[SSB]: add Sonics Silicon Backplane bus support

SSB is an SoC bus used in a number of embedded devices.  The most
well-known of these devices is probably the Linksys WRT54G, but there
are others as well.  The bus is also used internally on the BCM43xx
and BCM44xx devices from Broadcom.

This patch also includes support for SSB ID tables in modules, so
that SSB drivers can be loaded automatically.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 740 insertions, 0 deletions

diff --git a/drivers/ssb/pci.c b/drivers/ssb/pci.c
new file mode 100644
index 00000000000..3d23ca4befe
--- /dev/null
+++ b/drivers/ssb/pci.c
@@ -0,0 +1,740 @@
+/*
+ * Sonics Silicon Backplane PCI-Hostbus related functions.
+ *
+ * Copyright (C) 2005-2006 Michael Buesch <mb@bu3sch.de>
+ * Copyright (C) 2005 Martin Langer <martin-langer@gmx.de>
+ * Copyright (C) 2005 Stefano Brivio <st3@riseup.net>
+ * Copyright (C) 2005 Danny van Dyk <kugelfang@gentoo.org>
+ * Copyright (C) 2005 Andreas Jaggi <andreas.jaggi@waterwave.ch>
+ *
+ * Derived from the Broadcom 4400 device driver.
+ * Copyright (C) 2002 David S. Miller (davem@redhat.com)
+ * Fixed by Pekka Pietikainen (pp@ee.oulu.fi)
+ * Copyright (C) 2006 Broadcom Corporation.
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include <linux/ssb/ssb.h>
+#include <linux/ssb/ssb_regs.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+
+#include "ssb_private.h"
+
+
+/* Define the following to 1 to enable a printk on each coreswitch. */
+#define SSB_VERBOSE_PCICORESWITCH_DEBUG		0
+
+
+/* Lowlevel coreswitching */
+int ssb_pci_switch_coreidx(struct ssb_bus *bus, u8 coreidx)
+{
+	int err;
+	int attempts = 0;
+	u32 cur_core;
+
+	while (1) {
+		err = pci_write_config_dword(bus->host_pci, SSB_BAR0_WIN,
+					     (coreidx * SSB_CORE_SIZE)
+					     + SSB_ENUM_BASE);
+		if (err)
+			goto error;
+		err = pci_read_config_dword(bus->host_pci, SSB_BAR0_WIN,
+					    &cur_core);
+		if (err)
+			goto error;
+		cur_core = (cur_core - SSB_ENUM_BASE)
+			   / SSB_CORE_SIZE;
+		if (cur_core == coreidx)
+			break;
+
+		if (attempts++ > SSB_BAR0_MAX_RETRIES)
+			goto error;
+		udelay(10);
+	}
+	return 0;
+error:
+	ssb_printk(KERN_ERR PFX "Failed to switch to core %u\n", coreidx);
+	return -ENODEV;
+}
+
+int ssb_pci_switch_core(struct ssb_bus *bus,
+			struct ssb_device *dev)
+{
+	int err;
+	unsigned long flags;
+
+#if SSB_VERBOSE_PCICORESWITCH_DEBUG
+	ssb_printk(KERN_INFO PFX
+		   "Switching to %s core, index %d\n",
+		   ssb_core_name(dev->id.coreid),
+		   dev->core_index);
+#endif
+
+	spin_lock_irqsave(&bus->bar_lock, flags);
+	err = ssb_pci_switch_coreidx(bus, dev->core_index);
+	if (!err)
+		bus->mapped_device = dev;
+	spin_unlock_irqrestore(&bus->bar_lock, flags);
+
+	return err;
+}
+
+/* Enable/disable the on board crystal oscillator and/or PLL. */
+int ssb_pci_xtal(struct ssb_bus *bus, u32 what, int turn_on)
+{
+	int err;
+	u32 in, out, outenable;
+	u16 pci_status;
+
+	if (bus->bustype != SSB_BUSTYPE_PCI)
+		return 0;
+
+	err = pci_read_config_dword(bus->host_pci, SSB_GPIO_IN, &in);
+	if (err)
+		goto err_pci;
+	err = pci_read_config_dword(bus->host_pci, SSB_GPIO_OUT, &out);
+	if (err)
+		goto err_pci;
+	err = pci_read_config_dword(bus->host_pci, SSB_GPIO_OUT_ENABLE, &outenable);
+	if (err)
+		goto err_pci;
+
+	outenable |= what;
+
+	if (turn_on) {
+		/* Avoid glitching the clock if GPRS is already using it.
