USB: Add EHCI and OHCH glue for OCTEON II SOCs.

The OCTEON II SOC has USB EHCI and OHCI controllers connected directly
to the internal I/O bus.  This patch adds the necessary 'glue' logic
to allow ehci-hcd and ohci-hcd drivers to work on OCTEON II.

The OCTEON normally runs big-endian, and the ehci/ohci internal
registers have host endianness, so we need to select
USB_EHCI_BIG_ENDIAN_MMIO.

The ehci and ohci blocks share a common clocking and PHY
infrastructure.  Initialization of the host controller and PHY clocks
is common between the two and is factored out into the
octeon2-common.c file.

Setting of USB_ARCH_HAS_OHCI and USB_ARCH_HAS_EHCI is done in
arch/mips/Kconfig in a following patch.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-usb@vger.kernel.org
To: dbrownell@users.sourceforge.net
Patchwork: http://patchwork.linux-mips.org/patch/1675/
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 185 insertions, 0 deletions

diff --git a/drivers/usb/host/octeon2-common.c b/drivers/usb/host/octeon2-common.c
new file mode 100644
index 000000000000..72d672cfcf39
--- /dev/null
+++ b/drivers/usb/host/octeon2-common.c
@@ -0,0 +1,185 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2010 Cavium Networks
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+
+#include <asm/atomic.h>
+
+#include <asm/octeon/octeon.h>
+#include <asm/octeon/cvmx-uctlx-defs.h>
+
+static atomic_t  octeon2_usb_clock_start_cnt = ATOMIC_INIT(0);
+
+void octeon2_usb_clocks_start(void)
+{
+	u64 div;
+	union cvmx_uctlx_if_ena if_ena;
+	union cvmx_uctlx_clk_rst_ctl clk_rst_ctl;
+	union cvmx_uctlx_uphy_ctl_status uphy_ctl_status;
+	union cvmx_uctlx_uphy_portx_ctl_status port_ctl_status;
+	int i;
+	unsigned long io_clk_64_to_ns;
+
+	if (atomic_inc_return(&octeon2_usb_clock_start_cnt) != 1)
+		return;
+
+	io_clk_64_to_ns = 64000000000ull / octeon_get_io_clock_rate();
+
+	/*
+	 * Step 1: Wait for voltages stable.  That surely happened
+	 * before starting the kernel.
+	 *
+	 * Step 2: Enable  SCLK of UCTL by writing UCTL0_IF_ENA[EN] = 1
+	 */
+	if_ena.u64 = 0;
+	if_ena.s.en = 1;
+	cvmx_write_csr(CVMX_UCTLX_IF_ENA(0), if_ena.u64);
+
+	/* Step 3: Configure the reference clock, PHY, and HCLK */
+	clk_rst_ctl.u64 = cvmx_read_csr(CVMX_UCTLX_CLK_RST_CTL(0));
+	/* 3a */
+	clk_rst_ctl.s.p_por = 1;
+	clk_rst_ctl.s.hrst = 0;
+	clk_rst_ctl.s.p_prst = 0;
+	clk_rst_ctl.s.h_clkdiv_rst = 0;
+	clk_rst_ctl.s.o_clkdiv_rst = 0;
+	clk_rst_ctl.s.h_clkdiv_en = 0;
+	clk_rst_ctl.s.o_clkdiv_en = 0;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+
+	/* 3b */
+	/* 12MHz crystal. */
+	clk_rst_ctl.s.p_refclk_sel = 0;
+	clk_rst_ctl.s.p_refclk_div = 0;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+
+	/* 3c */
+	div = octeon_get_io_clock_rate() / 130000000ull;
+
+	switch (div) {
+	case 0:
+		div = 1;
+		break;
+	case 1:
+	case 2:
+	case 3:
