Change in flashrom[master]: ichspi.c: Implement ich_hwseq_get_flash_id()

[Edward O'Callaghan (Code Review)]

Edward O'Callaghan has uploaded this change for review. ( https://review.coreboot.org/c/flashrom/+/48133 )

Change subject: ichspi.c: Implement ich_hwseq_get_flash_id()
......................................................................

ichspi.c: Implement ich_hwseq_get_flash_id()

Allow for decoding the SPI flash vid:did and to allow lookup
and copying it from the flashchips database. This allows
Flashrom to provide the user the real SPI flash chip name
instead of 'Opaque flash chip'.

before:
```
 $ sudo ./flashrom -p internal --flash-name 2>&1 | grep 'Found '
Found chipset "Intel Kaby Lake U w/ iHDCP2.2 Prem.".
Found Programmer flash chip "Opaque flash chip" (16384 kB, Programmer-specific) mapped at physical address 0x0000000000000000.
```

after:
```
 $ sudo ./flashrom -p internal --flash-name 2>&1 | grep 'Found '
Found chipset "Intel Kaby Lake U w/ iHDCP2.2 Prem.".
Found Winbond flash chip "W25Q128.V" (16384 kB, Programmer-specific) mapped at physical address 0x0000000000000000.
```

BUG=none
TEST=`flashrom -p internal --flash-name`

Change-Id: Icdf684e21b19ee87b797092f3cf0353e1184291f
Signed-off-by: Edward O'Callaghan 
---
M ichspi.c
1 file changed, 82 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/33/48133/1

diff --git a/ichspi.c b/ichspi.c
index 4209d60..45afe5b 100644
--- a/ichspi.c
+++ b/ichspi.c
@@ -78,8 +78,17 @@
 #define DLOCK_SSEQ_LOCKDN_OFF	16
 #define DLOCK_SSEQ_LOCKDN	(0x1 << DLOCK_SSEQ_LOCKDN_OFF)

+/* Control bits */
+#define HSFSC_FGO_OFF		16	/* 0: Flash Cycle Go */
+#define HSFSC_FGO		(0x1 << HSFSC_FGO_OFF)
+#define HSFSC_FCYCLE_OFF	17	/* 17-20: FLASH Cycle */
+#define HSFSC_FCYCLE		(0xf << HSFSC_FCYCLE_OFF)
+#define HSFSC_FDBC_OFF		24	/* 24-29 : Flash Data Byte Count */
+#define HSFSC_FDBC		(0x3f << HSFSC_FDBC_OFF)
+
 #define PCH100_REG_FPR0		0x84	/* 32 Bits Protected Range 0 */
 #define PCH100_REG_GPR0		0x98	/* 32 Bits Global Protected Range 0 */
+#define PCH100_REG_HSFSC	0x04

#define PCH100_REG_SSFSC	0xA0	/* 32 Bits Status (8) + Control (24) */
 #define PCH100_REG_PREOP	0xA4	/* 16 Bits */
@@ -1321,12 +1330,85 @@
    return 0;
 }

+/* Given RDID info, return pointer to entry in flashchips[] */
+static const struct flashchip *flash_id_to_entry(uint32_t mfg_id, uint32_t model_id)
+{
+	const struct flashchip *chip;
+
+	for (chip = &flashchips[0]; chip->vendor; chip++) {
+		if ((chip->manufacture_id == mfg_id) &&
+			(chip->model_id == model_id))
+			return chip;
+	}
+
+	return NULL;
+}
+
+static int ich_hwseq_get_flash_id(struct flashctx *flash, enum ich_chipset ich_gen)
+{
+	uint32_t hsfsc, data, mfg_id, model_id;
+	const struct flashchip *entry;
+	const int len = sizeof(data);
+
+	/* make sure FDONE, FCERR, & AEL are cleared */
+	REGWRITE32(ICH9_REG_HSFS, REGREAD32(ICH9_REG_HSFS));
+
+	/* Set RDID as flash cycle and FGO */
+	hsfsc = REGREAD32(ICH9_REG_HSFS);
+	hsfsc &= ~HSFSC_FCYCLE;
+	hsfsc &= ~HSFSC_FDBC;
+	hsfsc |= ((len - 1) << HSFSC_FDBC_OFF) & HSFSC_FDBC;
+	hsfsc |= (0x6 << HSFSC_FCYCLE_OFF) | HSFSC_FGO;
+	REGWRITE32(ICH9_REG_HSFS, hsfsc);
+	/* poll for 100ms */
+	if (ich_hwseq_wait_for_cycle_complete(100 * 1000, len, ich_gen)) {
+		msg_perr("Timed out waiting for RDID to complete.\n");
+		return 0;
+	}
+
+	/*
+	 * Data will appear in reverse order:
+	 * Byte 0: Manufacturer ID
+	 * Byte 1: Model ID (MSB)
+	 * Byte 2: Model ID (LSB)
+	 */
+	ich_read_data((uint8_t *)&data, len, ICH9_REG_FDATA0);
+	mfg_id = data & 0xff;
+	model_id = (data & 0xff00) | ((data >> 16) & 0xff);
+
+	entry = flash_id_to_entry(mfg_id, model_id);
+	if (entry == NULL) {
+		msg_perr("Unable to identify chip, mfg_id: 0x%02x, "
+				"model_id: 0x%02x\n", mfg_id, model_id);
+		return 0;
+	} else {
+		msg_pdbg("Chip identified: %s\n", entry->name);
+		/* Update informational flash chip entries only */
+		flash->chip->vendor = entry->vendor;
+		flash->chip->name = entry->name;
+		flash->chip->manufacture_id = entry->manufacture_id;
+		flash->chip->model_id = entry->model_id;
+		/* total_size read from flash descriptor */
+		flash->chip->page_size = entry->page_size;
+		flash->chip->feature_bits = entry->feature_bits;
+		flash->chip->tested = entry->tested;
+		flash->chip->wp = entry->wp;
+	}
+
+	return 1;
+}
+
 static int ich_hwseq_probe(struct flashctx *flash)
 {
    uint32_t total_size, boundary;
    uint32_t erase_size_low, size_low, erase_size_high, size_high;
    struct block_eraser *eraser;

+	if (ich_hwseq_get_flash_id(flash, ich_generation) != 1) {
+		msg_perr("Unable to read flash chip ID\n");
+		return 0;
+	}
+
    total_size = hwseq_data.size_comp0 + hwseq_data.size_comp1;
    msg_cdbg("Hardware sequencing reports %d attached SPI flash chip",
    	 (hwseq_data.size_comp1 != 0) ? 2 : 1);