[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH v5 6/7] xen/arm: zynqmp: implement zynqmp_eemi
Hi Stefano, On 03/12/2018 21:03, Stefano Stabellini wrote: From: "Edgar E. Iglesias" <edgar.iglesias@xxxxxxxxxx> From: Edgar E. Iglesias <edgar.iglesias@xxxxxxxxxx> zynqmp_eemi uses the defined functions and structs to decide whether to make a call to the firmware, or to simply return a predefined value. Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xxxxxxxxxx> Signed-off-by: Stefano Stabellini <stefanos@xxxxxxxxxx> --- Changes in v5: - remove mmio_access handling Changes in v4: - add #include as needed - improve comment - code style --- xen/arch/arm/platforms/xilinx-zynqmp-eemi.c | 181 +++++++++++++++++++--------- 1 file changed, 125 insertions(+), 56 deletions(-) diff --git a/xen/arch/arm/platforms/xilinx-zynqmp-eemi.c b/xen/arch/arm/platforms/xilinx-zynqmp-eemi.c index 92a02df..9ecf286 100644 --- a/xen/arch/arm/platforms/xilinx-zynqmp-eemi.c +++ b/xen/arch/arm/platforms/xilinx-zynqmp-eemi.c @@ -76,10 +76,10 @@#include <xen/iocap.h>#include <xen/sched.h> +#include <asm/smccc.h> #include <asm/regs.h> #include <asm/platforms/xilinx-zynqmp-eemi.h>-#if 0struct pm_access { mfn_t mfn; @@ -309,67 +309,136 @@ static bool domain_has_reset_access(struct domain *d, uint32_t rst) return pm_check_access(pm_reset_access, d, rst); }-/*- * Check if a given domain has access to perform an indirect - * MMIO access. - * - * If the provided mask is invalid, it will be fixed up. - */ -static bool domain_has_mmio_access(struct domain *d, - bool write, paddr_t addr, - uint32_t *mask) Why do you remove code that you just introduced? +bool zynqmp_eemi(struct cpu_user_regs *regs) { - unsigned int i; - bool ret = false; - uint32_t prot_mask = 0; - - /* - * The hardware domain gets read access to everything. - * Lower layers will do further filtering. - */ - if ( !write && is_hardware_domain(d) ) - return true; + struct arm_smccc_res res; + uint32_t fid = get_user_reg(regs, 0); + uint32_t nodeid = get_user_reg(regs, 1); You didn't address my concern regarding SMC32 vs SMC64 convention. As I said earlier on, at least CALL_COUNT, UID and VERSION are only accessible using the SMC32 convention. I can't tell for the other as the EEMI spec does not seem to specify it. I would be surprised that EEMI would ignore tops bits of the ID given they convey different information (e.g fast/yielding call, 32/64-bit convention). Looking at the branch you mentioned earlier on, zynqmp_pm_invoke_fn (drivers/firmware/xilinx/zynqmp.c) is definitely using the SMC64 calling convention as described in the documentation above the function. So this needs to be fixed properly. + unsigned int pm_fn = fid & 0xFFFF; + enum pm_ret_status ret;- /* Scan the ACL. */- for ( i = 0; i < ARRAY_SIZE(pm_mmio_access); i++ ) + switch ( pm_fn ) { - ASSERT(pm_mmio_access[i].start + pm_mmio_access[i].size >= - pm_mmio_access[i].start); - - if ( addr < pm_mmio_access[i].start ) - return false; - if ( addr >= pm_mmio_access[i].start + pm_mmio_access[i].size ) - continue; - - if ( write && pm_mmio_access[i].readonly ) - return false; - if ( pm_mmio_access[i].hwdom_access && !is_hardware_domain(d) ) - return false; - if ( !domain_has_node_access(d, pm_mmio_access[i].node) ) - return false; - - /* We've got access to this reg (or parts of it). */ - ret = true; - - /* Permit write access to selected bits. */ - prot_mask |= pm_mmio_access[i].mask ?: GENMASK(31, 0); - break; - } - /* - * Masking only applies to writes: values are safe to read, but not - * all bits are writeable. + * We can't allow CPUs to suspend