+		 * We can't actually read the state of the PLLPD so we infer it
+		 * by the value of XTAL_PU which *is* readable via gpioin.
+		 */
+		if (!(in & SSB_GPIO_XTAL)) {
+			if (what & SSB_GPIO_XTAL) {
+				/* Turn the crystal on */
+				out |= SSB_GPIO_XTAL;
+				if (what & SSB_GPIO_PLL)
+					out |= SSB_GPIO_PLL;
+				err = pci_write_config_dword(bus->host_pci, SSB_GPIO_OUT, out);
+				if (err)
+					goto err_pci;
+				err = pci_write_config_dword(bus->host_pci, SSB_GPIO_OUT_ENABLE,
+							     outenable);
+				if (err)
+					goto err_pci;
+				msleep(1);
+			}
+			if (what & SSB_GPIO_PLL) {
+				/* Turn the PLL on */
+				out &= ~SSB_GPIO_PLL;
+				err = pci_write_config_dword(bus->host_pci, SSB_GPIO_OUT, out);
+				if (err)
+					goto err_pci;
+				msleep(5);
+			}
+		}
+
+		err = pci_read_config_word(bus->host_pci, PCI_STATUS, &pci_status);
+		if (err)
+			goto err_pci;
+		pci_status &= ~PCI_STATUS_SIG_TARGET_ABORT;
+		err = pci_write_config_word(bus->host_pci, PCI_STATUS, pci_status);
+		if (err)
+			goto err_pci;
+	} else {
+		if (what & SSB_GPIO_XTAL) {
+			/* Turn the crystal off */
+			out &= ~SSB_GPIO_XTAL;
+		}
+		if (what & SSB_GPIO_PLL) {
+			/* Turn the PLL off */
+			out |= SSB_GPIO_PLL;
+		}
+		err = pci_write_config_dword(bus->host_pci, SSB_GPIO_OUT, out);
+		if (err)
+			goto err_pci;
+		err = pci_write_config_dword(bus->host_pci, SSB_GPIO_OUT_ENABLE, outenable);
+		if (err)
+			goto err_pci;
+	}
+
+out:
+	return err;
+
+err_pci:
+	printk(KERN_ERR PFX "Error: ssb_pci_xtal() could not access PCI config space!\n");
+	err = -EBUSY;
+	goto out;
+}
+
+/* Get the word-offset for a SSB_SPROM_XXX define. */
+#define SPOFF(offset)	(((offset) - SSB_SPROM_BASE) / sizeof(u16))
+/* Helper to extract some _offset, which is one of the SSB_SPROM_XXX defines. */
+#define SPEX(_outvar, _offset, _mask, _shift)	\
+	out->_outvar = ((in[SPOFF(_offset)] & (_mask)) >> (_shift))
+
+static inline u8 ssb_crc8(u8 crc, u8 data)
+{
+	/* Polynomial:   x^8 + x^7 + x^6 + x^4 + x^2 + 1   */
+	static const u8 t[] = {
+		0x00, 0xF7, 0xB9, 0x4E, 0x25, 0xD2, 0x9C, 0x6B,
+		0x4A, 0xBD, 0xF3, 0x04, 0x6F, 0x98, 0xD6, 0x21,
+		0x94, 0x63, 0x2D, 0xDA, 0xB1, 0x46, 0x08, 0xFF,
+		0xDE, 0x29, 0x67, 0x90, 0xFB, 0x0C, 0x42, 0xB5,
+		0x7F, 0x88, 0xC6, 0x31, 0x5A, 0xAD, 0xE3, 0x14,
+		0x35, 0xC2, 0x8C, 0x7B, 0x10, 0xE7, 0xA9, 0x5E,
+		0xEB, 0x1C, 0x52, 0xA5, 0xCE, 0x39, 0x77, 0x80,
+		0xA1, 0x56, 0x18, 0xEF, 0x84, 0x73, 0x3D, 0xCA,
+		0xFE, 0x09, 0x47, 0xB0, 0xDB, 0x2C, 0x62, 0x95,
+		0xB4, 0x43, 0x0D, 0xFA, 0x91, 0x66, 0x28, 0xDF,
+		0x6A, 0x9D, 0xD3, 0x24, 0x4F, 0xB8, 0xF6, 0x01,
+		0x20, 0xD7, 0x99, 0x6E, 0x05, 0xF2, 0xBC, 0x4B,
