymodem.c
index 9e4ce58b60..136741ab4a 100644
--- a/lib/xymodem.c
+++ b/lib/xymodem.c
@@ -210,7 +210,7 @@ static int check_crc(unsigned char *buf, int len, int crc, int crc_mode)
 			crc8 += buf[i];
 		return crc8 == crc ? 0 : -EBADMSG;
 	case CRC_CRC16:
-		crc16 = cyg_crc16(buf, len);
+		crc16 = crc_itu_t(0, buf, len);
 		xy_dbg("crc16: received = %x, calculated=%x\n", crc, crc16);
 		return crc16 == crc ? 0 : -EBADMSG;
 	case CRC_NONE:
-- 
2.20.1


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[PATCH 2/6] crc: Add PBL variant for crc_itu_t()

[Sascha Hauer]

Enable crc_itu_t() for PBL. For the PBL use the slower-but-smaller
variant without table.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 crypto/Makefile |  2 +-
 include/crc.h   | 16 ++++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/crypto/Makefile b/crypto/Makefile
index 0014b0f4ce..3402f57255 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -1,5 +1,5 @@
 obj-$(CONFIG_CRC32)	+= crc32.o
-obj-$(CONFIG_CRC_ITU_T)	+= crc-itu-t.o
+obj-pbl-$(CONFIG_CRC_ITU_T)	+= crc-itu-t.o
 obj-$(CONFIG_CRC7)	+= crc7.o
 obj-$(CONFIG_DIGEST)	+= digest.o
 obj-$(CONFIG_DIGEST_CRC32_GENERIC)	+= crc32_digest.o
diff --git a/include/crc.h b/include/crc.h
index 317f6f5494..a67388f732 100644
--- a/include/crc.h
+++ b/include/crc.h
@@ -13,10 +13,26 @@ extern u16 const crc_itu_t_table[256];
 
 extern u16 crc_itu_t(u16 crc, const u8 *buffer, size_t len);
 
+#ifdef __PBL__
+static inline u16 crc_itu_t_byte(u16 crc, const u8 data)
+{
+	int i;
+
+	crc = crc ^ data << 8;
+	for (i = 0; i < 8; ++i) {
+		if (crc & 0x8000)
+			crc = crc << 1 ^ 0x1021;
+		else
+			crc = crc << 1;
+	}
+	return crc;
+}
+#else
 static inline u16 crc_itu_t_byte(u16 crc, const u8 data)
 {
 	return (crc << 8) ^ crc_itu_t_table[((crc >> 8) ^ data) & 0xff];
 }
+#endif
 
 uint32_t crc32(uint32_t, const void *, unsigned int);
 uint32_t crc32_no_comp(uint32_t, const void *, unsigned int);
-- 
2.20.1


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[PATCH 3/6] ddr_spd: Update from U-Boot

[Sascha Hauer]

This updates the ddr_spd.h header file from U-Boot-2019.01 with some
small changes:

- typedefs are removed
- "_s" suffix from struct types removed
- remove unnecessary "extern" from function declarations

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 arch/ppc/ddr-8xxx/ddr2_dimm_params.c |   6 +-
 arch/ppc/ddr-8xxx/ddr3_dimm_params.c |  10 +-
 arch/ppc/include/asm/fsl_ddr_sdram.h |   4 +-
 common/ddr_spd.c                     | 122 ++++-
 include/ddr_spd.h                    | 679 +++++++++++++++++++--------
 5 files changed, 604 insertions(+), 217 deletions(-)

diff --git a/arch/ppc/ddr-8xxx/ddr2_dimm_params.c b/arch/ppc/ddr-8xxx/ddr2_dimm_params.c
index cc7f3fa6ba..22c05ca6da 100644
--- a/arch/ppc/ddr-8xxx/ddr2_dimm_params.c
+++ b/arch/ppc/ddr-8xxx/ddr2_dimm_params.c
@@ -190,13 +190,13 @@ uint32_t
 compute_dimm_parameters(const generic_spd_eeprom_t *spdin,
 		struct dimm_params_s *pdimm)
 {
-	const struct ddr2_spd_eeprom_s *spd = spdin;
-	uint32_t retval;
+	const struct ddr2_spd_eeprom *spd = spdin;
+	int retval;
 
 	if (spd->mem_type != SPD_MEMTYPE_DDR2)
 		goto error;
 
-	retval = ddr2_spd_checksum_pass(spd);
+	retval = ddr2_spd_check(spd);
 	if (retval)
 		goto error;
 
diff --git a/arch/ppc/ddr-8xxx/ddr3_dimm_params.c b/arch/ppc/ddr-8xxx/ddr3_dimm_params.c
index d510c5b265..4f44925ab9 100644
--- a/arch/ppc/ddr-8xxx/ddr3_dimm_params.c
+++ b/arch/ppc/ddr-8xxx/ddr3_dimm_params.c
@@ -50,7 +50,7 @@
  *	010		16bits
  *	011		32bits
  */
-static uint64_t compute_ranksize(const struct ddr3_spd_eeprom_s *spd)
+static uint64_t compute_ranksize(const struct ddr3_spd_eeprom *spd)
 {
 	uint64_t bsize;
 	int sdram_cap_bsize = 0, prim_bus_width = 0, sdram_width = 0;
@@ -78,14 +78,14 @@ uint32_t
 compute_dimm_parameters(const generic_spd_eeprom_t *spdin,
 		struct dimm_params_s *pdimm)
 {
-	const struct ddr3_spd_eeprom_s *spd = spdin;
-	uint32_t retval, mtb_ps;
-	int ftb_tmp;
+	const struct ddr3_spd_eeprom *spd = spdin;
+	uint32_t mtb_ps;
+	int retval, ftb_tmp;
 
 	if (spd->mem_type != SPD_MEMTYPE_DDR3)
 		goto error;
 
-	retval = ddr3_spd_checksum_pass(spd);
+	retval = ddr3_spd_check(spd);
 	if (retval)
 		goto error;
 
diff --git a/arch/ppc/include/asm/fsl_ddr_sdram.h b/arch/ppc/include/asm/fsl_ddr_sdram.h
index 2c45608e5d..f4732389f6 100644
--- a/arch/ppc/include/asm/fsl_ddr_sdram.h
+++ b/arch/ppc/include/asm/fsl_ddr_sdram.h
@@ -32,10 +32,10 @@
 
 #define FSL_DDR_MIN_TCKE_PULSE_WIDTH_DDR	(3)
 #if defined(CONFIG_FSL_DDR2)
-typedef struct ddr2_spd_eeprom_s generic_spd_eeprom_t;
+typedef struct ddr2_spd_eeprom generic_spd_eeprom_t;
 #define FSL_SDRAM_TYPE	SDRAM_TYPE_DDR2
 #elif defined(CONFIG_FSL_DDR3)
-typedef struct ddr3_spd_eeprom_s generic_spd_eeprom_t;
+typedef struct ddr3_spd_eeprom generic_spd_eeprom_t;
 #define FSL_SDRAM_TYPE	SDRAM_TYPE_DDR3
 #endif
 
diff --git a/common/ddr_spd.c b/common/ddr_spd.c
index 2110972f5b..9394c57fa3 100644
--- a/common/ddr_spd.c
+++ b/common/ddr_spd.c
@@ -10,39 +10,65 @@
 #include <crc.h>
 #include <ddr_spd.h>
 
-uint32_t ddr2_spd_checksum_pass(const struct ddr2_spd_eeprom_s *spd)
+/* used for ddr1 and ddr2 spd */
+static int spd_check(const u8 *buf, u8 spd_rev, u8 spd_cksum)
 {
-	uint32_t i, cksum = 0;
-	const uint8_t *buf = (const uint8_t *)spd;
-	uint8_t rev, spd_cksum;
+	unsigned int cksum = 0;
+	unsigned int i;
 
-	rev = spd->spd_rev;
-	spd_cksum = spd->cksum;
-
-	/* Rev 1.X or less supported by this code */
-	if (rev >= 0x20)
-		goto error;
+	/*
+	 * Check SPD revision supported
+	 * Rev 1.X or less supported by this code
+	 */
+	if (spd_rev >= 0x20) {
+		printf("SPD revision %02X not supported by this code\n",
+		       spd_rev);
+		return 1;
+	}
+	if (spd_rev > 0x13) {
+		printf("SPD revision %02X not verified by this code\n",
+		       spd_rev);
+	}
 
 	/*
-	 * The checksum is calculated on the first 64 bytes
-	 * of the SPD as per JEDEC specification.
+	 * Calculate checksum
 	 */
 	for (i = 0; i < 63; i++)
 		cksum += *buf++;
+
 	cksum &= 0xFF;
 
-	if (cksum != spd_cksum)
-		goto error;
+	if (cksum != spd_cksum) {
+		printf("SPD checksum unexpected. "
+			"Checksum in SPD = %02X, computed SPD = %02X\n",
+			spd_cksum, cksum);
+		return -EBADMSG;
+	}
 
 	return 0;
-error:
-	return 1;
 }
 
-uint32_t ddr3_spd_checksum_pass(const struct ddr3_spd_eeprom_s *spd)
+int ddr1_spd_check(const struct ddr1_spd_eeprom *spd)
 {
-	char crc_lsb, crc_msb;
-	int csum16, len;
+	const u8 *p = (const u8 *)spd;
+
+	return spd_check(p, spd->spd_rev, spd->cksum);
+}
+
+int ddr2_spd_check(const struct ddr2_spd_eeprom *spd)
+{
+	const u8 *p = (const u8 *)spd;
+
+	return spd_check(p, spd->spd_rev, spd->cksum);
+}
+
+int ddr3_spd_check(const struct ddr3_spd_eeprom *spd)
+{
+	char *p = (char *)spd;
+	int csum16;
+	int len;
+	char crc_lsb;	/* byte 126 */
+	char crc_msb;	/* byte 127 */
 
