nrf51: Add a known devices table and simple chip type detection code

Unfortunately due to my oversight, the original version of the
nrf51_probe function contained useless code that read the contents of
DEVICEID[0] an DEVICEID[1] registers and did nothing about it(those
registers had nothing to do with the device type information anyway).

This commit fixes that code by changing its behavior to read the HWID
field of CONFIGID register and looking up the corresponding device
information in the know devices table. This information is useful
when choosing the versions of SDK and SoftDevice for the chip
using "nRF51822 compatibility matrix".

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Change-Id: Ibd80b35460df4278e86e0c2500b7dcc876eec10c
Reviewed-on: http://openocd.zylin.com/2012
Tested-by: jenkins
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>

1 files changed, 109 insertions, 7 deletions

diff --git a/src/flash/nor/nrf51.c b/src/flash/nor/nrf51.c
index 444db611..7820baf5 100644
--- a/src/flash/nor/nrf51.c
+++ b/src/flash/nor/nrf51.c
@@ -109,6 +109,91 @@ struct nrf51_info {
 	struct target *target;
 };
 
+struct nrf51_device_spec {
+	uint16_t hwid;
+	const char *variant;
+	const char *build_code;
+	unsigned int flash_size_kb;
+};
+
+static const struct nrf51_device_spec nrf51_known_devices_table[] = {
+	{
+		.hwid		= 0x001D,
+		.variant	= "QFAA",
+		.build_code	= "CA/C0",
+		.flash_size_kb	= 256,
+	},
+	{
+		.hwid		= 0x002A,
+		.variant	= "QFAA",
+		.build_code	= "FA",
+		.flash_size_kb	= 256,
+	},
+	{
+		.hwid		= 0x0044,
+		.variant	= "QFAA",
+		.build_code	= "GC",
+		.flash_size_kb	= 256,
+	},
+	{
+		.hwid		= 0x003C,
+		.variant	= "QFAA",
+		.build_code	= "G0",
+		.flash_size_kb	= 256,
+	},
+
+	{
+		.hwid		= 0x0020,
+		.variant	= "CEAA",
+		.build_code	= "BA",
+		.flash_size_kb	= 256,
+	},
+	{
+		.hwid		= 0x002F,
+		.variant	= "CEAA",
+		.build_code	= "B0",
+		.flash_size_kb	= 256,
+	},
+	{
+		.hwid		= 0x0040,
+		.variant	= "CEAA",
+		.build_code	= "CA",
+		.flash_size_kb	= 256,
+	},
+	{
+		.hwid		= 0x0047,
+		.variant	= "CEAA",
+		.build_code	= "DA",
+		.flash_size_kb	= 256,
+	},
+	{
+		.hwid		= 0x004D,
+		.variant	= "CEAA",
+		.build_code	= "D0",
+		.flash_size_kb	= 256,
+	},
+
+	{
+		.hwid		= 0x0026,
+		.variant	= "QFAB",
+		.build_code	= "AA",
+		.flash_size_kb	= 128,
+	},
+	{
+		.hwid		= 0x0027,
+		.variant	= "QFAB",
+		.build_code	= "A0",
+		.flash_size_kb	= 128,
+	},
+	{
+		.hwid		= 0x004C,
+		.variant	= "QFAB",
+		.build_code	= "B0",
+		.flash_size_kb	= 128,
+	},
+
+};
+
 static int nrf51_probe(struct flash_bank *bank);
 
 static int nrf51_get_probed_chip_if_halted(struct flash_bank *bank, struct nrf51_info **chip)
@@ -330,20 +415,32 @@ static int nrf51_protect(struct flash_bank *bank, int set, int first, int last)
 
 static int nrf51_probe(struct flash_bank *bank)
 {
-	uint32_t id;
+	uint32_t hwid;
 	int res;
 	struct nrf51_info *chip = (struct nrf51_info *)bank->driver_priv;
 
-	res = target_read_u32(chip->target, NRF51_FICR_DEVICEID0, &id);
+
+	res = target_read_u32(chip->target, NRF51_FICR_CONFIGID, &hwid);
 	if (res != ERROR_OK) {
-		LOG_ERROR("Couldn't read Device ID 0 register");
+		LOG_ERROR("Couldn't read CONFIGID register");
 		return res;
 	}
 
-	res = target_read_u32(chip->target, NRF51_FICR_DEVICEID1, &id);
-	if (res != ERROR_OK) {
-		LOG_ERROR("Couldn't read Device ID 1 register");
-		return res;
+	hwid &= 0xFFFF;	/* HWID is stored in the lower two
+			 * bytes of the CONFIGID register */
+
+	const struct nrf51_device_spec *spec = NULL;
+	for (size_t i = 0; i < ARRAY_SIZE(nrf51_known_devices_table); i++)
+		if (hwid == nrf51_known_devices_table[i].hwid) {
+			spec = &nrf51_known_devices_table[i];
+			break;
+		}
+
+	if (spec) {
+		LOG_INFO("nRF51822-%s(build code: %s) %ukB Flash",
+			 spec->variant, spec->build_code, spec->flash_size_kb);
+	} else {
+		LOG_WARNING("Unknown device (HWID 0x%08" PRIx32 ")", hwid);
 	}
 
 	res = target_read_u32(chip->target, NRF51_FICR_CODEPAGESIZE,
@@ -360,6 +457,11 @@ static int nrf51_probe(struct flash_bank *bank)
 		return res;
 	}
 
+	if (spec && chip->code_memory_size != spec->flash_size_kb) {
+		LOG_ERROR("Chip's reported Flash capacity does not match expected one");
+		return ERROR_FAIL;
+	}
+
 	bank->size = chip->code_memory_size * 1024;
 	bank->num_sectors = bank->size / chip->code_page_size;
 	bank->sectors = calloc(bank->num_sectors,