From fa62e10d2613b9e9edbe944b890644b30e9d4ed7 Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Sat, 27 Aug 2016 14:01:19 +0200 Subject: [PATCH] clk: versatile/icst: support for AP baseboard clocks This adds support for the two ICST525-based clocks on the Integrator/AP baseboard, as documented in the board manual "Integrator/AP ASIC Development Motherboard", ARM DUI0098 B, pages 3-15 thru 3-18. Cc: Russell King Signed-off-by: Linus Walleij [sboyd@codeaurora.org: fixed uninitialized val warning] Signed-off-by: Stephen Boyd --- drivers/clk/versatile/clk-icst.c | 136 +++++++++++++++++++++++++++++++ 1 file changed, 136 insertions(+) diff --git a/drivers/clk/versatile/clk-icst.c b/drivers/clk/versatile/clk-icst.c index 8f06473b72ff..4faa94440779 100644 --- a/drivers/clk/versatile/clk-icst.c +++ b/drivers/clk/versatile/clk-icst.c @@ -29,15 +29,20 @@ #define VERSATILE_AUX_OSC_BITS 0x7FFFF #define INTEGRATOR_AP_CM_BITS 0xFF +#define INTEGRATOR_AP_SYS_BITS 0xFF #define INTEGRATOR_CP_CM_CORE_BITS 0x7FF #define INTEGRATOR_CP_CM_MEM_BITS 0x7FF000 +#define INTEGRATOR_AP_PCI_25_33_MHZ BIT(8) + /** * enum icst_control_type - the type of ICST control register */ enum icst_control_type { ICST_VERSATILE, /* The standard type, all control bits available */ ICST_INTEGRATOR_AP_CM, /* Only 8 bits of VDW available */ + ICST_INTEGRATOR_AP_SYS, /* Only 8 bits of VDW available */ + ICST_INTEGRATOR_AP_PCI, /* Odd bit pattern storage */ ICST_INTEGRATOR_CP_CM_CORE, /* Only 8 bits of VDW and 3 bits of OD */ ICST_INTEGRATOR_CP_CM_MEM, /* Only 8 bits of VDW and 3 bits of OD */ }; @@ -92,6 +97,38 @@ static int vco_get(struct clk_icst *icst, struct icst_vco *vco) return 0; } + /* + * The Integrator/AP system clock on the base board can only + * access the low eight bits of the v PLL divider. Bit 8 is tied low + * and always zero, r is hardwired to 46, and the output divider is + * hardwired to 3 (divide by 4) according to the document + * "Integrator AP ASIC Development Motherboard" ARM DUI 0098B, + * page 3-16. + */ + if (icst->ctype == ICST_INTEGRATOR_AP_SYS) { + vco->v = val & INTEGRATOR_AP_SYS_BITS; + vco->r = 46; + vco->s = 3; + return 0; + } + + /* + * The Integrator/AP PCI clock is using an odd pattern to create + * the child clock, basically a single bit called DIVX/Y is used + * to select between two different hardwired values: setting the + * bit to 0 yields v = 17, r = 22 and OD = 1, whereas setting the + * bit to 1 yields v = 14, r = 14 and OD = 1 giving the frequencies + * 33 or 25 MHz respectively. + */ + if (icst->ctype == ICST_INTEGRATOR_AP_PCI) { + bool divxy = !!(val & INTEGRATOR_AP_PCI_25_33_MHZ); + + vco->v = divxy ? 17 : 14; + vco->r = divxy ? 22 : 14; + vco->s = 1; + return 0; + } + /* * The Integrator/CP core clock can access the low eight bits * of the v PLL divider. Bit 8 is tied low and always zero, @@ -143,6 +180,16 @@ static int vco_set(struct clk_icst *icst, struct icst_vco vco) if (vco.r != 22) pr_err("ICST error: tried to use RDW != 22\n"); break; + case ICST_INTEGRATOR_AP_SYS: + mask = INTEGRATOR_AP_SYS_BITS; + val = vco.v & 0xFF; + if (vco.v & 0x100) + pr_err("ICST error: tried to set bit 8 of VDW\n"); + if (vco.s != 3) + pr_err("ICST error: tried to use VOD != 1\n"); + if (vco.r != 46) + pr_err("ICST error: tried to use RDW != 22\n"); + break; case ICST_INTEGRATOR_CP_CM_CORE: mask = INTEGRATOR_CP_CM_CORE_BITS; /* Uses 12 bits */ val = (vco.v & 0xFF) | vco.s << 8; @@ -225,6 +272,27 @@ static long icst_round_rate(struct clk_hw *hw, unsigned long rate, return DIV_ROUND_CLOSEST(rate, 500000) * 500000; } + if (icst->ctype == ICST_INTEGRATOR_AP_SYS) { + /* Divides between 3 and 50 MHz in steps of 0.25 MHz */ + if (rate <= 