without Xen knowing about it. + * We accept but ignore the request and wait for the guest to issue + * a WFI or PSCI call which Xen will trap and act accordingly upon. */ - if ( write ) - *mask &= prot_mask; - - return ret; -} -#endif + case PM_SELF_SUSPEND: + ret = XST_PM_SUCCESS; + goto done; + + case PM_GET_NODE_STATUS: + /* API for PUs. */ + case PM_REQ_SUSPEND: + case PM_FORCE_POWERDOWN: + case PM_ABORT_SUSPEND: + case PM_REQ_WAKEUP: + case PM_SET_WAKEUP_SOURCE: + /* API for slaves. */ + case PM_REQ_NODE: + case PM_RELEASE_NODE: + case PM_SET_REQUIREMENT: + case PM_SET_MAX_LATENCY: + if ( !domain_has_node_access(current->domain, nodeid) ) + { + gprintk(XENLOG_WARNING, + "zynqmp-pm: fn=%u No access to node %u\n", pm_fn, nodeid); + ret = XST_PM_NO_ACCESS; + goto done; + } + goto forward_to_fw; + + case PM_RESET_ASSERT: + case PM_RESET_GET_STATUS: + if ( !domain_has_reset_access(current->domain, nodeid) ) + { + gprintk(XENLOG_WARNING, + "zynqmp-pm: fn=%u No access to reset %u\n", pm_fn, nodeid); + ret = XST_PM_NO_ACCESS; + goto done; + } + goto forward_to_fw; + + /* These calls are safe and always allowed. */ + case ZYNQMP_SIP_SVC_CALL_COUNT: + case ZYNQMP_SIP_SVC_UID: + case ZYNQMP_SIP_SVC_VERSION: + case PM_GET_TRUSTZONE_VERSION: + case PM_GET_API_VERSION: + case PM_GET_CHIPID: + goto forward_to_fw; + + /* No MMIO access is allowed from non-secure domains */ + case PM_MMIO_WRITE: + case PM_MMIO_READ: + gprintk(XENLOG_WARNING, + "zynqmp-pm: fn=%u No MMIO access to %u\n", pm_fn, nodeid); + ret = XST_PM_NO_ACCESS; + goto done; + + /* Exclusive to the hardware domain. */ + case PM_INIT: + case PM_SET_CONFIGURATION: + case PM_FPGA_LOAD: + case PM_FPGA_GET_STATUS: + case PM_SECURE_SHA: + case PM_SECURE_RSA: + case PM_PINCTRL_SET_FUNCTION: + case PM_PINCTRL_REQUEST: + case PM_PINCTRL_RELEASE: + case PM_PINCTRL_GET_FUNCTION: + case PM_PINCTRL_CONFIG_PARAM_GET: + case PM_PINCTRL_CONFIG_PARAM_SET: + case PM_IOCTL: + case PM_QUERY_DATA: + case PM_CLOCK_ENABLE: + case PM_CLOCK_DISABLE: + case PM_CLOCK_GETSTATE: + case PM_CLOCK_GETDIVIDER: + case PM_CLOCK_SETDIVIDER: + case PM_CLOCK_SETRATE: + case PM_CLOCK_GETRATE: + case PM_CLOCK_SETPARENT: + case PM_CLOCK_GETPARENT: + if ( !is_hardware_domain(current->domain) ) + { + gprintk(XENLOG_WARNING, "eemi: fn=%u No access", pm_fn); + ret = XST_PM_NO_ACCESS; + goto done; + } + goto forward_to_fw; + + /* These calls are never allowed. */ + case PM_SYSTEM_SHUTDOWN: + ret = XST_PM_NO_ACCESS; + goto done; + + default: + gprintk(XENLOG_WARNING, "zynqmp-pm: Unhandled PM Call: %u\n", fid); + return false; + }-bool zynqmp_eemi(struct cpu_user_regs *regs)-{ - return false; +forward_to_fw: + arm_smccc_1_1_smc(get_user_reg(regs, 0), + get_user_reg(regs, 1), + get_user_reg(regs, 2),value to + get_user_reg(regs, 3), + get_user_reg(regs, 4), + get_user_reg(regs, 5), + get_user_reg(regs, 6), + get_user_reg(regs, 7), + &res); If you use always SMCCC 1.1, then you should add code to deny Xen boot on platform not supporting SMCCC 1.1 or later. Furthermore, you are forwarding unsanitized values to the firmware. For instance, what would happen if the number of parameters of the call are increased? How are you sure this will not open a hole? + + set_user_reg(regs, 0, res.a0); + set_user_reg(regs, 1, res.a1); + set_user_reg(regs, 2, res.a2); + set_user_reg(regs, 3, res.a3); + return true; + +done: + set_user_reg(regs, 0, ret); + return true; }/* Cheers, -- Julien Grall _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxxx https://lists.xenproject.org/mailman/listinfo/xen-devel
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