 	/*
 	 * SPD byte0[7] - CRC coverage
@@ -51,13 +77,61 @@ uint32_t ddr3_spd_checksum_pass(const struct ddr3_spd_eeprom_s *spd)
 	 */
 
 	len = !(spd->info_size_crc & 0x80) ? 126 : 117;
-	csum16 = crc_itu_t(0, (char *)spd, len);
+	csum16 = crc_itu_t(0, p, len);
 
 	crc_lsb = (char) (csum16 & 0xff);
 	crc_msb = (char) (csum16 >> 8);
 
-	if (spd->crc[0] != crc_lsb || spd->crc[1] != crc_msb)
-		return 1;
+	if (spd->crc[0] == crc_lsb && spd->crc[1] == crc_msb) {
+		return 0;
+	} else {
+		printf("SPD checksum unexpected.\n"
+			"Checksum lsb in SPD = %02X, computed SPD = %02X\n"
+			"Checksum msb in SPD = %02X, computed SPD = %02X\n",
+			spd->crc[0], crc_lsb, spd->crc[1], crc_msb);
+		return -EBADMSG;
+	}
+}
+
+int ddr4_spd_check(const struct ddr4_spd_eeprom *spd)
+{
+	char *p = (char *)spd;
+	int csum16;
+	int len;
+	char crc_lsb;	/* byte 126 */
+	char crc_msb;	/* byte 127 */
+
+	len = 126;
+	csum16 = crc_itu_t(0, p, len);
+
+	crc_lsb = (char) (csum16 & 0xff);
+	crc_msb = (char) (csum16 >> 8);
+
+	if (spd->crc[0] != crc_lsb || spd->crc[1] != crc_msb) {
+		printf("SPD checksum unexpected.\n"
+			"Checksum lsb in SPD = %02X, computed SPD = %02X\n"
+			"Checksum msb in SPD = %02X, computed SPD = %02X\n",
+			spd->crc[0], crc_lsb, spd->crc[1], crc_msb);
+		return -EBADMSG;
+	}
+
+	p = (char *)((ulong)spd + 128);
+	len = 126;
+	csum16 = crc_itu_t(0, p, len);
+
+	crc_lsb = (char) (csum16 & 0xff);
+	crc_msb = (char) (csum16 >> 8);
+
+	if (spd->mod_section.uc[126] != crc_lsb ||
+	    spd->mod_section.uc[127] != crc_msb) {
+		printf("SPD checksum unexpected.\n"
+			"Checksum lsb in SPD = %02X, computed SPD = %02X\n"
+			"Checksum msb in SPD = %02X, computed SPD = %02X\n",
+			spd->mod_section.uc[126],
+			crc_lsb, spd->mod_section.uc[127],
+			crc_msb);
+		return -EBADMSG;
+	}
 
 	return 0;
 }
@@ -172,7 +246,7 @@ void ddr_spd_print(uint8_t *record)
 	int ctime;
 	uint8_t parity;
 	char *ref, *sum;
-	struct ddr2_spd_eeprom_s *s = (struct ddr2_spd_eeprom_s *)record;
+	struct ddr2_spd_eeprom *s = (struct ddr2_spd_eeprom *)record;
 
 	if (s->mem_type != SPD_MEMTYPE_DDR2) {
 		printf("Can't dump information for non-DDR2 memory\n");
@@ -201,7 +275,7 @@ void ddr_spd_print(uint8_t *record)
 		}
 	}
 
-	if (ddr2_spd_checksum_pass(s))
+	if (ddr2_spd_check(s))
 		sum = "ERR";
 	else
 		sum = "OK";
diff --git a/include/ddr_spd.h b/include/ddr_spd.h
index 01fe73c615..051275141f 100644
--- a/include/ddr_spd.h
+++ b/include/ddr_spd.h
@@ -1,242 +1,520 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
- * Copyright 2008 Freescale Semiconductor, Inc.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * Version 2 as published by the Free Software Foundation.
+ * Copyright 2008-2014 Freescale Semiconductor, Inc.
  */
 