+		0x81, 0x76, 0x38, 0xCF, 0xA4, 0x53, 0x1D, 0xEA,
+		0xCB, 0x3C, 0x72, 0x85, 0xEE, 0x19, 0x57, 0xA0,
+		0x15, 0xE2, 0xAC, 0x5B, 0x30, 0xC7, 0x89, 0x7E,
+		0x5F, 0xA8, 0xE6, 0x11, 0x7A, 0x8D, 0xC3, 0x34,
+		0xAB, 0x5C, 0x12, 0xE5, 0x8E, 0x79, 0x37, 0xC0,
+		0xE1, 0x16, 0x58, 0xAF, 0xC4, 0x33, 0x7D, 0x8A,
+		0x3F, 0xC8, 0x86, 0x71, 0x1A, 0xED, 0xA3, 0x54,
+		0x75, 0x82, 0xCC, 0x3B, 0x50, 0xA7, 0xE9, 0x1E,
+		0xD4, 0x23, 0x6D, 0x9A, 0xF1, 0x06, 0x48, 0xBF,
+		0x9E, 0x69, 0x27, 0xD0, 0xBB, 0x4C, 0x02, 0xF5,
+		0x40, 0xB7, 0xF9, 0x0E, 0x65, 0x92, 0xDC, 0x2B,
+		0x0A, 0xFD, 0xB3, 0x44, 0x2F, 0xD8, 0x96, 0x61,
+		0x55, 0xA2, 0xEC, 0x1B, 0x70, 0x87, 0xC9, 0x3E,
+		0x1F, 0xE8, 0xA6, 0x51, 0x3A, 0xCD, 0x83, 0x74,
+		0xC1, 0x36, 0x78, 0x8F, 0xE4, 0x13, 0x5D, 0xAA,
+		0x8B, 0x7C, 0x32, 0xC5, 0xAE, 0x59, 0x17, 0xE0,
+		0x2A, 0xDD, 0x93, 0x64, 0x0F, 0xF8, 0xB6, 0x41,
+		0x60, 0x97, 0xD9, 0x2E, 0x45, 0xB2, 0xFC, 0x0B,
+		0xBE, 0x49, 0x07, 0xF0, 0x9B, 0x6C, 0x22, 0xD5,
+		0xF4, 0x03, 0x4D, 0xBA, 0xD1, 0x26, 0x68, 0x9F,
+	};
+	return t[crc ^ data];
+}
+
+static u8 ssb_sprom_crc(const u16 *sprom)
+{
+	int word;
+	u8 crc = 0xFF;
+
+	for (word = 0; word < SSB_SPROMSIZE_WORDS - 1; word++) {
+		crc = ssb_crc8(crc, sprom[word] & 0x00FF);
+		crc = ssb_crc8(crc, (sprom[word] & 0xFF00) >> 8);
+	}
+	crc = ssb_crc8(crc, sprom[SPOFF(SSB_SPROM_REVISION)] & 0x00FF);
+	crc ^= 0xFF;
+
+	return crc;
+}
+
+static int sprom_check_crc(const u16 *sprom)
+{
+	u8 crc;
+	u8 expected_crc;
+	u16 tmp;
+
+	crc = ssb_sprom_crc(sprom);
+	tmp = sprom[SPOFF(SSB_SPROM_REVISION)] & SSB_SPROM_REVISION_CRC;
+	expected_crc = tmp >> SSB_SPROM_REVISION_CRC_SHIFT;
+	if (crc != expected_crc)
+		return -EPROTO;
+
+	return 0;
+}
+
+static void sprom_do_read(struct ssb_bus *bus, u16 *sprom)
+{
+	int i;
+
+	for (i = 0; i < SSB_SPROMSIZE_WORDS; i++)
+		sprom[i] = readw(bus->mmio + SSB_SPROM_BASE + (i * 2));
+}
+
+static int sprom_do_write(struct ssb_bus *bus, const u16 *sprom)
+{
+	struct pci_dev *pdev = bus->host_pci;
+	int i, err;
+	u32 spromctl;
+
+	ssb_printk(KERN_NOTICE PFX "Writing SPROM. Do NOT turn off the power! Please stand by...\n");
+	err = pci_read_config_dword(pdev, SSB_SPROMCTL, &spromctl);
+	if (err)
+		goto err_ctlreg;
+	spromctl |= SSB_SPROMCTL_WE;
+	err = pci_write_config_dword(pdev, SSB_SPROMCTL, spromctl);
+	if (err)
+		goto err_ctlreg;
+	ssb_printk(KERN_NOTICE PFX "[ 0%%");
+	msleep(500);
+	for (i = 0; i < SSB_SPROMSIZE_WORDS; i++) {
+		if (i == SSB_SPROMSIZE_WORDS / 4)
+			ssb_printk("25%%");
+		else if (i == SSB_SPROMSIZE_WORDS / 2)
+			ssb_printk("50%%");
+		else if (i == (SSB_SPROMSIZE_WORDS / 4) * 3)
+			ssb_printk("75%%");
+		else if (i % 2)
