diff options
Diffstat (limited to 'drivers/usb/host/octeon2-common.c')
| -rw-r--r-- | drivers/usb/host/octeon2-common.c | 185 |
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); |