 #ifndef _DDR_SPD_H_
 #define _DDR_SPD_H_
 
+/*
+ * Format from "JEDEC Standard No. 21-C,
+ * Appendix D: Rev 1.0: SPD's for DDR SDRAM
+ */
+struct ddr1_spd_eeprom {
+	unsigned char info_size;   /*  0 # bytes written into serial memory */
+	unsigned char chip_size;   /*  1 Total # bytes of SPD memory device */
+	unsigned char mem_type;    /*  2 Fundamental memory type */
+	unsigned char nrow_addr;   /*  3 # of Row Addresses on this assembly */
+	unsigned char ncol_addr;   /*  4 # of Column Addrs on this assembly */
+	unsigned char nrows;       /*  5 Number of DIMM Banks */
+	unsigned char dataw_lsb;   /*  6 Data Width of this assembly */
+	unsigned char dataw_msb;   /*  7 ... Data Width continuation */
+	unsigned char voltage;     /*  8 Voltage intf std of this assembly */
+	unsigned char clk_cycle;   /*  9 SDRAM Cycle time @ CL=X */
+	unsigned char clk_access;  /* 10 SDRAM Access from Clk @ CL=X (tAC) */
+	unsigned char config;      /* 11 DIMM Configuration type */
+	unsigned char refresh;     /* 12 Refresh Rate/Type */
+	unsigned char primw;       /* 13 Primary SDRAM Width */
+	unsigned char ecw;         /* 14 Error Checking SDRAM width */
+	unsigned char min_delay;   /* 15 for Back to Back Random Address */
+	unsigned char burstl;      /* 16 Burst Lengths Supported */
+	unsigned char nbanks;      /* 17 # of Banks on SDRAM Device */
+	unsigned char cas_lat;     /* 18 CAS# Latencies Supported */
+	unsigned char cs_lat;      /* 19 CS# Latency */
+	unsigned char write_lat;   /* 20 Write Latency (aka Write Recovery) */
+	unsigned char mod_attr;    /* 21 SDRAM Module Attributes */
+	unsigned char dev_attr;    /* 22 SDRAM Device Attributes */
+	unsigned char clk_cycle2;  /* 23 Min SDRAM Cycle time @ CL=X-0.5 */
+	unsigned char clk_access2; /* 24 SDRAM Access from
+					 Clk @ CL=X-0.5 (tAC) */
+	unsigned char clk_cycle3;  /* 25 Min SDRAM Cycle time @ CL=X-1 */
+	unsigned char clk_access3; /* 26 Max Access from Clk @ CL=X-1 (tAC) */
+	unsigned char trp;         /* 27 Min Row Precharge Time (tRP)*/
+	unsigned char trrd;        /* 28 Min Row Active to Row Active (tRRD) */
+	unsigned char trcd;        /* 29 Min RAS to CAS Delay (tRCD) */
+	unsigned char tras;        /* 30 Minimum RAS Pulse Width (tRAS) */
+	unsigned char bank_dens;   /* 31 Density of each bank on module */
+	unsigned char ca_setup;    /* 32 Addr + Cmd Setup Time Before Clk */
+	unsigned char ca_hold;     /* 33 Addr + Cmd Hold Time After Clk */
+	unsigned char data_setup;  /* 34 Data Input Setup Time Before Strobe */
+	unsigned char data_hold;   /* 35 Data Input Hold Time After Strobe */
+	unsigned char res_36_40[5];/* 36-40 reserved for VCSDRAM */
+	unsigned char trc;         /* 41 Min Active to Auto refresh time tRC */
+	unsigned char trfc;        /* 42 Min Auto to Active period tRFC */
+	unsigned char tckmax;      /* 43 Max device cycle time tCKmax */
+	unsigned char tdqsq;       /* 44 Max DQS to DQ skew (tDQSQ max) */
+	unsigned char tqhs;        /* 45 Max Read DataHold skew (tQHS) */
+	unsigned char res_46;      /* 46 Reserved */
+	unsigned char dimm_height; /* 47 DDR SDRAM DIMM Height */
+	unsigned char res_48_61[14]; /* 48-61 Reserved */
+	unsigned char spd_rev;     /* 62 SPD Data Revision Code */
+	unsigned char cksum;       /* 63 Checksum for bytes 0-62 */
+	unsigned char mid[8];      /* 64-71 Mfr's JEDEC ID code per JEP-106 */
+	unsigned char mloc;        /* 72 Manufacturing Location */
+	unsigned char mpart[18];   /* 73 Manufacturer's Part Number */
+	unsigned char rev[2];      /* 91 Revision Code */
+	unsigned char mdate[2];    /* 93 Manufacturing Date */
+	unsigned char sernum[4];   /* 95 Assembly Serial Number */
+	unsigned char mspec[27];   /* 99-127 Manufacturer Specific Data */
+
+};
+
 /*
  * Format from "JEDEC Appendix X: Serial Presence Detects for DDR2 SDRAM",
  * SPD Revision 1.2
  */
-struct ddr2_spd_eeprom_s {
-	uint8_t info_size;   /*  0 # bytes written into serial memory */
-	uint8_t chip_size;   /*  1 Total # bytes of SPD memory device */
-	uint8_t mem_type;    /*  2 Fundamental memory type */
-	uint8_t nrow_addr;   /*  3 # of Row Addresses on this assembly */
-	uint8_t ncol_addr;   /*  4 # of Column Addrs on this assembly */
-	uint8_t mod_ranks;   /*  5 Number of DIMM Ranks */
-	uint8_t dataw;       /*  6 Module Data Width */
-	uint8_t res_7;       /*  7 Reserved */
-	uint8_t voltage;     /*  8 Voltage intf std of this assembly */
-	uint8_t clk_cycle;   /*  9 SDRAM Cycle time @ CL=X */
-	uint8_t clk_access;  /* 10 SDRAM Access from Clk @ CL=X (tAC) */
-	uint8_t config;      /* 11 DIMM Configuration type */
-	uint8_t refresh;     /* 12 Refresh Rate/Type */
-	uint8_t primw;       /* 13 Primary SDRAM Width */
-	uint8_t ecw;         /* 14 Error Checking SDRAM width */
-	uint8_t res_15;      /* 15 Reserved */
-	uint8_t burstl;      /* 16 Burst Lengths Supported */
-	uint8_t nbanks;      /* 17 # of Banks on Each SDRAM Device */
-	uint8_t cas_lat;     /* 18 CAS# Latencies Supported */
-	uint8_t mech_char;   /* 19 DIMM Mechanical Characteristics */
-	uint8_t dimm_type;   /* 20 DIMM type information */
-	uint8_t mod_attr;    /* 21 SDRAM Module Attributes */
-	uint8_t dev_attr;    /* 22 SDRAM Device Attributes */
-	uint8_t clk_cycle2;  /* 23 Min SDRAM Cycle time @ CL=X-1 */
-	uint8_t clk_access2; /* 24 SDRAM Access from Clk @ CL=X-1 (tAC) */
-	uint8_t clk_cycle3;  /* 25 Min SDRAM Cycle time @ CL=X-2 */
-	uint8_t clk_access3; /* 26 Max Access from Clk @ CL=X-2 (tAC) */
-	uint8_t trp;         /* 27 Min Row Precharge Time (tRP)*/
-	uint8_t trrd;        /* 28 Min Row Active to Row Active (tRRD) */
-	uint8_t trcd;        /* 29 Min RAS to CAS Delay (tRCD) */
-	uint8_t tras;        /* 30 Minimum RAS Pulse Width (tRAS) */
-	uint8_t rank_dens;   /* 31 Density of each rank on module */
-	uint8_t ca_setup;    /* 32 Addr+Cmd Setup Time Before Clk (tIS) */
-	uint8_t ca_hold;     /* 33 Addr+Cmd Hold Time After Clk (tIH) */
-	uint8_t data_setup;  /* 34 Data Input Setup Time Before Strobe
-					(tDS) */
-	uint8_t data_hold;   /* 35 Data Input Hold Time
-					After Strobe (tDH) */
-	uint8_t twr;         /* 36 Write Recovery time tWR */
-	uint8_t twtr;        /* 37 Int write to read delay tWTR */
-	uint8_t trtp;        /* 38 Int read to precharge delay tRTP */
-	uint8_t mem_probe;   /* 39 Mem analysis probe characteristics */
-	uint8_t trctrfc_ext; /* 40 Extensions to trc and trfc */
-	uint8_t trc;         /* 41 Min Active to Auto refresh time tRC */
-	uint8_t trfc;        /* 42 Min Auto to Active period tRFC */
-	uint8_t tckmax;      /* 43 Max device cycle time tCKmax */
-	uint8_t tdqsq;       /* 44 Max DQS to DQ skew (tDQSQ max) */
-	uint8_t tqhs;        /* 45 Max Read DataHold skew (tQHS) */
-	uint8_t pll_relock;  /* 46 PLL Relock time */
-	uint8_t Tcasemax;    /* 47 Tcasemax */
-	uint8_t psiTAdram;   /* 48 Thermal Resistance of DRAM Package
-					from Top (Case) to Ambient
-					(Psi T-A DRAM) */
-	uint8_t dt0_mode;    /* 49 DRAM Case Temperature Rise from
-					Ambient due to Activate-Precharge/Mode
-					Bits (DT0/Mode Bits) */
-	uint8_t dt2n_dt2q;   /* 50 DRAM Case Temperature Rise from
-					Ambient due to Precharge/Quiet Standby
-					(DT2N/DT2Q) */
-	uint8_t dt2p;        /* 51 DRAM Case Temperature Rise from
-					Ambient due to Precharge Power-Down
-					(DT2P) */
-	uint8_t dt3n;        /* 52 DRAM Case Temperature Rise from
-					Ambient due to Active Standby (DT3N) */
-	uint8_t dt3pfast;    /* 53 DRAM Case Temperature Rise from
-					Ambient due to Active Power-Down with
-					Fast PDN Exit (DT3Pfast) */
-	uint8_t dt3pslow;    /* 54 DRAM Case Temperature Rise from
-					Ambient due to Active Power-Down with
-					Slow PDN Exit (DT3Pslow) */
-	uint8_t dt4r_dt4r4w; /* 55 DRAM Case Temperature Rise from
-					Ambient due to Page Open Burst
-					Read/DT4R4W Mode Bit
-					(DT4R/DT4R4W Mode Bit) */
-	uint8_t dt5b;        /* 56 DRAM Case Temperature Rise from
-					Ambient due to Burst Refresh (DT5B) */
-	uint8_t dt7;         /* 57 DRAM Case Temperature Rise from
-					Ambient due to Bank Interleave Reads
-					with Auto-Precharge (DT7) */
-	uint8_t psiTApll;    /* 58 Thermal Resistance of PLL Package
-					form Top (Case) to Ambient
-					(Psi T-A PLL) */
-	uint8_t psiTAreg;    /* 59 Thermal Reisitance of Register
-					Package from Top (Case) to Ambient
-					(Psi T-A Register) */
-	uint8_t dtpllactive; /* 60 PLL Case Temperature Rise from
-					Ambient due to PLL Active
-					(DT PLL Active) */
-	uint8_t dtregact;    /* 61 Register Case Temperature Rise from
-					Ambient due to Register Active/Mode
-					Bit (DT Register Active/Mode Bit) */
-	uint8_t spd_rev;     /* 62 SPD Data Revision Code */
-	uint8_t cksum;       /* 63 Checksum for bytes 0-62 */
-	uint8_t mid[8];      /* 64 Mfr's JEDEC ID code per JEP-106 */
-	uint8_t mloc;        /* 72 Manufacturing Location */
-	uint8_t mpart[18];   /* 73 Manufacturer's Part Number */
-	uint8_t rev[2];      /* 91 Revision Code */
-	uint8_t mdate[2];    /* 93 Manufacturing Date */
-	uint8_t sernum[4];   /* 95 Assembly Serial Number */
-	uint8_t mspec[27];   /* 99-127 Manufacturer Specific Data */
+struct ddr2_spd_eeprom {
+	unsigned char info_size;   /*  0 # bytes written into serial memory */
+	unsigned char chip_size;   /*  1 Total # bytes of SPD memory device */
+	unsigned char mem_type;    /*  2 Fundamental memory type */
+	unsigned char nrow_addr;   /*  3 # of Row Addresses on this assembly */
+	unsigned char ncol_addr;   /*  4 # of Column Addrs on this assembly */
+	unsigned char mod_ranks;   /*  5 Number of DIMM Ranks */
+	unsigned char dataw;       /*  6 Module Data Width */
+	unsigned char res_7;       /*  7 Reserved */
+	unsigned char voltage;     /*  8 Voltage intf std of this assembly */
+	unsigned char clk_cycle;   /*  9 SDRAM Cycle time @ CL=X */
+	unsigned char clk_access;  /* 10 SDRAM Access from Clk @ CL=X (tAC) */
+	unsigned char config;      /* 11 DIMM Configuration type */
+	unsigned char refresh;     /* 12 Refresh Rate/Type */
+	unsigned char primw;       /* 13 Primary SDRAM Width */
+	unsigned char ecw;         /* 14 Error Checking SDRAM width */
+	unsigned char res_15;      /* 15 Reserved */
+	unsigned char burstl;      /* 16 Burst Lengths Supported */
+	unsigned char nbanks;      /* 17 # of Banks on Each SDRAM Device */
+	unsigned char cas_lat;     /* 18 CAS# Latencies Supported */
+	unsigned char mech_char;   /* 19 DIMM Mechanical Characteristics */
+	unsigned char dimm_type;   /* 20 DIMM type information */
+	unsigned char mod_attr;    /* 21 SDRAM Module Attributes */
+	unsigned char dev_attr;    /* 22 SDRAM Device Attributes */
+	unsigned char clk_cycle2;  /* 23 Min SDRAM Cycle time @ CL=X-1 */
+	unsigned char clk_access2; /* 24 SDRAM Access from Clk @ CL=X-1 (tAC) */
+	unsigned char clk_cycle3;  /* 25 Min SDRAM Cycle time @ CL=X-2 */
+	unsigned char clk_access3; /* 26 Max Access from Clk @ CL=X-2 (tAC) */
+	unsigned char trp;         /* 27 Min Row Precharge Time (tRP)*/
+	unsigned char trrd;        /* 28 Min Row Active to Row Active (tRRD) */
+	unsigned char trcd;        /* 29 Min RAS to CAS Delay (tRCD) */
+	unsigned char tras;        /* 30 Minimum RAS Pulse Width (tRAS) */
+	unsigned char rank_dens;   /* 31 Density of each rank on module */
+	unsigned char ca_setup;    /* 32 Addr+Cmd Setup Time Before Clk (tIS) */
+	unsigned char ca_hold;     /* 33 Addr+Cmd Hold Time After Clk (tIH) */
+	unsigned char data_setup;  /* 34 Data Input Setup Time
+					 Before Strobe (tDS) */
+	unsigned char data_hold;   /* 35 Data Input Hold Time
+					 After Strobe (tDH) */
+	unsigned char twr;         /* 36 Write Recovery time tWR */
+	unsigned char twtr;        /* 37 Int write to read delay tWTR */
+	unsigned char trtp;        /* 38 Int read to precharge delay tRTP */
+	unsigned char mem_probe;   /* 39 Mem analysis probe characteristics */
+	unsigned char trctrfc_ext; /* 40 Extensions to trc and trfc */
+	unsigned char trc;         /* 41 Min Active to Auto refresh time tRC */
+	unsigned char trfc;        /* 42 Min Auto to Active period tRFC */
+	unsigned char tckmax;      /* 43 Max device cycle time tCKmax */
+	unsigned char tdqsq;       /* 44 Max DQS to DQ skew (tDQSQ max) */
+	unsigned char tqhs;        /* 45 Max Read DataHold skew (tQHS) */
+	unsigned char pll_relock;  /* 46 PLL Relock time */
+	unsigned char t_casemax;    /* 47 Tcasemax */
+	unsigned char psi_ta_dram;  /* 48 Thermal Resistance of DRAM Package from
+					 Top (Case) to Ambient (Psi T-A DRAM) */
+	unsigned char dt0_mode;    /* 49 DRAM Case Temperature Rise from Ambient
+					 due to Activate-Precharge/Mode Bits
+					 (DT0/Mode Bits) */
+	unsigned char dt2n_dt2q;   /* 50 DRAM Case Temperature Rise from Ambient
+					 due to Precharge/Quiet Standby
+					 (DT2N/DT2Q) */
+	unsigned char dt2p;        /* 51 DRAM Case Temperature Rise from Ambient
+					 due to Precharge Power-Down (DT2P) */
+	unsigned char dt3n;        /* 52 DRAM Case Temperature Rise from Ambient
+					 due to Active Standby (DT3N) */
+	unsigned char dt3pfast;    /* 53 DRAM Case Temperature Rise from Ambient
+					 due to Active Power-Down with
+					 Fast PDN Exit (DT3Pfast) */
+	unsigned char dt3pslow;    /* 54 DRAM Case Temperature Rise from Ambient
+					 due to Active Power-Down with Slow
+					 PDN Exit (DT3Pslow) */
+	unsigned char dt4r_dt4r4w; /* 55 DRAM Case Temperature Rise from Ambient
+					 due to Page Open Burst Read/DT4R4W
+					 Mode Bit (DT4R/DT4R4W Mode Bit) */
+	unsigned char dt5b;        /* 56 DRAM Case Temperature Rise from Ambient
+					 due to Burst Refresh (DT5B) */
+	unsigned char dt7;         /* 57 DRAM Case Temperature Rise from Ambient
+					 due to Bank Interleave Reads with
+					 Auto-Precharge (DT7) */
+	unsigned char psi_ta_pll;  /* 58 Thermal Resistance of PLL Package form
+					 Top (Case) to Ambient (Psi T-A PLL) */
+	unsigned char psi_ta_reg;    /* 59 Thermal Reisitance of Register Package
+					 from Top (Case) to Ambient
+					 (Psi T-A Register) */
+	unsigned char dtpllactive; /* 60 PLL Case Temperature Rise from Ambient
+					 due to PLL Active (DT PLL Active) */
+	unsigned char dtregact;    /* 61 Register Case Temperature Rise from
+					 Ambient due to Register Active/Mode Bit
+					 (DT Register Active/Mode Bit) */
+	unsigned char spd_rev;     /* 62 SPD Data Revision Code */
+	unsigned char cksum;       /* 63 Checksum for bytes 0-62 */
+	unsigned char mid[8];      /* 64 Mfr's JEDEC ID code per JEP-106 */
+	unsigned char mloc;        /* 72 Manufacturing Location */
+	unsigned char mpart[18];   /* 73 Manufacturer's Part Number */
+	unsigned char rev[2];      /* 91 Revision Code */
+	unsigned char mdate[2];    /* 93 Manufacturing Date */
+	unsigned char sernum[4];   /* 95 Assembly Serial Number */
+	unsigned char mspec[27];   /* 99-127 Manufacturer Specific Data */
+
 };
 