+	case 4:
+		break;
+	case 5:
+		div = 4;
+		break;
+	case 6:
+	case 7:
+		div = 6;
+		break;
+	case 8:
+	case 9:
+	case 10:
+	case 11:
+		div = 8;
+		break;
+	default:
+		div = 12;
+		break;
+	}
+	clk_rst_ctl.s.h_div = div;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+	/* Read it back, */
+	clk_rst_ctl.u64 = cvmx_read_csr(CVMX_UCTLX_CLK_RST_CTL(0));
+	clk_rst_ctl.s.h_clkdiv_en = 1;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+	/* 3d */
+	clk_rst_ctl.s.h_clkdiv_rst = 1;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+
+	/* 3e: delay 64 io clocks */
+	ndelay(io_clk_64_to_ns);
+
+	/*
+	 * Step 4: Program the power-on reset field in the UCTL
+	 * clock-reset-control register.
+	 */
+	clk_rst_ctl.s.p_por = 0;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+
+	/* Step 5:    Wait 1 ms for the PHY clock to start. */
+	mdelay(1);
+
+	/*
+	 * Step 6: Program the reset input from automatic test
+	 * equipment field in the UPHY CSR
+	 */
+	uphy_ctl_status.u64 = cvmx_read_csr(CVMX_UCTLX_UPHY_CTL_STATUS(0));
+	uphy_ctl_status.s.ate_reset = 1;
+	cvmx_write_csr(CVMX_UCTLX_UPHY_CTL_STATUS(0), uphy_ctl_status.u64);
+
+	/* Step 7: Wait for at least 10ns. */
+	ndelay(10);
+
+	/* Step 8: Clear the ATE_RESET field in the UPHY CSR. */
+	uphy_ctl_status.s.ate_reset = 0;
+	cvmx_write_csr(CVMX_UCTLX_UPHY_CTL_STATUS(0), uphy_ctl_status.u64);
+
+	/*
+	 * Step 9: Wait for at least 20ns for UPHY to output PHY clock
+	 * signals and OHCI_CLK48
+	 */
+	ndelay(20);
+
+	/* Step 10: Configure the OHCI_CLK48 and OHCI_CLK12 clocks. */
+	/* 10a */
+	clk_rst_ctl.s.o_clkdiv_rst = 1;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+
+	/* 10b */
+	clk_rst_ctl.s.o_clkdiv_en = 1;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+
+	/* 10c */
+	ndelay(io_clk_64_to_ns);
+
+	/*
+	 * Step 11: Program the PHY reset field:
+	 * UCTL0_CLK_RST_CTL[P_PRST] = 1
+	 */
+	clk_rst_ctl.s.p_prst = 1;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+
+	/* Step 12: Wait 1 uS. */
+	udelay(1);
+
+	/* Step 13: Program the HRESET_N field: UCTL0_CLK_RST_CTL[HRST] = 1 */
+	clk_rst_ctl.s.hrst = 1;
+	cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
+
+	/* Now we can set some other registers.  */
+
+	for (i = 0; i <= 1; i++) {
+		port_ctl_status.u64 =
+			cvmx_read_csr(CVMX_UCTLX_UPHY_PORTX_CTL_STATUS(i, 0));
+		/* Set txvreftune to 15 to obtain complient 'eye' diagram. */
+		port_ctl_status.s.txvreftune = 15;
+		cvmx_write_csr(CVMX_UCTLX_UPHY_PORTX_CTL_STATUS(i, 0),
+			       port_ctl_status.u64);
+	}
+}
+EXPORT_SYMBOL(octeon2_usb_clocks_start);
+
+void octeon2_usb_clocks_stop(void)
+{
+	union cvmx_uctlx_if_ena if_ena;
+
+	if (atomic_dec_return(&octeon2_usb_clock_start_cnt) != 0)
+		return;
+
+	if_ena.u64 = 0;
+	if_ena.s.en = 0;
+	cvmx_write_csr(CVMX_UCTLX_IF_ENA(0), if_ena.u64);
+}
+EXPORT_SYMBOL(octeon2_usb_clocks_stop);