+			ssb_printk(".");
+		writew(sprom[i], bus->mmio + SSB_SPROM_BASE + (i * 2));
+		mmiowb();
+		msleep(20);
+	}
+	err = pci_read_config_dword(pdev, SSB_SPROMCTL, &spromctl);
+	if (err)
+		goto err_ctlreg;
+	spromctl &= ~SSB_SPROMCTL_WE;
+	err = pci_write_config_dword(pdev, SSB_SPROMCTL, spromctl);
+	if (err)
+		goto err_ctlreg;
+	msleep(500);
+	ssb_printk("100%% ]\n");
+	ssb_printk(KERN_NOTICE PFX "SPROM written.\n");
+
+	return 0;
+err_ctlreg:
+	ssb_printk(KERN_ERR PFX "Could not access SPROM control register.\n");
+	return err;
+}
+
+static void sprom_extract_r1(struct ssb_sprom_r1 *out, const u16 *in)
+{
+	int i;
+	u16 v;
+
+	SPEX(pci_spid, SSB_SPROM1_SPID, 0xFFFF, 0);
+	SPEX(pci_svid, SSB_SPROM1_SVID, 0xFFFF, 0);
+	SPEX(pci_pid, SSB_SPROM1_PID, 0xFFFF, 0);
+	for (i = 0; i < 3; i++) {
+		v = in[SPOFF(SSB_SPROM1_IL0MAC) + i];
+		*(((u16 *)out->il0mac) + i) = cpu_to_be16(v);
+	}
+	for (i = 0; i < 3; i++) {
+		v = in[SPOFF(SSB_SPROM1_ET0MAC) + i];
+		*(((u16 *)out->et0mac) + i) = cpu_to_be16(v);
+	}
+	for (i = 0; i < 3; i++) {
+		v = in[SPOFF(SSB_SPROM1_ET1MAC) + i];
+		*(((u16 *)out->et1mac) + i) = cpu_to_be16(v);
+	}
+	SPEX(et0phyaddr, SSB_SPROM1_ETHPHY, SSB_SPROM1_ETHPHY_ET0A, 0);
+	SPEX(et1phyaddr, SSB_SPROM1_ETHPHY, SSB_SPROM1_ETHPHY_ET1A,
+	     SSB_SPROM1_ETHPHY_ET1A_SHIFT);
+	SPEX(et0mdcport, SSB_SPROM1_ETHPHY, SSB_SPROM1_ETHPHY_ET0M, 14);
+	SPEX(et1mdcport, SSB_SPROM1_ETHPHY, SSB_SPROM1_ETHPHY_ET1M, 15);
+	SPEX(board_rev, SSB_SPROM1_BINF, SSB_SPROM1_BINF_BREV, 0);
+	SPEX(country_code, SSB_SPROM1_BINF, SSB_SPROM1_BINF_CCODE,
+	     SSB_SPROM1_BINF_CCODE_SHIFT);
+	SPEX(antenna_a, SSB_SPROM1_BINF, SSB_SPROM1_BINF_ANTA,
+	     SSB_SPROM1_BINF_ANTA_SHIFT);
+	SPEX(antenna_bg, SSB_SPROM1_BINF, SSB_SPROM1_BINF_ANTBG,
+	     SSB_SPROM1_BINF_ANTBG_SHIFT);
+	SPEX(pa0b0, SSB_SPROM1_PA0B0, 0xFFFF, 0);
+	SPEX(pa0b1, SSB_SPROM1_PA0B1, 0xFFFF, 0);
+	SPEX(pa0b2, SSB_SPROM1_PA0B2, 0xFFFF, 0);
+	SPEX(pa1b0, SSB_SPROM1_PA1B0, 0xFFFF, 0);
+	SPEX(pa1b1, SSB_SPROM1_PA1B1, 0xFFFF, 0);
+	SPEX(pa1b2, SSB_SPROM1_PA1B2, 0xFFFF, 0);
+	SPEX(gpio0, SSB_SPROM1_GPIOA, SSB_SPROM1_GPIOA_P0, 0);
+	SPEX(gpio1, SSB_SPROM1_GPIOA, SSB_SPROM1_GPIOA_P1,
+	     SSB_SPROM1_GPIOA_P1_SHIFT);
+	SPEX(gpio2, SSB_SPROM1_GPIOB, SSB_SPROM1_GPIOB_P2, 0);
+	SPEX(gpio3, SSB_SPROM1_GPIOB, SSB_SPROM1_GPIOB_P3,
+	     SSB_SPROM1_GPIOB_P3_SHIFT);
+	SPEX(maxpwr_a, SSB_SPROM1_MAXPWR, SSB_SPROM1_MAXPWR_A,
+	     SSB_SPROM1_MAXPWR_A_SHIFT);
+	SPEX(maxpwr_bg, SSB_SPROM1_MAXPWR, SSB_SPROM1_MAXPWR_BG, 0);
+	SPEX(itssi_a, SSB_SPROM1_ITSSI, SSB_SPROM1_ITSSI_A,
+	     SSB_SPROM1_ITSSI_A_SHIFT);
+	SPEX(itssi_bg, SSB_SPROM1_ITSSI, SSB_SPROM1_ITSSI_BG, 0);