-struct ddr3_spd_eeprom_s {
+struct ddr3_spd_eeprom {
 	/* General Section: Bytes 0-59 */
-	uint8_t info_size_crc;   /*  0 # bytes written into serial memory,
+	unsigned char info_size_crc;   /*  0 # bytes written into serial memory,
 					     CRC coverage */
-	uint8_t spd_rev;         /*  1 Total # bytes of SPD mem device */
-	uint8_t mem_type;        /*  2 Key Byte / Fundamental mem type */
-	uint8_t module_type;     /*  3 Key Byte / Module Type */
-	uint8_t density_banks;   /*  4 SDRAM Density and Banks */
-	uint8_t addressing;      /*  5 SDRAM Addressing */
-	uint8_t module_vdd;      /*  6 Module nominal voltage, VDD */
-	uint8_t organization;    /*  7 Module Organization */
-	uint8_t bus_width;       /*  8 Module Memory Bus Width */
-	uint8_t ftb_div;         /*  9 Fine Timebase (FTB)
+	unsigned char spd_rev;         /*  1 Total # bytes of SPD mem device */
+	unsigned char mem_type;        /*  2 Key Byte / Fundamental mem type */
+	unsigned char module_type;     /*  3 Key Byte / Module Type */
+	unsigned char density_banks;   /*  4 SDRAM Density and Banks */
+	unsigned char addressing;      /*  5 SDRAM Addressing */
+	unsigned char module_vdd;      /*  6 Module nominal voltage, VDD */
+	unsigned char organization;    /*  7 Module Organization */
+	unsigned char bus_width;       /*  8 Module Memory Bus Width */
+	unsigned char ftb_div;         /*  9 Fine Timebase (FTB)
 					     Dividend / Divisor */
-	uint8_t mtb_dividend;    /* 10 Medium Timebase (MTB) Dividend */
-	uint8_t mtb_divisor;     /* 11 Medium Timebase (MTB) Divisor */
-	uint8_t tck_min;         /* 12 SDRAM Minimum Cycle Time */
-	uint8_t res_13;          /* 13 Reserved */
-	uint8_t caslat_lsb;      /* 14 CAS Latencies Supported,
+	unsigned char mtb_dividend;    /* 10 Medium Timebase (MTB) Dividend */
+	unsigned char mtb_divisor;     /* 11 Medium Timebase (MTB) Divisor */
+	unsigned char tck_min;         /* 12 SDRAM Minimum Cycle Time */
+	unsigned char res_13;          /* 13 Reserved */
+	unsigned char caslat_lsb;      /* 14 CAS Latencies Supported,
 					     Least Significant Byte */
-	uint8_t caslat_msb;      /* 15 CAS Latencies Supported,
+	unsigned char caslat_msb;      /* 15 CAS Latencies Supported,
 					     Most Significant Byte */
-	uint8_t taa_min;         /* 16 Min CAS Latency Time */
-	uint8_t twr_min;         /* 17 Min Write REcovery Time */
-	uint8_t trcd_min;        /* 18 Min RAS# to CAS# Delay Time */
-	uint8_t trrd_min;        /* 19 Min Row Active to
+	unsigned char taa_min;         /* 16 Min CAS Latency Time */
+	unsigned char twr_min;         /* 17 Min Write REcovery Time */
+	unsigned char trcd_min;        /* 18 Min RAS# to CAS# Delay Time */
+	unsigned char trrd_min;        /* 19 Min Row Active to
 					     Row Active Delay Time */
-	uint8_t trp_min;         /* 20 Min Row Precharge Delay Time */
-	uint8_t tras_trc_ext;    /* 21 Upper Nibbles for tRAS and tRC */
-	uint8_t tras_min_lsb;    /* 22 Min Active to Precharge
+	unsigned char trp_min;         /* 20 Min Row Precharge Delay Time */
+	unsigned char tras_trc_ext;    /* 21 Upper Nibbles for tRAS and tRC */
+	unsigned char tras_min_lsb;    /* 22 Min Active to Precharge
 					     Delay Time */
-	uint8_t trc_min_lsb;     /* 23 Min Active to Active/Refresh
+	unsigned char trc_min_lsb;     /* 23 Min Active to Active/Refresh
 					     Delay Time, LSB */
-	uint8_t trfc_min_lsb;    /* 24 Min Refresh Recovery Delay Time */
-	uint8_t trfc_min_msb;    /* 25 Min Refresh Recovery Delay Time */
-	uint8_t twtr_min;        /* 26 Min Internal Write to
+	unsigned char trfc_min_lsb;    /* 24 Min Refresh Recovery Delay Time */
+	unsigned char trfc_min_msb;    /* 25 Min Refresh Recovery Delay Time */
+	unsigned char twtr_min;        /* 26 Min Internal Write to
 					     Read Command Delay Time */
-	uint8_t trtp_min;        /* 27 Min Internal Read to Precharge
+	unsigned char trtp_min;        /* 27 Min Internal Read to Precharge
 					     Command Delay Time */
-	uint8_t tfaw_msb;        /* 28 Upper Nibble for tFAW */
-	uint8_t tfaw_min;        /* 29 Min Four Activate Window
+	unsigned char tfaw_msb;        /* 28 Upper Nibble for tFAW */
+	unsigned char tfaw_min;        /* 29 Min Four Activate Window
 					     Delay Time*/
-	uint8_t opt_features;    /* 30 SDRAM Optional Features */
-	uint8_t therm_ref_opt;   /* 31 SDRAM Thermal and Refresh Opts */
-	uint8_t therm_sensor;    /* 32 Module Thermal Sensor */
-	uint8_t device_type;     /* 33 SDRAM device type */
-	int8_t fine_tck_min;     /* 34 Fine offset for tCKmin */
-	int8_t fine_taa_min;     /* 35 Fine offset for tAAmin */
-	int8_t fine_trcd_min;    /* 36 Fine offset for tRCDmin */
-	int8_t fine_trp_min;     /* 37 Fine offset for tRPmin */
-	int8_t fine_trc_min;     /* 38 Fine offset for tRCmin */
-	uint8_t res_39_59[21];   /* 39-59 Reserved, General Section */
+	unsigned char opt_features;    /* 30 SDRAM Optional Features */
+	unsigned char therm_ref_opt;   /* 31 SDRAM Thermal and Refresh Opts */
+	unsigned char therm_sensor;    /* 32 Module Thermal Sensor */
+	unsigned char device_type;     /* 33 SDRAM device type */
+	int8_t fine_tck_min;	       /* 34 Fine offset for tCKmin */
+	int8_t fine_taa_min;	       /* 35 Fine offset for tAAmin */
+	int8_t fine_trcd_min;	       /* 36 Fine offset for tRCDmin */
+	int8_t fine_trp_min;	       /* 37 Fine offset for tRPmin */
+	int8_t fine_trc_min;	       /* 38 Fine offset for tRCmin */
+	unsigned char res_39_59[21];   /* 39-59 Reserved, General Section */
 
