bcma: add Broadcom specific AMBA bus driver

Broadcom has released cards based on a new AMBA-based bus type. From a
programming point of view, this new bus type differs from AMBA and does
not use AMBA common registers. It also differs enough from SSB. We
decided that a new bus driver is needed to keep the code clean.

In its current form, the driver detects devices present on the bus and
registers them in the system. It allows registering BCMA drivers for
specified bus devices and provides them basic operations. The bus driver
itself includes two important bus managing drivers: ChipCommon core
driver and PCI(c) core driver. They are early used to allow correct
initialization.

Currently code is limited to supporting buses on PCI(e) devices, however
the driver is designed to be used also on other hosts. The host
abstraction layer is implemented and already used for PCI(e).

Support for PCI(e) hosts is working and seems to be stable (access to
80211 core was tested successfully on a few devices). We can still
optimize it by using some fixed windows, but this can be done later
without affecting any external code. Windows are just ranges in MMIO
used for accessing cores on the bus.

Cc: Greg KH <greg@kroah.com>
Cc: Michael Büsch <mb@bu3sch.de>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: George Kashperko <george@znau.edu.ua>
Cc: Arend van Spriel <arend@broadcom.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Botting <andy@andybotting.com>
Cc: linuxdriverproject <devel@linuxdriverproject.org>
Cc: linux-kernel@vger.kernel.org <linux-kernel@vger.kernel.org>
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 163 insertions, 0 deletions

diff --git a/drivers/bcma/driver_pci.c b/drivers/bcma/driver_pci.c
new file mode 100644
index 000000000000..b98b8359bef5
--- /dev/null
+++ b/drivers/bcma/driver_pci.c
@@ -0,0 +1,163 @@
+/*
+ * Broadcom specific AMBA
+ * PCI Core
+ *
+ * Copyright 2005, Broadcom Corporation
+ * Copyright 2006, 2007, Michael Buesch <mb@bu3sch.de>
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include "bcma_private.h"
+#include <linux/bcma/bcma.h>
+
+/**************************************************
+ * R/W ops.
+ **************************************************/
+
+static u32 bcma_pcie_read(struct bcma_drv_pci *pc, u32 address)
+{
+        pcicore_write32(pc, 0x130, address);
+        pcicore_read32(pc, 0x130);
+        return pcicore_read32(pc, 0x134);
+}
+
+#if 0
+static void bcma_pcie_write(struct bcma_drv_pci *pc, u32 address, u32 data)
+{
+        pcicore_write32(pc, 0x130, address);
+        pcicore_read32(pc, 0x130);
+        pcicore_write32(pc, 0x134, data);
+}
+#endif
+
+static void bcma_pcie_mdio_set_phy(struct bcma_drv_pci *pc, u8 phy)
+{
+        const u16 mdio_control = 0x128;
+        const u16 mdio_data = 0x12C;
+        u32 v;
+        int i;
+
+        v = (1 << 30); /* Start of Transaction */
+        v |= (1 << 28); /* Write Transaction */
+        v |= (1 << 17); /* Turnaround */
+        v |= (0x1F << 18);
+        v |= (phy << 4);
+        pcicore_write32(pc, mdio_data, v);
+
+        udelay(10);
+        for (i = 0; i < 200; i++) {
+                v = pcicore_read32(pc, mdio_control);
+                if (v & 0x100 /* Trans complete */)
+                        break;
+                msleep(1);
+        }
+}
+
+static u16 bcma_pcie_mdio_read(struct bcma_drv_pci *pc, u8 device, u8 address)
+{
+        const u16 mdio_control = 0x128;
+        const u16 mdio_data = 0x12C;
+        int max_retries = 10;
+        u16 ret = 0;
+        u32 v;
+        int i;
+
+        v = 0x80; /* Enable Preamble Sequence */
+        v |= 0x2; /* MDIO Clock Divisor */
+        pcicore_write32(pc, mdio_control, v);
+
+        if (pc->core->id.rev >= 10) {
+                max_retries = 200;
+                bcma_pcie_mdio_set_phy(pc, device);
+        }
+
+        v = (1 << 30); /* Start of Transaction */
+        v |= (1 << 29); /* Read Transaction */
+        v |= (1 << 17); /* Turnaround */
+        if (pc->core->id.rev < 10)
+                v |= (u32)device << 22;
+        v |= (u32)address << 18;
+        pcicore_write32(pc, mdio_data, v);
+        /* Wait for the device to complete the transaction */
+        udelay(10);
+        for (i = 0; i < 200; i++) {
+                v = pcicore_read32(pc, mdio_control);
+                if (v & 0x100 /* Trans complete */) {
+                        udelay(10);
+                        ret = pcicore_read32(pc, mdio_data);
+                        break;
+                }
+                msleep(1);
+        }
+        pcicore_write32(pc, mdio_control, 0);
+        return ret;
+}
+
+static void bcma_pcie_mdio_write(struct bcma_drv_pci *pc, u8 device,
+                                u8 address, u16 data)
+{
+        const u16 mdio_control = 0x128;
+        const u16 mdio_data = 0x12C;
+        int max_retries = 10;
+        u32 v;
+        int i;
+
+        v = 0x80; /* Enable Preamble Sequence */
+        v |= 0x2; /* MDIO Clock Divisor */
+        pcicore_write32(pc, mdio_control, v);
+
+        if (pc->core->id.rev >= 10) {
+                max_retries = 200;
+                bcma_pcie_mdio_set_phy(pc, device);
+        }
+
+        v = (1 << 30); /* Start of Transaction */
+        v |= (1 << 28); /* Write Transaction */
+        v |= (1 << 17); /* Turnaround */
+        if (pc->core->id.rev < 10)
+                v |= (u32)device << 22;
+        v |= (u32)address << 18;
+        v |= data;
+        pcicore_write32(pc, mdio_data, v);
+        /* Wait for the device to complete the transaction */
+        udelay(10);
+        for (i = 0; i < max_retries; i++) {
+                v = pcicore_read32(pc, mdio_control);
+                if (v & 0x100 /* Trans complete */)
+                        break;
+                msleep(1);
+        }
+        pcicore_write32(pc, mdio_control, 0);
+}
+
+/**************************************************
+ * Workarounds.
+ **************************************************/
+
+static u8 bcma_pcicore_polarity_workaround(struct bcma_drv_pci *pc)
+{
+        return (bcma_pcie_read(pc, 0x204) & 0x10) ? 0xC0 : 0x80;
+}
+
+static void bcma_pcicore_serdes_workaround(struct bcma_drv_pci *pc)
+{
+        const u8 serdes_pll_device = 0x1D;
+        const u8 serdes_rx_device = 0x1F;
+        u16 tmp;
+
+        bcma_pcie_mdio_write(pc, serdes_rx_device, 1 /* Control */,
+                              bcma_pcicore_polarity_workaround(pc));
+        tmp = bcma_pcie_mdio_read(pc, serdes_pll_device, 1 /* Control */);
+        if (tmp & 0x4000)
+                bcma_pcie_mdio_write(pc, serdes_pll_device, 1, tmp & ~0x4000);
+}
+
+/**************************************************
+ * Init.
+ **************************************************/
+
+void bcma_core_pci_init(struct bcma_drv_pci *pc)
+{
+        bcma_pcicore_serdes_workaround(pc);
+}