+	SPEX(boardflags_lo, SSB_SPROM1_BFLLO, 0xFFFF, 0);
+	SPEX(antenna_gain_a, SSB_SPROM1_AGAIN, SSB_SPROM1_AGAIN_A, 0);
+	SPEX(antenna_gain_bg, SSB_SPROM1_AGAIN, SSB_SPROM1_AGAIN_BG,
+	     SSB_SPROM1_AGAIN_BG_SHIFT);
+	for (i = 0; i < 4; i++) {
+		v = in[SPOFF(SSB_SPROM1_OEM) + i];
+		*(((u16 *)out->oem) + i) = cpu_to_le16(v);
+	}
+}
+
+static void sprom_extract_r2(struct ssb_sprom_r2 *out, const u16 *in)
+{
+	int i;
+	u16 v;
+
+	SPEX(boardflags_hi, SSB_SPROM2_BFLHI,  0xFFFF, 0);
+	SPEX(maxpwr_a_hi, SSB_SPROM2_MAXP_A, SSB_SPROM2_MAXP_A_HI, 0);
+	SPEX(maxpwr_a_lo, SSB_SPROM2_MAXP_A, SSB_SPROM2_MAXP_A_LO,
+	     SSB_SPROM2_MAXP_A_LO_SHIFT);
+	SPEX(pa1lob0, SSB_SPROM2_PA1LOB0, 0xFFFF, 0);
+	SPEX(pa1lob1, SSB_SPROM2_PA1LOB1, 0xFFFF, 0);
+	SPEX(pa1lob2, SSB_SPROM2_PA1LOB2, 0xFFFF, 0);
+	SPEX(pa1hib0, SSB_SPROM2_PA1HIB0, 0xFFFF, 0);
+	SPEX(pa1hib1, SSB_SPROM2_PA1HIB1, 0xFFFF, 0);
+	SPEX(pa1hib2, SSB_SPROM2_PA1HIB2, 0xFFFF, 0);
+	SPEX(ofdm_pwr_off, SSB_SPROM2_OPO, SSB_SPROM2_OPO_VALUE, 0);
+	for (i = 0; i < 4; i++) {
+		v = in[SPOFF(SSB_SPROM2_CCODE) + i];
+		*(((u16 *)out->country_str) + i) = cpu_to_le16(v);
+	}
+}
+
+static void sprom_extract_r3(struct ssb_sprom_r3 *out, const u16 *in)
+{
+	out->ofdmapo  = (in[SPOFF(SSB_SPROM3_OFDMAPO) + 0] & 0xFF00) >> 8;
+	out->ofdmapo |= (in[SPOFF(SSB_SPROM3_OFDMAPO) + 0] & 0x00FF) << 8;
+	out->ofdmapo <<= 16;
+	out->ofdmapo |= (in[SPOFF(SSB_SPROM3_OFDMAPO) + 1] & 0xFF00) >> 8;
+	out->ofdmapo |= (in[SPOFF(SSB_SPROM3_OFDMAPO) + 1] & 0x00FF) << 8;
+
+	out->ofdmalpo  = (in[SPOFF(SSB_SPROM3_OFDMALPO) + 0] & 0xFF00) >> 8;
+	out->ofdmalpo |= (in[SPOFF(SSB_SPROM3_OFDMALPO) + 0] & 0x00FF) << 8;
+	out->ofdmalpo <<= 16;
+	out->ofdmalpo |= (in[SPOFF(SSB_SPROM3_OFDMALPO) + 1] & 0xFF00) >> 8;
+	out->ofdmalpo |= (in[SPOFF(SSB_SPROM3_OFDMALPO) + 1] & 0x00FF) << 8;
+
+	out->ofdmahpo  = (in[SPOFF(SSB_SPROM3_OFDMAHPO) + 0] & 0xFF00) >> 8;
+	out->ofdmahpo |= (in[SPOFF(SSB_SPROM3_OFDMAHPO) + 0] & 0x00FF) << 8;
+	out->ofdmahpo <<= 16;
+	out->ofdmahpo |= (in[SPOFF(SSB_SPROM3_OFDMAHPO) + 1] & 0xFF00) >> 8;
+	out->ofdmahpo |= (in[SPOFF(SSB_SPROM3_OFDMAHPO) + 1] & 0x00FF) << 8;
+
+	SPEX(gpioldc_on_cnt, SSB_SPROM3_GPIOLDC, SSB_SPROM3_GPIOLDC_ON,
+	     SSB_SPROM3_GPIOLDC_ON_SHIFT);
+	SPEX(gpioldc_off_cnt, SSB_SPROM3_GPIOLDC, SSB_SPROM3_GPIOLDC_OFF,
+	     SSB_SPROM3_GPIOLDC_OFF_SHIFT);
+	SPEX(cckpo_1M, SSB_SPROM3_CCKPO, SSB_SPROM3_CCKPO_1M, 0);
+	SPEX(cckpo_2M, SSB_SPROM3_CCKPO, SSB_SPROM3_CCKPO_2M,
+	     SSB_SPROM3_CCKPO_2M_SHIFT);
+	SPEX(cckpo_55M, SSB_SPROM3_CCKPO, SSB_SPROM3_CCKPO_55M,
+	     SSB_SPROM3_CCKPO_55M_SHIFT);
+	SPEX(cckpo_11M, SSB_SPROM3_CCKPO, SSB_SPROM3_CCKPO_11M,
+	     SSB_SPROM3_CCKPO_11M_SHIFT);
+