 	/* Module-Specific Section: Bytes 60-116 */
 	union {
 		struct {
 			/* 60 (Unbuffered) Module Nominal Height */
-			uint8_t mod_height;
+			unsigned char mod_height;
 			/* 61 (Unbuffered) Module Maximum Thickness */
-			uint8_t mod_thickness;
+			unsigned char mod_thickness;
 			/* 62 (Unbuffered) Reference Raw Card Used */
-			uint8_t ref_raw_card;
+			unsigned char ref_raw_card;
 			/* 63 (Unbuffered) Address Mapping from
 			      Edge Connector to DRAM */
-			uint8_t addr_mapping;
+			unsigned char addr_mapping;
 			/* 64-116 (Unbuffered) Reserved */
-			uint8_t res_64_116[53];
+			unsigned char res_64_116[53];
 		} unbuffered;
 		struct {
 			/* 60 (Registered) Module Nominal Height */
-			uint8_t mod_height;
+			unsigned char mod_height;
 			/* 61 (Registered) Module Maximum Thickness */
-			uint8_t mod_thickness;
+			unsigned char mod_thickness;
 			/* 62 (Registered) Reference Raw Card Used */
-			uint8_t ref_raw_card;
+			unsigned char ref_raw_card;
 			/* 63 DIMM Module Attributes */
-			uint8_t modu_attr;
+			unsigned char modu_attr;
 			/* 64 RDIMM Thermal Heat Spreader Solution */
-			uint8_t thermal;
-			/* 65 Register Manufacturer ID Code, LSB */
-			uint8_t reg_id_lo;
-			/* 66 Register Manufacturer ID Code, MSB */
-			uint8_t reg_id_hi;
+			unsigned char thermal;
+			/* 65 Register Manufacturer ID Code, Least Significant Byte */
+			unsigned char reg_id_lo;
+			/* 66 Register Manufacturer ID Code, Most Significant Byte */
+			unsigned char reg_id_hi;
 			/* 67 Register Revision Number */
-			uint8_t reg_rev;
+			unsigned char reg_rev;
 			/* 68 Register Type */
-			uint8_t reg_type;
-			/* 69-76 RC1,3,5..15 (MS Nib.)/RC0,2,4..14 (LS Nib.) */
-			uint8_t rcw[8];
+			unsigned char reg_type;
+			/* 69-76 RC1,3,5...15 (MS Nibble) / RC0,2,4...14 (LS Nibble) */
+			unsigned char rcw[8];
 		} registered;
-		uint8_t uc[57]; /* 60-116 Module-Specific Section */
+		unsigned char uc[57]; /* 60-116 Module-Specific Section */
 	} mod_section;
 
 	/* Unique Module ID: Bytes 117-125 */
-	uint8_t mmid_lsb;        /* 117 Module MfgID Code LSB - JEP-106 */
-	uint8_t mmid_msb;        /* 118 Module MfgID Code MSB - JEP-106 */
-	uint8_t mloc;            /* 119 Mfg Location */
-	uint8_t mdate[2];        /* 120-121 Mfg Date */
-	uint8_t sernum[4];       /* 122-125 Module Serial Number */
+	unsigned char mmid_lsb;        /* 117 Module MfgID Code LSB - JEP-106 */
+	unsigned char mmid_msb;        /* 118 Module MfgID Code MSB - JEP-106 */
+	unsigned char mloc;            /* 119 Mfg Location */
+	unsigned char mdate[2];        /* 120-121 Mfg Date */
+	unsigned char sernum[4];       /* 122-125 Module Serial Number */
 
 	/* CRC: Bytes 126-127 */
-	uint8_t crc[2];          /* 126-127 SPD CRC */
+	unsigned char crc[2];          /* 126-127 SPD CRC */
 
 	/* Other Manufacturer Fields and User Space: Bytes 128-255 */
-	uint8_t mpart[18];       /* 128-145 Mfg's Module Part Number */
-	uint8_t mrev[2];         /* 146-147 Module Revision Code */
-	uint8_t dmid_lsb;        /* 148 DRAM MfgID Code LSB - JEP-106 */
-	uint8_t dmid_msb;        /* 149 DRAM MfgID Code MSB - JEP-106 */
-	uint8_t msd[26];         /* 150-175 Mfg's Specific Data */
-	uint8_t cust[80];        /* 176-255 Open for Customer Use */
+	unsigned char mpart[18];       /* 128-145 Mfg's Module Part Number */
+	unsigned char mrev[2];         /* 146-147 Module Revision Code */
+
+	unsigned char dmid_lsb;        /* 148 DRAM MfgID Code LSB - JEP-106 */
+	unsigned char dmid_msb;        /* 149 DRAM MfgID Code MSB - JEP-106 */
+
+	unsigned char msd[26];         /* 150-175 Mfg's Specific Data */
+	unsigned char cust[80];        /* 176-255 Open for Customer Use */
+
 };
 