3000000) + return 3000000; + if (rate >= 50000000) + return 5000000; + /* Slam to closest 0.25 MHz */ + return DIV_ROUND_CLOSEST(rate, 250000) * 250000; + } + + if (icst->ctype == ICST_INTEGRATOR_AP_PCI) { + /* + * If we're below or less than halfway from 25 to 33 MHz + * select 25 MHz + */ + if (rate <= 25000000 || rate < 29000000) + return 25000000; + /* Else just return the default frequency */ + return 33000000; + } + vco = icst_hz_to_vco(icst->params, rate); return icst_hz(icst->params, vco); } @@ -235,6 +303,36 @@ static int icst_set_rate(struct clk_hw *hw, unsigned long rate, struct clk_icst *icst = to_icst(hw); struct icst_vco vco; + if (icst->ctype == ICST_INTEGRATOR_AP_PCI) { + /* This clock is especially primitive */ + unsigned int val; + int ret; + + if (rate == 25000000) { + val = 0; + } else if (rate == 33000000) { + val = INTEGRATOR_AP_PCI_25_33_MHZ; + } else { + pr_err("ICST: cannot set PCI frequency %lu\n", + rate); + return -EINVAL; + } + ret = regmap_write(icst->map, icst->lockreg_off, + VERSATILE_LOCK_VAL); + if (ret) + return ret; + ret = regmap_update_bits(icst->map, icst->vcoreg_off, + INTEGRATOR_AP_PCI_25_33_MHZ, + val); + if (ret) + return ret; + /* This locks the VCO again */ + ret = regmap_write(icst->map, icst->lockreg_off, 0); + if (ret) + return ret; + return 0; + } + if (parent_rate) icst->params->ref = parent_rate; vco = icst_hz_to_vco(icst->params, rate); @@ -368,6 +466,34 @@ static const struct icst_params icst525_apcp_cm_params = { .idx2s = icst525_idx2s, }; +static const struct icst_params icst525_ap_sys_params = { + .vco_max = ICST525_VCO_MAX_5V, + .vco_min = ICST525_VCO_MIN, + /* Minimum 3 MHz, VDW = 4 */ + .vd_min = 3, + /* Maximum 50 MHz, VDW = 192 */ + .vd_max = 50, + /* r is hardcoded to 46 and this is the actual divisor, +2 */ + .rd_min = 48, + .rd_max = 48, + .s2div = icst525_s2div, + .idx2s = icst525_idx2s, +}; + +static const struct icst_params icst525_ap_pci_params = { + .vco_max = ICST525_VCO_MAX_5V, + .vco_min = ICST525_VCO_MIN, + /* Minimum 25 MHz */ + .vd_min = 25, + /* Maximum 33 MHz */ + .vd_max = 33, + /* r is hardcoded to 14 or 22 and this is the actual divisors +2 */ + .rd_min = 16, + .rd_max = 24, + .s2div = icst525_s2div, + .idx2s = icst525_idx2s, +}; + static void __init of_syscon_icst_setup(struct device_node *np) { struct device_node *parent; @@ -408,6 +534,12 @@ static void __init of_syscon_icst_setup(struct device_node *np) } else if (of_device_is_compatible(np, "arm,syscon-icst525-integratorap-cm")) { icst_desc.params = &icst525_apcp_cm_params; ctype = ICST_INTEGRATOR_AP_CM; + } else if (of_device_is_compatible(np, "arm,syscon-icst525-integratorap-sys")) { + icst_desc.params = &icst525_ap_sys_params; + ctype = ICST_INTEGRATOR_AP_SYS; + } else if (of_device_is_compatible(np, "arm,syscon-icst525-integratorap-pci")) { + icst_desc.params = &icst525_ap_pci_params; + ctype = ICST_INTEGRATOR_AP_PCI; } else if (of_device_is_compatible(np, "arm,syscon-icst525-integratorcp-cm-core")) { icst_desc.params = &icst525_apcp_cm_params; ctype = ICST_INTEGRATOR_CP_CM_CORE; @@ -437,6 +569,10 @@ CLK_OF_DECLARE(arm_syscon_icst307_clk, "arm,syscon-icst307", of_syscon_icst_setup); CLK_OF_DECLARE(arm_syscon_integratorap_cm_clk, "arm,syscon-icst525-integratorap-cm", of_syscon_icst_setup); +CLK_OF_DECLARE(arm_syscon_integratorap_sys_clk, + "arm,syscon-icst525-integratorap-sys", of_syscon_icst_setup); +CLK_OF_DECLARE(arm_syscon_integratorap_pci_clk, + "arm,syscon-icst525-integratorap-pci", of_syscon_icst_setup); CLK_OF_DECLARE(arm_syscon_integratorcp_cm_core_clk, "arm,syscon-icst525-integratorcp-cm-core", of_syscon_icst_setup); CLK_OF_DECLARE(arm_syscon_integratorcp_cm_mem_clk, -- 2.30.2