+	out->ofdmgpo  = (in[SPOFF(SSB_SPROM3_OFDMGPO) + 0] & 0xFF00) >> 8;
+	out->ofdmgpo |= (in[SPOFF(SSB_SPROM3_OFDMGPO) + 0] & 0x00FF) << 8;
+	out->ofdmgpo <<= 16;
+	out->ofdmgpo |= (in[SPOFF(SSB_SPROM3_OFDMGPO) + 1] & 0xFF00) >> 8;
+	out->ofdmgpo |= (in[SPOFF(SSB_SPROM3_OFDMGPO) + 1] & 0x00FF) << 8;
+}
+
+static int sprom_extract(struct ssb_bus *bus,
+			 struct ssb_sprom *out, const u16 *in)
+{
+	memset(out, 0, sizeof(*out));
+
+	SPEX(revision, SSB_SPROM_REVISION, SSB_SPROM_REVISION_REV, 0);
+	SPEX(crc, SSB_SPROM_REVISION, SSB_SPROM_REVISION_CRC,
+	     SSB_SPROM_REVISION_CRC_SHIFT);
+
+	if ((bus->chip_id & 0xFF00) == 0x4400) {
+		/* Workaround: The BCM44XX chip has a stupid revision
+		 * number stored in the SPROM.
+		 * Always extract r1. */
+		sprom_extract_r1(&out->r1, in);
+	} else {
+		if (out->revision == 0)
+			goto unsupported;
+		if (out->revision >= 1 && out->revision <= 3)
+			sprom_extract_r1(&out->r1, in);
+		if (out->revision >= 2 && out->revision <= 3)
+			sprom_extract_r2(&out->r2, in);
+		if (out->revision == 3)
+			sprom_extract_r3(&out->r3, in);
+		if (out->revision >= 4)
+			goto unsupported;
+	}
+
+	return 0;
+unsupported:
+	ssb_printk(KERN_WARNING PFX "Unsupported SPROM revision %d "
+		   "detected. Will extract v1\n", out->revision);
+	sprom_extract_r1(&out->r1, in);
+	return 0;
+}
+
+static int ssb_pci_sprom_get(struct ssb_bus *bus,
+			     struct ssb_sprom *sprom)
+{
+	int err = -ENOMEM;
+	u16 *buf;
+
+	buf = kcalloc(SSB_SPROMSIZE_WORDS, sizeof(u16), GFP_KERNEL);
+	if (!buf)
+		goto out;
+	sprom_do_read(bus, buf);
+	err = sprom_check_crc(buf);
+	if (err) {
+		ssb_printk(KERN_WARNING PFX
+			   "WARNING: Invalid SPROM CRC (corrupt SPROM)\n");
+	}
+	err = sprom_extract(bus, sprom, buf);
+
+	kfree(buf);
+out:
+	return err;
+}
+
+static void ssb_pci_get_boardinfo(struct ssb_bus *bus,
+				  struct ssb_boardinfo *bi)
+{
+	pci_read_config_word(bus->host_pci, PCI_SUBSYSTEM_VENDOR_ID,
+			     &bi->vendor);
+	pci_read_config_word(bus->host_pci, PCI_SUBSYSTEM_ID,
+			     &bi->type);
+	pci_read_config_word(bus->host_pci, PCI_REVISION_ID,
+			     &bi->rev);
+}
+
+int ssb_pci_get_invariants(struct ssb_bus *bus,
+			   struct ssb_init_invariants *iv)
+{
+	int err;
+
+	err = ssb_pci_sprom_get(bus, &iv->sprom);
+	if (err)
+		goto out;
+	ssb_pci_get_boardinfo(bus, &iv->boardinfo);
+
+out:
+	return err;
+}
+
+#ifdef CONFIG_SSB_DEBUG
+static int ssb_pci_assert_buspower(struct ssb_bus *bus)
+{
+	if (likely(bus->powered_up))
+		return 0;
+
+	printk(KERN_ERR PFX "FATAL ERROR: Bus powered down "
+	       "while accessing PCI MMIO space\n");
+	if (bus->power_warn_count <= 10) {
+		bus->power_warn_count++;