-extern void ddr_spd_print(uint8_t *record);
-extern uint32_t ddr3_spd_checksum_pass(const struct ddr3_spd_eeprom_s *spd);
-extern uint32_t ddr2_spd_checksum_pass(const struct ddr2_spd_eeprom_s *spd);
+/* From JEEC Standard No. 21-C release 23A */
+struct ddr4_spd_eeprom {
+	/* General Section: Bytes 0-127 */
+	uint8_t info_size_crc;		/*  0 # bytes */
+	uint8_t spd_rev;		/*  1 Total # bytes of SPD */
+	uint8_t mem_type;		/*  2 Key Byte / mem type */
+	uint8_t module_type;		/*  3 Key Byte / Module Type */
+	uint8_t density_banks;		/*  4 Density and Banks	*/
+	uint8_t addressing;		/*  5 Addressing */
+	uint8_t package_type;		/*  6 Package type */
+	uint8_t opt_feature;		/*  7 Optional features */
+	uint8_t thermal_ref;		/*  8 Thermal and refresh */
+	uint8_t oth_opt_features;	/*  9 Other optional features */
+	uint8_t res_10;			/* 10 Reserved */
+	uint8_t module_vdd;		/* 11 Module nominal voltage */
+	uint8_t organization;		/* 12 Module Organization */
+	uint8_t bus_width;		/* 13 Module Memory Bus Width */
+	uint8_t therm_sensor;		/* 14 Module Thermal Sensor */
+	uint8_t ext_type;		/* 15 Extended module type */
+	uint8_t res_16;
+	uint8_t timebases;		/* 17 MTb and FTB */
+	uint8_t tck_min;		/* 18 tCKAVGmin */
+	uint8_t tck_max;		/* 19 TCKAVGmax */
+	uint8_t caslat_b1;		/* 20 CAS latencies, 1st byte */
+	uint8_t caslat_b2;		/* 21 CAS latencies, 2nd byte */
+	uint8_t caslat_b3;		/* 22 CAS latencies, 3rd byte */
+	uint8_t caslat_b4;		/* 23 CAS latencies, 4th byte */
+	uint8_t taa_min;		/* 24 Min CAS Latency Time */
+	uint8_t trcd_min;		/* 25 Min RAS# to CAS# Delay Time */
+	uint8_t trp_min;		/* 26 Min Row Precharge Delay Time */
+	uint8_t tras_trc_ext;		/* 27 Upper Nibbles for tRAS and tRC */
+	uint8_t tras_min_lsb;		/* 28 tRASmin, lsb */
+	uint8_t trc_min_lsb;		/* 29 tRCmin, lsb */
+	uint8_t trfc1_min_lsb;		/* 30 Min Refresh Recovery Delay Time */
+	uint8_t trfc1_min_msb;		/* 31 Min Refresh Recovery Delay Time */
+	uint8_t trfc2_min_lsb;		/* 32 Min Refresh Recovery Delay Time */
+	uint8_t trfc2_min_msb;		/* 33 Min Refresh Recovery Delay Time */
+	uint8_t trfc4_min_lsb;		/* 34 Min Refresh Recovery Delay Time */
+	uint8_t trfc4_min_msb;		/* 35 Min Refresh Recovery Delay Time */
+	uint8_t tfaw_msb;		/* 36 Upper Nibble for tFAW */
+	uint8_t tfaw_min;		/* 37 tFAW, lsb */
+	uint8_t trrds_min;		/* 38 tRRD_Smin, MTB */
+	uint8_t trrdl_min;		/* 39 tRRD_Lmin, MTB */
+	uint8_t tccdl_min;		/* 40 tCCS_Lmin, MTB */
+	uint8_t res_41[60-41];		/* 41 Rserved */
+	uint8_t mapping[78-60];		/* 60~77 Connector to SDRAM bit map */
+	uint8_t res_78[117-78];		/* 78~116, Reserved */
+	int8_t fine_tccdl_min;		/* 117 Fine offset for tCCD_Lmin */
+	int8_t fine_trrdl_min;		/* 118 Fine offset for tRRD_Lmin */
+	int8_t fine_trrds_min;		/* 119 Fine offset for tRRD_Smin */
+	int8_t fine_trc_min;		/* 120 Fine offset for tRCmin */
+	int8_t fine_trp_min;		/* 121 Fine offset for tRPmin */
+	int8_t fine_trcd_min;		/* 122 Fine offset for tRCDmin */
+	int8_t fine_taa_min;		/* 123 Fine offset for tAAmin */
+	int8_t fine_tck_max;		/* 124 Fine offset for tCKAVGmax */
+	int8_t fine_tck_min;		/* 125 Fine offset for tCKAVGmin */
+	/* CRC: Bytes 126-127 */
+	uint8_t crc[2];			/* 126-127 SPD CRC */
+
+	/* Module-Specific Section: Bytes 128-255 */
+	union {
+		struct {
+			/* 128 (Unbuffered) Module Nominal Height */
+			uint8_t mod_height;
+			/* 129 (Unbuffered) Module Maximum Thickness */
+			uint8_t mod_thickness;
+			/* 130 (Unbuffered) Reference Raw Card Used */
+			uint8_t ref_raw_card;
+			/* 131 (Unbuffered) Address Mapping from
+			      Edge Connector to DRAM */
+			uint8_t addr_mapping;
+			/* 132~253 (Unbuffered) Reserved */
+			uint8_t res_132[254-132];
+			/* 254~255 CRC */
+			uint8_t crc[2];
+		} unbuffered;
+		struct {
+			/* 128 (Registered) Module Nominal Height */
+			uint8_t mod_height;
+			/* 129 (Registered) Module Maximum Thickness */
+			uint8_t mod_thickness;
+			/* 130 (Registered) Reference Raw Card Used */
+			uint8_t ref_raw_card;
+			/* 131 DIMM Module Attributes */
+			uint8_t modu_attr;
+			/* 132 RDIMM Thermal Heat Spreader Solution */
+			uint8_t thermal;
+			/* 133 Register Manufacturer ID Code, LSB */
+			uint8_t reg_id_lo;
+			/* 134 Register Manufacturer ID Code, MSB */
+			uint8_t reg_id_hi;
+			/* 135 Register Revision Number */
+			uint8_t reg_rev;
+			/* 136 Address mapping from register to DRAM */
+			u8 reg_map;
+			u8 ca_stren;
+			u8 clk_stren;
+			/* 139~253 Reserved */
+			u8 res_137[254 - 139];
+			/* 254~255 CRC */
+			uint8_t crc[2];
+		} registered;
+		struct {
+			/* 128 (Loadreduced) Module Nominal Height */
+			uint8_t mod_height;
+			/* 129 (Loadreduced) Module Maximum Thickness */
+			uint8_t mod_thickness;
+			/* 130 (Loadreduced) Reference Raw Card Used */
+			uint8_t ref_raw_card;
+			/* 131 DIMM Module Attributes */
+			uint8_t modu_attr;
+			/* 132 RDIMM Thermal Heat Spreader Solution */
+			uint8_t thermal;
+			/* 133 Register Manufacturer ID Code, LSB */
+			uint8_t reg_id_lo;
+			/* 134 Register Manufacturer ID Code, MSB */
+			uint8_t reg_id_hi;
+			/* 135 Register Revision Number */
+			uint8_t reg_rev;
+			/* 136 Address mapping from register to DRAM */
+			uint8_t reg_map;
+			/* 137 Register Output Drive Strength for CMD/Add*/
+			uint8_t reg_drv;
+			/* 138 Register Output Drive Strength for CK */
+			uint8_t reg_drv_ck;
+			/* 139 Data Buffer Revision Number */
+			uint8_t data_buf_rev;
+			/* 140 DRAM VrefDQ for Package Rank 0 */
+			uint8_t vrefqe_r0;
+			/* 141 DRAM VrefDQ for Package Rank 1 */
+			uint8_t vrefqe_r1;
+			/* 142 DRAM VrefDQ for Package Rank 2 */
+			uint8_t vrefqe_r2;
+			/* 143 DRAM VrefDQ for Package Rank 3 */
+			uint8_t vrefqe_r3;
+			/* 144 Data Buffer VrefDQ for DRAM Interface */
+			uint8_t data_intf;
+			/*
+			 * 145 Data Buffer MDQ Drive Strength and RTT
+			 * for data rate <= 1866
+			 */
+			uint8_t data_drv_1866;
+			/*
+			 * 146 Data Buffer MDQ Drive Strength and RTT
+			 * for 1866 < data rate <= 2400
+			 */
+			uint8_t data_drv_2400;
+			/*
+			 * 147 Data Buffer MDQ Drive Strength and RTT
+			 * for 2400 < data rate <= 3200
+			 */
+			uint8_t data_drv_3200;
+			/* 148 DRAM Drive Strength */
+			uint8_t dram_drv;
+			/*
+			 * 149 DRAM ODT (RTT_WR, RTT_NOM)
+			 * for data rate <= 1866
+			 */
+			uint8_t dram_odt_1866;
+			/*
+			 * 150 DRAM ODT (RTT_WR, RTT_NOM)
+			 * for 1866 < data rate <= 2400
+			 */
+			uint8_t dram_odt_2400;
+			/*
+			 * 151 DRAM ODT (RTT_WR, RTT_NOM)
+			 * for 2400 < data rate <= 3200
+			 */
+			uint8_t dram_odt_3200;
+			/*
+			 * 152 DRAM ODT (RTT_PARK)
+			 * for data rate <= 1866
+			 */
+			uint8_t dram_odt_park_1866;
+			/*
+			 * 153 DRAM ODT (RTT_PARK)
+			 * for 1866 < data rate <= 2400
+			 */
+			uint8_t dram_odt_park_2400;
+			/*
+			 * 154 DRAM ODT (RTT_PARK)
+			 * for 2400 < data rate <= 3200
+			 */
+			uint8_t dram_odt_park_3200;
+			uint8_t res_155[254-155];	/* Reserved */
+			/* 254~255 CRC */
+			uint8_t crc[2];
+		} loadreduced;
+		uint8_t uc[128]; /* 128-255 Module-Specific Section */
+	} mod_section;
+
+	uint8_t res_256[320-256];	/* 256~319 Reserved */
+
+	/* Module supplier's data: Byte 320~383 */
+	uint8_t mmid_lsb;		/* 320 Module MfgID Code LSB */
+	uint8_t mmid_msb;		/* 321 Module MfgID Code MSB */
+	uint8_t mloc;			/* 322 Mfg Location */
+	uint8_t mdate[2];		/* 323~324 Mfg Date */
+	uint8_t sernum[4];		/* 325~328 Module Serial Number */
+	uint8_t mpart[20];		/* 329~348 Mfg's Module Part Number */
+	uint8_t mrev;			/* 349 Module Revision Code */
+	uint8_t dmid_lsb;		/* 350 DRAM MfgID Code LSB */
+	uint8_t dmid_msb;		/* 351 DRAM MfgID Code MSB */
+	uint8_t stepping;		/* 352 DRAM stepping */
+	uint8_t msd[29];		/* 353~381 Mfg's Specific Data */
+	uint8_t res_382[2];		/* 382~383 Reserved */
 