+		dump_stack();
+	}
+
+	return -ENODEV;
+}
+#else /* DEBUG */
+static inline int ssb_pci_assert_buspower(struct ssb_bus *bus)
+{
+	return 0;
+}
+#endif /* DEBUG */
+
+static u16 ssb_pci_read16(struct ssb_device *dev, u16 offset)
+{
+	struct ssb_bus *bus = dev->bus;
+
+	if (unlikely(ssb_pci_assert_buspower(bus)))
+		return 0xFFFF;
+	if (unlikely(bus->mapped_device != dev)) {
+		if (unlikely(ssb_pci_switch_core(bus, dev)))
+			return 0xFFFF;
+	}
+	return readw(bus->mmio + offset);
+}
+
+static u32 ssb_pci_read32(struct ssb_device *dev, u16 offset)
+{
+	struct ssb_bus *bus = dev->bus;
+
+	if (unlikely(ssb_pci_assert_buspower(bus)))
+		return 0xFFFFFFFF;
+	if (unlikely(bus->mapped_device != dev)) {
+		if (unlikely(ssb_pci_switch_core(bus, dev)))
+			return 0xFFFFFFFF;
+	}
+	return readl(bus->mmio + offset);
+}
+
+static void ssb_pci_write16(struct ssb_device *dev, u16 offset, u16 value)
+{
+	struct ssb_bus *bus = dev->bus;
+
+	if (unlikely(ssb_pci_assert_buspower(bus)))
+		return;
+	if (unlikely(bus->mapped_device != dev)) {
+		if (unlikely(ssb_pci_switch_core(bus, dev)))
+			return;
+	}
+	writew(value, bus->mmio + offset);
+}
+
+static void ssb_pci_write32(struct ssb_device *dev, u16 offset, u32 value)
+{
+	struct ssb_bus *bus = dev->bus;
+
+	if (unlikely(ssb_pci_assert_buspower(bus)))
+		return;
+	if (unlikely(bus->mapped_device != dev)) {
+		if (unlikely(ssb_pci_switch_core(bus, dev)))
+			return;
+	}
+	writel(value, bus->mmio + offset);
+}
+
+/* Not "static", as it's used in main.c */
+const struct ssb_bus_ops ssb_pci_ops = {
+	.read16		= ssb_pci_read16,
+	.read32		= ssb_pci_read32,
+	.write16	= ssb_pci_write16,
+	.write32	= ssb_pci_write32,
+};
+
+static int sprom2hex(const u16 *sprom, char *buf, size_t buf_len)
+{
+	int i, pos = 0;
+
+	for (i = 0; i < SSB_SPROMSIZE_WORDS; i++) {
+		pos += snprintf(buf + pos, buf_len - pos - 1,
+				"%04X", swab16(sprom[i]) & 0xFFFF);
+	}
+	pos += snprintf(buf + pos, buf_len - pos - 1, "\n");
+
+	return pos + 1;
+}
+
+static int hex2sprom(u16 *sprom, const char *dump, size_t len)
+{
+	char tmp[5] = { 0 };
+	int cnt = 0;
+	unsigned long parsed;
+
+	if (len < SSB_SPROMSIZE_BYTES * 2)
+		return -EINVAL;
+
+	while (cnt < SSB_SPROMSIZE_WORDS) {
+		memcpy(tmp, dump, 4);
+		dump += 4;
+		parsed = simple_strtoul(tmp, NULL, 16);
+		sprom[cnt++] = swab16((u16)parsed);
+	}
+
+	return 0;
+}
+
+static ssize_t ssb_pci_attr_sprom_show(struct device *pcidev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	struct pci_dev *pdev = container_of(pcidev, struct pci_dev, dev);
+	struct ssb_bus *bus;
+	u16 *sprom;
+	int err = -ENODEV;
+	ssize_t count = 0;
+
+	bus = ssb_pci_dev_to_bus(pdev);