-/* * Byte 2 Fundamental Memory Types. */
+	uint8_t user[512-384];		/* 384~511 End User Programmable */
+};
+
+/*
+ * Byte 2 Fundamental Memory Types.
+ */
+#define SPD_MEMTYPE_FPM		(0x01)
+#define SPD_MEMTYPE_EDO		(0x02)
+#define SPD_MEMTYPE_PIPE_NIBBLE	(0x03)
+#define SPD_MEMTYPE_SDRAM	(0x04)
+#define SPD_MEMTYPE_ROM		(0x05)
+#define SPD_MEMTYPE_SGRAM	(0x06)
+#define SPD_MEMTYPE_DDR		(0x07)
 #define SPD_MEMTYPE_DDR2	(0x08)
+#define SPD_MEMTYPE_DDR2_FBDIMM	(0x09)
+#define SPD_MEMTYPE_DDR2_FBDIMM_PROBE	(0x0A)
 #define SPD_MEMTYPE_DDR3	(0x0B)
+#define SPD_MEMTYPE_DDR4	(0x0C)
 
 /* DIMM Type for DDR2 SPD (according to v1.3) */
+#define DDR2_SPD_DIMMTYPE_UNDEFINED	(0x00)
 #define DDR2_SPD_DIMMTYPE_RDIMM		(0x01)
 #define DDR2_SPD_DIMMTYPE_UDIMM		(0x02)
 #define DDR2_SPD_DIMMTYPE_SO_DIMM	(0x04)
@@ -247,6 +525,41 @@ extern uint32_t ddr2_spd_checksum_pass(const struct ddr2_spd_eeprom_s *spd);
 #define DDR2_SPD_DIMMTYPE_MINI_UDIMM	(0x20)
 
 /* Byte 3 Key Byte / Module Type for DDR3 SPD */
-#define DDR3_SPD_MODULETYPE_MASK	(0x0F)
+#define DDR3_SPD_MODULETYPE_MASK	(0x0f)
+#define DDR3_SPD_MODULETYPE_RDIMM	(0x01)
 #define DDR3_SPD_MODULETYPE_UDIMM	(0x02)
+#define DDR3_SPD_MODULETYPE_SO_DIMM	(0x03)
+#define DDR3_SPD_MODULETYPE_MICRO_DIMM	(0x04)
+#define DDR3_SPD_MODULETYPE_MINI_RDIMM	(0x05)
+#define DDR3_SPD_MODULETYPE_MINI_UDIMM	(0x06)
+#define DDR3_SPD_MODULETYPE_MINI_CDIMM	(0x07)
+#define DDR3_SPD_MODULETYPE_72B_SO_UDIMM	(0x08)
+#define DDR3_SPD_MODULETYPE_72B_SO_RDIMM	(0x09)
+#define DDR3_SPD_MODULETYPE_72B_SO_CDIMM	(0x0A)
+#define DDR3_SPD_MODULETYPE_LRDIMM	(0x0B)
+#define DDR3_SPD_MODULETYPE_16B_SO_DIMM	(0x0C)
+#define DDR3_SPD_MODULETYPE_32B_SO_DIMM	(0x0D)
+
+/* DIMM Type for DDR4 SPD */
+#define DDR4_SPD_MODULETYPE_MASK	(0x0f)
+#define DDR4_SPD_MODULETYPE_EXT		(0x00)
+#define DDR4_SPD_MODULETYPE_RDIMM	(0x01)
+#define DDR4_SPD_MODULETYPE_UDIMM	(0x02)
+#define DDR4_SPD_MODULETYPE_SO_DIMM	(0x03)
+#define DDR4_SPD_MODULETYPE_LRDIMM	(0x04)
+#define DDR4_SPD_MODULETYPE_MINI_RDIMM	(0x05)
+#define DDR4_SPD_MODULETYPE_MINI_UDIMM	(0x06)
+#define DDR4_SPD_MODULETYPE_72B_SO_UDIMM	(0x08)
+#define DDR4_SPD_MODULETYPE_72B_SO_RDIMM	(0x09)
+#define DDR4_SPD_MODULETYPE_16B_SO_DIMM	(0x0C)
+#define DDR4_SPD_MODULETYPE_32B_SO_DIMM	(0x0D)
+
+void ddr_spd_print(uint8_t *record);
+int ddr1_spd_check(const struct ddr1_spd_eeprom *spd);
+void ddr1_spd_dump(const struct ddr1_spd_eeprom *spd);
+int ddr2_spd_check(const struct ddr2_spd_eeprom *spd);
+void ddr2_spd_dump(const struct ddr2_spd_eeprom *spd);
+int ddr3_spd_check(const struct ddr3_spd_eeprom *spd);
+int ddr4_spd_check(const struct ddr4_spd_eeprom *spd);
+
 #endif /* _DDR_SPD_H_ */
-- 
2.20.1


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[PATCH 4/6] ddr_spd: Add function to read eeprom

[Sascha Hauer]

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 common/ddr_spd.c  | 81 +++++++++++++++++++++++++++++++++++++++++++++++
 include/ddr_spd.h |  6 ++++
 2 files changed, 87 insertions(+)

diff --git a/common/ddr_spd.c b/common/ddr_spd.c
index 9394c57fa3..a878790550 100644
--- a/common/ddr_spd.c
+++ b/common/ddr_spd.c
@@ -429,3 +429,84 @@ void ddr_spd_print(uint8_t *record)
 		printf("%02X", record[i]);
 	printf("\n");
 }
+
+#define SPD_SPA0_ADDRESS        0x36
+#define SPD_SPA1_ADDRESS        0x37
+
+static int select_page(void *ctx,
+	      int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
+	      uint8_t addr)
+{
+	struct i2c_msg msg = {
+		.addr = addr,
+		.len = 0,
+	};
+	int ret;
+
+	ret = xfer(ctx, &msg, 1);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int read_buf(void *ctx,
+	      int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
+	      uint8_t addr, int page, void *buf)
+{
+	uint8_t pos = 0;
+	int ret;
+	struct i2c_msg msg[2] = {
+		{
+			.addr = addr,
+			.len = 1,
+			.buf = &pos,
+		}, {
+			.addr = addr,
+			.len = 256,
+			.flags = I2C_M_RD,
+			.buf = buf,
+		}
+	};
+
+	ret = select_page(ctx, xfer, page);
+	if (ret < 0)
+		return ret;
+
+	ret = xfer(ctx, msg, 2);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+/**
+ * spd_read_eeprom - Read contents of a SPD EEPROM
+ * @ctx: Context pointer for the xfer function
+ * @xfer: I2C message transfer function
+ * @addr: I2C bus address for the EEPROM
+ * @buf: buffer to read the SPD data to
+ *
+ * This function takes a I2C message transfer function and reads the contents
+ * from a SPD EEPROM to the buffer provided at @buf. Returns 0 for success or a
+ * negative error code otherwise.
+ */
+int spd_read_eeprom(void *ctx,
+		    int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
+		    uint8_t addr, void *buf)
+{
+	unsigned char *buf8 = buf;
+	int ret;
+
+	ret = read_buf(ctx, xfer, addr, SPD_SPA0_ADDRESS, buf);
+	if (ret < 0)
+		return ret;
+
+	if (buf8[2] == SPD_MEMTYPE_DDR4) {
+		ret = read_buf(ctx, xfer, addr, SPD_SPA1_ADDRESS, buf + 256);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
diff --git a/include/ddr_spd.h b/include/ddr_spd.h
index 051275141f..95d0eb04b6 100644
--- a/include/ddr_spd.h
+++ b/include/ddr_spd.h
@@ -6,6 +6,8 @@
 #ifndef _DDR_SPD_H_
 #define _DDR_SPD_H_
 
+#include <i2c/i2c.h>
+
 /*
  * Format from "JEDEC Standard No. 21-C,
  * Appendix D: Rev 1.0: SPD's for DDR SDRAM
@@ -562,4 +564,8 @@ void ddr2_spd_dump(const struct ddr2_spd_eeprom *spd);
 int ddr3_spd_check(const struct ddr3_spd_eeprom *spd);
 int ddr4_spd_check(const struct ddr4_spd_eeprom *spd);
 
+int spd_read_eeprom(void *ctx,
+		    int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
+		    uint8_t addr, void *buf);
+
 #endif /* _DDR_SPD_H_ */
-- 
2.20.1


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[PATCH 5/6] ddr_spd: provide common SPD type

[Sascha Hauer]

Provide a common struct type for the different SPD EEPROM types. Can be
used to pass around SPD data without specifying the DDR type.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 include/ddr_spd.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/include/ddr_spd.h b/include/ddr_spd.h
index 95d0eb04b6..6e63d90e5e 100644
--- a/include/ddr_spd.h
+++ b/include/ddr_spd.h
@@ -499,6 +499,16 @@ struct ddr4_spd_eeprom {
 	uint8_t user[512-384];		/* 384~511 End User Programmable */
 };
 
+struct spd_eeprom {
+	union {
+		struct ddr1_spd_eeprom ddr1;
+		struct ddr2_spd_eeprom ddr2;
+		struct ddr3_spd_eeprom ddr3;
+		struct ddr4_spd_eeprom ddr4;
+		uint8_t data[512];
+	};
+};
+
 /*
  * Byte 2 Fundamental Memory Types.
  */
-- 
2.20.1


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[PATCH 6/6] ddr_spd: Enable in PBL

[Sascha Hauer]

SPD EEPROMs are typically needed in PBL when the SDRAM is not yet
initialized. Enable compilation of the SPD support in PBL.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 common/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/common/Makefile b/common/Makefile
index b617642242..a284655fc1 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -24,7 +24,7 @@ obj-$(CONFIG_COMMAND_SUPPORT)	+= command.o
 obj-$(CONFIG_CONSOLE_FULL)	+= console.o
 obj-$(CONFIG_CONSOLE_SIMPLE)	+= console_simple.o
 obj-y				+= console_countdown.o
-obj-$(CONFIG_DDR_SPD)		+= ddr_spd.o
+obj-pbl-$(CONFIG_DDR_SPD)	+= ddr_spd.o
 obj-$(CONFIG_ENV_HANDLING)	+= environment.o
 obj-$(CONFIG_ENVIRONMENT_VARIABLES) += env.o
 obj-$(CONFIG_FILETYPE)		+= filetype.o
-- 
2.20.1


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Re: [PATCH 1/6] crc: import crc_itu_t() from kernel

[Sam Ravnborg]

On Mon, Mar 04, 2019 at 12:38:18PM +0100, Sascha Hauer wrote:
> Out cyc_crc16() function is the same function as crc_itu_t() in the
s/Out/barebox/
> Linux kernel. Import and use crc_itu_t() from the Kernel for
> consistency.
> 
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

	Sam

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Re: [PATCH 4/6] ddr_spd: Add function to read eeprom

[Sam Ravnborg]

On Mon, Mar 04, 2019 at 12:38:21PM +0100, Sascha Hauer wrote:
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> ---
>  common/ddr_spd.c  | 81 +++++++++++++++++++++++++++++++++++++++++++++++
>  include/ddr_spd.h |  6 ++++
>  2 files changed, 87 insertions(+)
> 
> diff --git a/common/ddr_spd.c b/common/ddr_spd.c
> index 9394c57fa3..a878790550 100644
> --- a/common/ddr_spd.c
> +++ b/common/ddr_spd.c
> @@ -429,3 +429,84 @@ void ddr_spd_print(uint8_t *record)
>  		printf("%02X", record[i]);
>  	printf("\n");
>  }
> +
> +#define SPD_SPA0_ADDRESS        0x36
> +#define SPD_SPA1_ADDRESS        0x37
> +
> +static int select_page(void *ctx,
> +	      int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
> +	      uint8_t addr)

Indent looks strange.

> +
> +static int read_buf(void *ctx,
> +	      int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
> +	      uint8_t addr, int page, void *buf)
Same here.

> +/**
> + * spd_read_eeprom - Read contents of a SPD EEPROM
> + * @ctx: Context pointer for the xfer function
> + * @xfer: I2C message transfer function
> + * @addr: I2C bus address for the EEPROM
> + * @buf: buffer to read the SPD data to
> + *
> + * This function takes a I2C message transfer function and reads the contents
> + * from a SPD EEPROM to the buffer provided at @buf. Returns 0 for success or a
> + * negative error code otherwise.
> + */
> +int spd_read_eeprom(void *ctx,
> +		    int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
> +		    uint8_t addr, void *buf)
> +{
This looks okay.

I may have missed some trivial logic problems while my focus was at the
very important indentation - sorry :-)

	Sam

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Re: [PATCH 4/6] ddr_spd: Add function to read eeprom

[Sam Ravnborg]

Hi Sascha

On Mon, Mar 04, 2019 at 12:38:21PM +0100, Sascha Hauer wrote:
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> ---
>  common/ddr_spd.c  | 81 +++++++++++++++++++++++++++++++++++++++++++++++
>  include/ddr_spd.h |  6 ++++
>  2 files changed, 87 insertions(+)
> 
> diff --git a/common/ddr_spd.c b/common/ddr_spd.c
> index 9394c57fa3..a878790550 100644
> --- a/common/ddr_spd.c
> +++ b/common/ddr_spd.c
> @@ -429,3 +429,84 @@ void ddr_spd_print(uint8_t *record)
>  		printf("%02X", record[i]);
>  	printf("\n");
>  }
> +
> +#define SPD_SPA0_ADDRESS        0x36
> +#define SPD_SPA1_ADDRESS        0x37
> +
> +static int select_page(void *ctx,
> +	      int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
> +	      uint8_t addr)
> +{
> +	struct i2c_msg msg = {
> +		.addr = addr,
> +		.len = 0,
> +	};
> +	int ret;
> +
> +	ret = xfer(ctx, &msg, 1);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +static int read_buf(void *ctx,
> +	      int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
> +	      uint8_t addr, int page, void *buf)
> +{
> +	uint8_t pos = 0;
> +	int ret;
> +	struct i2c_msg msg[2] = {
> +		{
> +			.addr = addr,
> +			.len = 1,
> +			.buf = &pos,
> +		}, {
> +			.addr = addr,
> +			.len = 256,
> +			.flags = I2C_M_RD,
> +			.buf = buf,
> +		}
> +	};
> +
> +	ret = select_page(ctx, xfer, page);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = xfer(ctx, msg, 2);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +/**
> + * spd_read_eeprom - Read contents of a SPD EEPROM
> + * @ctx: Context pointer for the xfer function
> + * @xfer: I2C message transfer function
> + * @addr: I2C bus address for the EEPROM
> + * @buf: buffer to read the SPD data to
It is not obvious what buffer size to provide here.
And if it happens to be SPD_MEMTYPE_DDR4 then we suddenly start to
write data at offset 256 in the buffer.
So maybe add a small comment that this should always be 512 bytes.
Or even better 2 x SPD_PAGE_SIZE (defined to 256)


> + *
> + * This function takes a I2C message transfer function and reads the contents
> + * from a SPD EEPROM to the buffer provided at @buf. Returns 0 for success or a
> + * negative error code otherwise.
> + */
> +int spd_read_eeprom(void *ctx,
> +		    int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
> +		    uint8_t addr, void *buf)
> +{
> +	unsigned char *buf8 = buf;
> +	int ret;
> +
> +	ret = read_buf(ctx, xfer, addr, SPD_SPA0_ADDRESS, buf);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (buf8[2] == SPD_MEMTYPE_DDR4) {
> +		ret = read_buf(ctx, xfer, addr, SPD_SPA1_ADDRESS, buf + 256);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> diff --git a/include/ddr_spd.h b/include/ddr_spd.h
> index 051275141f..95d0eb04b6 100644
> --- a/include/ddr_spd.h
> +++ b/include/ddr_spd.h
> @@ -6,6 +6,8 @@
>  #ifndef _DDR_SPD_H_
>  #define _DDR_SPD_H_
>  
> +#include <i2c/i2c.h>
> +
>  /*
>   * Format from "JEDEC Standard No. 21-C,
>   * Appendix D: Rev 1.0: SPD's for DDR SDRAM
> @@ -562,4 +564,8 @@ void ddr2_spd_dump(const struct ddr2_spd_eeprom *spd);
>  int ddr3_spd_check(const struct ddr3_spd_eeprom *spd);
>  int ddr4_spd_check(const struct ddr4_spd_eeprom *spd);
>  
> +int spd_read_eeprom(void *ctx,
> +		    int (*xfer)(void *ctx, struct i2c_msg *msgs, int num),
> +		    uint8_t addr, void *buf);
> +
>  #endif /* _DDR_SPD_H_ */
> -- 
> 2.20.1
> 
> 
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Re: [PATCH 1/6] crc: import crc_itu_t() from kernel

[Sascha Hauer]

On Mon, Mar 04, 2019 at 12:50:06PM +0100, Sam Ravnborg wrote:
> On Mon, Mar 04, 2019 at 12:38:18PM +0100, Sascha Hauer wrote:
> > Out cyc_crc16() function is the same function as crc_itu_t() in the
> s/Out/barebox/

Should read "Our". Thanks, fixed.

Sascha


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Re: [PATCH 4/6] ddr_spd: Add function to read eeprom

[Sascha Hauer]

Hi Sam,

On Mon, Mar 04, 2019 at 01:02:52PM +0100, Sam Ravnborg wrote:
> Hi Sascha
> 
> On Mon, Mar 04, 2019 at 12:38:21PM +0100, Sascha Hauer wrote:
> > +/**
> > + * spd_read_eeprom - Read contents of a SPD EEPROM
> > + * @ctx: Context pointer for the xfer function
> > + * @xfer: I2C message transfer function
> > + * @addr: I2C bus address for the EEPROM
> > + * @buf: buffer to read the SPD data to
> It is not obvious what buffer size to provide here.
> And if it happens to be SPD_MEMTYPE_DDR4 then we suddenly start to
> write data at offset 256 in the buffer.
> So maybe add a small comment that this should always be 512 bytes.
> Or even better 2 x SPD_PAGE_SIZE (defined to 256)

Make sense, I added such a comment.

Thanks
Sascha

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
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