+	if (!bus)
+		goto out;
+	err = -ENOMEM;
+	sprom = kcalloc(SSB_SPROMSIZE_WORDS, sizeof(u16), GFP_KERNEL);
+	if (!sprom)
+		goto out;
+
+	/* Use interruptible locking, as the SPROM write might
+	 * be holding the lock for several seconds. So allow userspace
+	 * to cancel operation. */
+	err = -ERESTARTSYS;
+	if (mutex_lock_interruptible(&bus->pci_sprom_mutex))
+		goto out_kfree;
+	sprom_do_read(bus, sprom);
+	mutex_unlock(&bus->pci_sprom_mutex);
+
+	count = sprom2hex(sprom, buf, PAGE_SIZE);
+	err = 0;
+
+out_kfree:
+	kfree(sprom);
+out:
+	return err ? err : count;
+}
+
+static ssize_t ssb_pci_attr_sprom_store(struct device *pcidev,
+					struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct pci_dev *pdev = container_of(pcidev, struct pci_dev, dev);
+	struct ssb_bus *bus;
+	u16 *sprom;
+	int res = 0, err = -ENODEV;
+
+	bus = ssb_pci_dev_to_bus(pdev);
+	if (!bus)
+		goto out;
+	err = -ENOMEM;
+	sprom = kcalloc(SSB_SPROMSIZE_WORDS, sizeof(u16), GFP_KERNEL);
+	if (!sprom)
+		goto out;
+	err = hex2sprom(sprom, buf, count);
+	if (err) {
+		err = -EINVAL;
+		goto out_kfree;
+	}
+	err = sprom_check_crc(sprom);
+	if (err) {
+		err = -EINVAL;
+		goto out_kfree;
+	}
+
+	/* Use interruptible locking, as the SPROM write might
+	 * be holding the lock for several seconds. So allow userspace
+	 * to cancel operation. */
+	err = -ERESTARTSYS;
+	if (mutex_lock_interruptible(&bus->pci_sprom_mutex))
+		goto out_kfree;
+	err = ssb_devices_freeze(bus);
+	if (err == -EOPNOTSUPP) {
+		ssb_printk(KERN_ERR PFX "SPROM write: Could not freeze devices. "
+			   "No suspend support. Is CONFIG_PM enabled?\n");
+		goto out_unlock;
+	}
+	if (err) {
+		ssb_printk(KERN_ERR PFX "SPROM write: Could not freeze all devices\n");
+		goto out_unlock;
+	}
+	res = sprom_do_write(bus, sprom);
+	err = ssb_devices_thaw(bus);
+	if (err)
+		ssb_printk(KERN_ERR PFX "SPROM write: Could not thaw all devices\n");
+out_unlock:
+	mutex_unlock(&bus->pci_sprom_mutex);
+out_kfree:
+	kfree(sprom);
+out:
+	if (res)
+		return res;
+	return err ? err : count;
+}
+
+static DEVICE_ATTR(ssb_sprom, 0600,
+		   ssb_pci_attr_sprom_show,
+		   ssb_pci_attr_sprom_store);
+
+void ssb_pci_exit(struct ssb_bus *bus)
+{
+	struct pci_dev *pdev;
+
+	if (bus->bustype != SSB_BUSTYPE_PCI)
+		return;
+
+	pdev = bus->host_pci;
+	device_remove_file(&pdev->dev, &dev_attr_ssb_sprom);
+}
+
+int ssb_pci_init(struct ssb_bus *bus)
+{
+	struct pci_dev *pdev;
+	int err;
+
+	if (bus->bustype != SSB_BUSTYPE_PCI)
+		return 0;
+
+	pdev = bus->host_pci;
+	mutex_init(&bus->pci_sprom_mutex);
+	err = device_create_file(&pdev->dev, &dev_attr_ssb_sprom);
+	if (err)
+		goto out;
+
+out:
+	return err;
+}